Bulletin 4473 : Good food guide for sheep Good...Bulletin 4473 ISSN 1326-415X Feeding Sheep for Meat Production in the Agricultural Areas of Western Australia The Good Food Guide forSHEEP

Bulletin 4473

ISSN 1326-415X

Feeding Sheep for MeatProduction in the AgriculturalAreas of Western Australia

The Good Food Guide forSHEEP

Prepared by the Meat Program,Department of Agriculture.September 2001.

Bulletin 4473

ISSN 1326-415X

Feeding Sheep for MeatProduction in the AgriculturalAreas of Western AustraliaEdited by Dr Keith Croker and Peter Watt,Department of Agriculture, South Perth.

Prepared by the Meat and Dairy Program,Department of Agriculture.September 2001.

© Chief Executive Officer of the Department of Agriculture 2001.This material may be reprinted provided that the article and the author(s)are acknowledged. Edited and published by Information Services, Departmentof Agriculture, Locked Bag No. 4, Bentley Delivery Centre,WA 6983.

The Good Food Guide forSHEEP

T h e G o o d Fo o d G u i d e fo r S H E E PCO

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Introduction

Sheep meat enterprises in Western Australia – Eliza Dowling and Sarah Wiese 7

Principles of ruminant nutrition – John Milton, Janet Paterson and Daniel Roberts 13

Pasture

ó Grazing annual pastures – Keith Devenish and Mike Hyder 20

ó Pastures in the Agricultural Area – Trevor Lacey, Keith Devenish and Clinton Revell 25

ó Sandplain lupins. A good feed for lambs – Keith Croker, Stewart Gittins,

Grant Doncon and Jeremy Allen 27

ó Grazing saltland pastures – Trevor Lacey 29

ó Dryland lucerne grazing systems – Trevor Lacey and Keith Devenish 32

ó Tagasaste (fodder shrub) – Tim Wiley 37

ó Native perennial grasses in permanent pastures – Roy Butler 40

ó Subtropical perennial grasses – Tim Wiley 43

ó Summer fodder crops – Tim Wiley 47

Crops

ó Sheep performances on cereal and canola stubbles – Daniel Roberts and

Janet Paterson 52

ó Grazing sheep on grain legume stubbles – Keith Devenish 56

ó Grazing sheep on matured grain legume crops – Keith Devenish 61

ó Increasing lamb growth on medic pasture cover cropped with sweet lupins –

Keith Devenish, Gary Hepworth and Natalie Coonan 63

Fodder – Roy Butler and John Milton 65

Supplementary feeding of sheep for meat production – John Milton and Janet Paterson 73

Lot-feeding prime lambs – John Milton 79

Feeding for meat colour – Robin Jacob and Graham Gardner 85

Sheep health issues – Don Moir 89

Sources of information on related subjects 95

Web sites of interest 97

Glossary 99

Index 101

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Since the late 1980s, when wool prices began to decline, Western Australian farmers have steadilyreduced their flocks. The Western Australian flock now contains approximately 25 million sheep,down 13 million-head from its highest point in 1990. As sheep numbers have fallen, interest in theproduction of sheep meat (lamb, hogget and mutton) has grown.

Many farmers have turned to first cross lamb production, joining meat breed rams to Merino ewes.In 2000/2001, approximately 59 per cent of the 5.1 million lambs expected to be turned off inWestern Australia will be first cross lambs. Merino lambs will constitute approximately 40 per centof the turn off and barely one per cent will be second cross lambs.

Most cross bred lambs in Western Australia are sired by British breed rams, such as Suffolks, PollDorsets and Border Leicesters, but the choice of breeds has widened in recent years. Some of the‘new’ breeds have been developed in Australia, but most have been imported. Dorpers and WhiteDorpers, Damaras, Karakuls, Africaners, South African Meat Merinos and Dohne Merinos havebeen imported from South Africa. Texels, Finnsheep and East Friesians have come from Europe(via New Zealand) and American Suffolks have come from the United States.

Farmers with pure Merino flocks are placing more emphasis on the meat value of their sheep.The growing success of the Prime Merino Lamb Alliance, which now has more than 300 producermembers, shows both the versatility of Merino sheep and the willingness of woolgrowers to learnnew skills in sheep meat production.

Breeding is undoubtedly important in sheep meat production, particularly in combination with asystem such as LAMBPLAN®, which uses objective measurements to determine true genetic value.However, even well bred, genetically superior sheep cannot perform satisfactorily unless they areproperly fed.

The Good Food Guide for Sheep has been produced to provide Western Australian farmers with aconcise compilation of current information on feeding sheep for meat production. Although thereare already numerous publications about sheep nutrition, many of them relate to wool production,reproduction or drought feeding, or they concentrate on particular feeds or feeding systems.

This book contains information on a wide range of feeds and feeding methods. Just as there is nosingle ‘best’ sheep breed for meat production, there is no ultimate feed regime for sheep for growth.

I hope you will find The Good Food Guide for Sheep an interesting and useful reference.

Graeme RobertsonChief Executive OfficerDepartment of AgricultureSeptember 2001

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The major cost associated with the production of sheep meat is that of feeding.Efficient production therefore requires a careful choice of the most appropriate feedingsystem. The diverse range of climatic conditions and production systems available inWestern Australia means that there are many feeding strategies suitable for raising orfinishing sheep for meat production. This publication aims to provide farmers withagronomic and production information on these various feeding options.

A substantial proportion of levy and State Government funds is now directedtowards producer driven on-farm testing. While these on-farm demonstrations providean excellent learning experience for the farmers involved, the information does notalways reach the wider audience.

At the same time, because there are limited resources available for comprehensiveresearch, these small farm-scale demonstrations are often the only source of informationon different production systems available to farmers. One of the reasons this book wasproduced was to capture some of these case studies and to share the informationprovided by them.

Farmers, as well as new workers in the sheep meat industry, are probably unaware ofmuch of the information available from past work done in Western Australia on sheepfeeding systems. Over many years, staff of Department of Agriculture have been involved incollecting information on the performances of sheep grown using a range of feeds.

This book provides a substantial collation of this information from many publica-tions, and from unpublished records, research results and observations as well as thememories and notes of some producers and agency staff. Until now little of this work,past and present, has been brought together in a readily accessible form that is focusedon sheep meat production.

‘The Good Food Guide for Sheep’ provides farmers with a single, concise, well-referenced and informative publication on all aspects of feeding sheep for meatproduction. It is hoped this will assist farmers in making well-informed choices of themost efficient production systems for their sheep meat enterprise.

Many people from various sections of Department of Agriculture contributed to thebulletin through criticisms and comments on the articles. There are too many toacknowledge individually, but the assistance freely given by all officers approachedimproved the quality of the articles. The production of the bulletin was funded by theMeat Program of Department of Agriculture.

Dr Sarah WieseFormer Project ManagerSheep Meat Research and Demonstration

S h e e p M e a t E n t e r p r i s e s i nW E ST E R N AUSTR ALIAEliza Dowling and Sarah Wiese,

Department of Agriculture, Narrogin


S h e e p M e a t E n t e r p r i s e s i n W E ST E R N AU ST R A L I A

Introduction Western Australia's small

population and closeness toexport markets for sheep meat,have a strong influence on themarketing of sheep meatproducts and on the enterprisesrequired to produce them.Presently one-third of all sheepsold for meat is exported live,one-third is exported as carcaseand piece meats and theremaining third is used tosupply the domestic market forsheep meat products.

The lamb marketThe largest sheep meat

enterprise in Western Australiais for lamb, with about twomillion lambs slaughtered eachyear. A further one millionlambs are exported live. Thenumber of lambs exportedboth live and as carcases hasincreased over recent yearswhile the domestic market hasbeen relatively static.

The number of lambsproduced by the different enter-prises is influenced greatlyby changes in the markets.Producers can follow a rangeof options for marketingtheir lambs. These are describedbelow.

Paddock sales

Lambs are inspected on thevendor’s property by a buyerand are then sold straight outof the paddock. The price isusually based on dollars perhead. Twenty-five per cent oflambs slaughtered in WesternAustralia are traded bypaddock sales.

Saleyard auction

A further 25 per cent oflambs slaughtered in WesternAustralia are sold through thesaleyard auction system wheremultiple buyers bid for pens ofsheep on a dollar per head basis.

Over the hook

Lambs are delivereddirectly to the abattoir andmay be sold with or without anagent. Change of ownershiptakes place at the abattoir.There is a flat rate on a dollarsper kilogram basis, or a priceschedule depending on thespecifications of the individuallambs. Preferred specificationsare generally fat score 2 or 3

(6 to 15 millimetres of fat overthe ribs) and greater than18 kilograms carcase weight.Domestic markets tend to alsohave a preferred upper limitfor carcase weight of around23 kilograms. Forty-five percent of lambs slaughtered inWestern Australia are traded‘over the hook’.

Computer Assisted LivestockMarketing (CALM)

Here the sale is on-farm,with details entered into acomputer. Lambs are assessedbefore sale by an accreditedCALM assessor who describesthe lambs to the buyers via thedescriptions that are enteredinto the computer. Producers donot need to own or be able tooperate a computer to sell whenusing the CALM system. Onlyfive per cent of lambs slaugh-tered in Western Australia aretraded by CALM. Several of the

stock firms have licensed CALMassessors and can provide moreinformation on CALM.

The different costs assoc-iated with each marketingmethod include the agent'scommission, yard fees, transport,insurance, transaction leviesand assessment fees.

Meeting healthrequirements

Regardless of the marketingmethod used, good animalhusbandry is required to meethealth specifications. Sheepthat are affected by arthritis,cheesy gland, dermatitis,hydatids or which have grassseeds, will either incur a heavypenalty at slaughter or will notbe accepted. There has been awidely successful campaign inWestern Australia to ensurethat all sheep for the live exportmarket are vaccinated againstscabby mouth. (For furtherinformation on animal healthmatters, please refer to thechapter ‘Sheep Health Issues’).

Prime lambsSucker lambs

Sucker lambs are lambsthat have not been weanedfrom their mothers before sale.Usually they need to maintaina growth rate above 250 gramsper head per day to reach theirminimum target slaughterweight of 40 kilograms before thegreen feed dries off (Figure 1).Sucker lambs are a low inputenterprise and, with the gener-ally high volume of lambs beingsold in spring, tend to returnlower prices. Early sucker lambs,



(June, July, and August), attractpremium prices (see Figure 2

above). However, producersneed to plan for a lambing inmid April to achieve a premiumin this market. With earlierlambing, ewes will require morefeed in autumn.

Carryover lambs (weaned lambs)

Carryover lambs are thosethat are weaned from theirmothers and grown out to meetvarious market requirements.They are usually sold outsidethe spring flush of lambs.With carryover lambs, theaim is to produce a finishedlamb out of season (fromDecember to August) that willgenerate a price premium (seeFigure 3 for average prices forcarryover lambs).

The minimum liveweight atslaughter for these lambs shouldbe 40 kilograms, and the lambsgoing into summer should be atleast 30 kilograms. With a laterlambing (July/August) whengreen feed is available, there islittle extra cost for the ewe, butthere is for finishing the lambs insummer or autumn when greenfeed is no longer available. Thisvaries depending on whether ahigh or low input system is used.

Low input system: With alow input system, lambs areusually finished with grain(lupin, oats, barley or wheat) fedthrough self-feeders, or trailedout while grazing on stubbles oflupin, cereal or canola. This is alow-cost option but has itsdisadvantages particularly whensummer rain reduces the nutri-tional value of the dry feed orstubble causing lambs to losecondition. The line of lambsproduced is usually of variablecondition with some falling out-side specifications, and therebyincurring penalties.

PRICEC/KGDRESSEDWEIGHT

0

50

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150

200

250

Jul Aug Sep Oct Nov Dec

Figure 2. Cents/kilogram for dressed weights of 13 to 16.5 kilogram carcase(Condition score 2). Six-year averages to 1999 for months July to December.

Border Leicester x Merino carryover lambsready for slaughter at Beverley.

Poll Dorset x Merino sucker lambs finishedon annual spring pasture in Pingelly.

AGE IN DAYS

0

10

20

30

40

50

60

0 30 60 90 120 150 180 210

LIVEWEIGHTIN KG

Figure 1. Expected liveweight gain of crossbred sucker lambs born in April/May.

High input system: With ahigh input system, carryoverlambs are intensively fed infeedlots to meet weight andgrade specifications. This optionis expensive and time consum-ing but with good managementproduces a consistent productthat should earn a pricepremium. The extra costs oflot-feeding lambs include shear-ing, vaccinating and drenchinglambs into the feedlot.(For more information seethe chapter on lot-feeding ofprime lambs).

Merino lambs

Traditionally a by-productof the wool industry, Merinolambs grow up to 100 gramsslower per day than crossbredlambs and their skins are oflower value. However, Merinostend to be leaner and can makeheavier weights than crossbredswithout becoming over fat. Theyrequire more feed to be finishedproperly and are slower to adaptand perform in a feedlot. Theliveweights and growth rates ofautumn and spring born Merino

lambs in the eastern wheatbeltare provided as an example ofthe growth performance thatcan be expected from Merinolambs (see Figures 4 and 5).

Whilst domestic demandfor pure Merino lamb meat is

extremely low, Merino lambsmake up a large part of theexport market. There is a strongdemand for Merino lamb car-cases in the Middle East market.Historically, the WesternAustralian Meat MarketingCooperative (WAMMCO) con-trolled the export market forMerino lambs, but this changedon 1 January 2000 whenWAMMCO lost its status asWestern Australia’s soleexporter of lamb. With limitedselling options for Merino lambsit is worthwhile for producers tosecure a contract before startingto lot-feed lambs.

T H E G O O D F O O D G U I D E F O R S H E E P1 0



0

50

100

150

200

250

Jan Feb Mar Apr May Jun Jul Aug

Figure 3. Six-year averages to 1999 for months January to August. Cents/kilogram fordressed weights of 13 to 16.5 kilogram (Condition score 2).

LIVEWEIGHT(KG)

March/April bornJuly/August born

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Aug Oct Dec Feb Apr Jun Aug Oct

AVERAGEDAILYWEIGHTGAIN(G/HEAD/DAY)

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Jan Mar Apr Jun Jul Aug Oct DecFeb May Nov

Figure 4. The average weights of spring (July/Aug) and autumn (March/April) born Merinoweaners in the eastern wheatbelt.

Figure 5. The average rate of weight gain throughout the year for Merino weaners in theeastern wheatbelt.



The Live Export MarketThe value of live sheep expo-

rted from Western Australia forthe financial year 1999/2000

was 150 million dollars(ABS figures). This represents anexport in that year of 3.85

million sheep. The preferred livesheep for Middle EasternMuslims is a young unblem-ished (entire) ram, with nophysical deformities or disease.Previously Western Australiahas exported older Merinowethers, but the percentage ofyounger sheep has steadilyincreased in the past eight years(see Figure 6).

Live export of lambs

The minimum requirementis a healthy lamb at 35 kilogramsliveweight. Buyers usually take alarge line of lambs that are lessuniform than would be accept-able to the domestic market.Thepreference is for unblemishedram lambs over wethers. Thereare very few opportunities forexport of ewe lambs.

Lambs vaccinated forscabby mouth and shorn beforeshipping are preferred. Somesupplementary feeding may berequired to bring lambs up to asuitable weight and conditionfor shipping.There are few othercosts in producing lambs for liveexport. Good opportunities existfor contract production of fattailed breeds.

Ram lambs for live export

Both Merino and crossbredlambs are acceptable for theram lamb market. However,because of faster growth rates,crossbreds can reach weightspecifications more easily. Ramlambs need fewer procedures atmarking since mulesing, cas-trating and often ear taggingare not required. Lambs should

be weaned and separated fromfemales at 12 to 14 weeks of ageas they become sexually activeat about this age. Ram lambshave the potential to grow20 per cent faster than wethersbut they also have a higherenergy requirement. They canalso be difficult to finish if thefeed supply becomes low.

Fat tailed breeds for live export

Fat tail breeds command apremium price in the MiddleEast as buyers in these marketsprefer breeds with fat tails.Contracts are available at mat-ing, giving a guaranteed priceper head for lambs that meetthe required specifications forliveweight and condition score.Fat tail ewe lambs are alsobecoming acceptable to thelive export market. Fat tailbreeds are acceptable in theexport carcase market shouldthey not make the contractspecifications for live ship-ping, or in some cases can besold as store lambs to be finishedin a feedlot.

Fat tail crossbred lambsexhibit the same hybrid vigouras other crossbred lambs.

Live export wethers

Adult wethers vaccinatedfor scabby mouth and shornbefore shipping are preferred.Preference is for a big-framedsheep in condition score 2 to 3.Older wethers were supplied inearlier years, but more recentdemand has been met withyounger mature wethers (two tothree years old). The demand formature wethers predominates,but export of hoggets and lambs

Damara x Merino fat tail lambs for liveexport at Narembeen.

0

20

40

60

80

100

Years

(%)

Adult (%)Lambs & hoggets (%)

91 92 93 94 95 96 97 98

Figure 6. The proportion of adult versus young live sheep exported from 1991 to 1998.

is increasing, with occasionalopportunities for ewes. Lowwool prices have resulted infewer wethers available forexport, as producers turn moreto cropping enterprises.

MuttonThere is a market for old

ewes and rams that are culledfor age, are of poor fertility, orare surplus to requirements.Mutton produced should be85 per cent lean. Merinos ofcondition score 2 readily meetthis requirement. Boned car-cases are cored to test forfat content. As most of theWestern Australian sheep thatare culled for age are Merinos,meeting the criterion for85 per cent lean meat is notusually a problem.

As with all other sheepenterprises, penalties are incu-rred at slaughter for diseasesand other health issues. Cheesygland is more of a problem inolder animals. This is becausethe disease is spread at shear-ing by sheep carrying thedisease coughing onto sheepwith open cuts,and so the preva-lence of the disease in a flockgradually increases with the ageof the flock.

Mutton prices often showseasonal fluctuation and havebeen very low in recent times,despite the fall in sheepnumbers in Western Australianflocks (see Figure 7). Sheep forthe mutton market can besold through saleyard auctions,direct paddock sales andrecently through WAMMCO.

Further ReadingAMLC. Production andMarketing of Large Lean Lambs.

Bulletin No. 4645. Controllingsheep meat disorders.

Farmnote 72/2000. Sheephealth in a feedlot.

Farmnote 74/2000. Achievingproduction targets forprime lambs.

Farmnote 76/2000. Lot-feedingprime lambs.

Farmnote 25/99. Preparationand assessment of sheep andlambs for slaughter.

Farmnote 68/94. The Awassifat-tail sheep

Farmnote 96/94. Pre-roadtransport handling and care oflive sheep for export




0

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Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Figure 7. Cents/kilogram for dressed weights of 19 to 26 kilogram (Condition score 3).Six-year averages to 1999 for months January to December.

P r i n c i p l e s o f Ru m i n a n tN U T R I T I O NJohn Milton, Department of Agriculture, based at

The University of Western Australia, Nedlands;Janet Paterson, Sci Scribe Scientific Copywriting, Brookton

and Daniel Roberts, Department of Agriculture, Katanning.


P r i n c i p l e s o f Ru m i n a n t N UT R I T I O N

Definition of animalproduction

Animal production is con-cerned with the conversion ofchemical components in foragesand grains into meat, wool andmilk. The nitrogen, carbon, andminerals in pasture and otherfeeds are converted to muscle,milk and wool through theprocesses of digestion, absorp-tion and assimilation within thebody of an animal. How effi-ciently this occurs depends onthe quality and quantity of thefeed available as well as the typeof animal eating the feed.

Uniqueness of ruminantanimals

Sheep are ruminants and assuch are characterised by havinga specialised stomach with anumber of compartments, oneof which is known as the rumenor paunch. The rumen is basi-cally a 4 to 10-litre vat in whichmillions of microbes fermentincoming feed into products thatthe sheep then uses to grow.

Without these microbessheep could not exist becausethe microbes possess the specialability to break down theotherwise indigestible cellulosecomponent of plant material.Cellulose forms a large part ofthe fibrous feed of ruminants.

No animal has the enzymescapable of breaking apart thecellulose bonds to release theenergy they contain. Thus,without the microbes, thesheep could not access theenergy contained within fibrousplant feeds.

Another special feature ofruminants is their ability to‘chew the cud’ or ruminate. Asa normal part of eating, food isregurgitated from the rumeninto the mouth and re-chewed.This makes the feed particlessmaller and increases theirsurface area so that when theyre-enter the rumen it is easierfor the microbes to access thefeed and continue their fermen-tation. Without this process ofrumination, the feed particleswould remain too large forthe microbes to access thecarbohydrates and proteincontained within them.

The microbes in the rumenferment feed carbohydrates toproduce volatile fatty acids.Thesevolatile fatty acids are the majorsource of energy for the sheep.

Carbohydrates such assoluble sugars and starch areeasily broken down by themicrobes. Others, such as thecelluloses contained within thecell walls of plant material aremore complicated in structureand take longer to break down.

Another complex materialknown as lignin can not bebroken down at all by the rumenmicrobes and its presence inmature plant material cons-iderably limits the efficiency offibre digestion by the rumenmicrobes.

Plant protein is brokendown into its component aminoacids by the rumen microbes.These are either incorporatedinto microbial protein ordegraded further to produceammonia that is then used tosynthesise microbial protein or isabsorbed into the blood streamto be recycled or excreted as ureain the sheep’s urine. When themicrobes themselves pass fromthe rumen, through the acidstomach and into the smallintestine, they are then digestedinto amino acids and these areabsorbed into the sheep’s bloodstream. Microbial protein canbe of high quality in that itgenerally contains the rightbalance of the amino acidsneeded by the sheep to synthesisemuscle, wool and milk protein.

Nutritional requirementsof the ruminant

When we consider thenutritional requirements of theruminant we must also considerthe nutritional needs of themicrobial population in the

K E Y M E S S AG E Só Energy and protein are the key nutrients that limit sheep production.ó Deficiencies of vitamins and minerals can be of particular importance in lambs.ó To feed sheep successfully, we must aim to meet the nutrient needs of the

microbial population in the rumen of the sheep.


P r i n c i p l e s o f Ru m i n a n t N U T R I T I O N

rumen. In essence we aim to‘feed the rumen microbes tofeed the sheep.’ If we are ableto maintain a healthy, produc-tive microbial population thenwe can be confident that thesheep will receive adequateenergy (in the form of volatilefatty acids) and protein (in theform of microbial protein).

EnergyEnergy provides the power

needed to drive all the meta-bolic processes of an animal.Without it, chemical reactionswould not occur and muscle,milk and wool could not besynthesised. Provided there isadequate protein in the diet,the amount of energy avail-able to an animal determineshow productive the animal canbe in terms of meat, wool andmilk production.

The key factor in supplyingenergy for sheep production ishow easily the energy can beextracted from a feed. In otherwords how quickly the sheep’sdigestive processes can accessand use this energy to producemeat, wool or milk.

The speed with which theenergy becomes availabledepends on how digestible thefeed is. Feeds such as greenpasture, good hay or grains areeasily digested because theycontain large amounts of solu-ble sugars and starches andonly a small proportion of theless digestible structural car-bohydrates such as celluloseand lignin found in cell walls.

As plants age, more andmore of these structural carbo-hydrates are laid down in the

stems and the soluble, moresimple sugars stored in thestems are moved to form theseed heads or grain. Thismeans that feeds such as drypasture or straw take longer todigest because they containless soluble sugars and thechemical bonds that bind thecell walls together are verystrong and require more timeand energy to break than thebonds that hold simple sugarstogether.

When pastures begin to‘hay off’ or sheep are put ontostubbles, their food intake gener-ally drops off. This is because ittakes longer for the microbes tobreak down the structural carbo-hydrates contained in these feedsand, in consequence, the feedremains in the rumen for longer.The sheep can not eat more feeduntil the rumen empties.

The total energy content ofa feed is known as its ‘grossenergy’ and is a measure of theamount of heat generated whenthe feed is completely com-busted to ash in the presence ofoxygen. However not all theenergy in a feed is available toan animal since some remainstrapped in the plant cells and isunable to be extracted by theanimal’s digestive processes.Additional energy is lost in thegaseous products of digestionsuch as CO2 and methane and asmall amount of energy is alsolost in the urine of the animal.Once these losses of energy aretaken into account, the remain-ing feed energy is known as the‘metabolisable energy’ which is

the energy available to the ani-mal for the metabolic processesof maintenance and growth.

It is the metabolisableenergy content of a feed thatdetermines how much produc-tion can be achieved by ananimal, that is, whether ananimal’s weight will be main-tained, increased or decreased.It is essential to know themetabolisable energy content offeeds when formulating dietsand developing feed budgets forruminants.

Since metabolisable energyis difficult to measure, it isusually calculated from thedigestible dry matter of the feedusing an appropriate equation.The greatest loss of energy whenforage is digested is that lost inthe animal’s faeces. Put simply,digestible dry matter is theproportion of the dry matterconsumed that is not excreted inthe faeces. Digestible dry matteris expressed as a percentage,that is, the proportion of drymatter in the feed that can bedigested by the animal.

A young ryegrass/cloverpasture can have a digestible drymatter value as high as 80 percent and a calculated metabolis-able energy of 11.8 megajoulesper kilogram of dry matter.This issimilar to a reasonable qualitybarley grain.This means that theanimal can digest 80 per centof the dry matter in the dietand that for every kilogram offeed eaten, 11.8 megajoules ofmetabolisable energy will bereleased to the animal.

A mature grass-dominanttropical pasture that hasrecently finished flowering and

is starting to become lignified,may have a digestible dry mat-ter value of about 60 per centwith an metabolisable energy of8.6 megajoules per kilogram ofdry matter. On the other hand, awheat stubble that has littleleaf material present, is heavilylignified and contains a signifi-cant amount of indigestiblesilica, may have a digestible drymatter value of only 40 per centwith a metabolisable energy of5.6 megajoules per kilogram ofdry matter.

Short seasons such as thatexperienced in 2000 producepastures and stubbles of arelatively high digestible drymatter. When the season stopsabruptly, the plants do not havetime to lay down structural car-bohydrates and there is lessmovement of soluble sugars outof the stem and into the seedheads. The nutritive value ofthis dry feed will remain highthroughout the summer as longas there is no summer rain toleach out the soluble sugars inthe stems. Long seasons givestubbles of poorer qualitybecause of the high proportionof structural carbohydrates andlow amounts of soluble sugarsremaining in the dry forage.

Animals require energy tomaintain their basic metabolicprocesses such as kidney, liver,brain and heart function as wellas to lay down muscle, fat,protein and wool. The energyrequired to maintain processessuch as heart function is term-ed the ‘maintenance energyrequirement’ of the animal. The

amount of energy needed tomaintain an animal depends onwhat the animal is doing andwhat environment it is living in.For instance, sheep produced inhilly country will need extraenergy for maintenance to walkup hills in search of food.Similarly, sheep grazing a sparsepasture will have to walk fur-ther and therefore require moremaintenance energy than asheep grazing a relatively dense,green pasture or one that ishoused and lot fed.

A 50 kilogram sheep walk-ing three kilometres to waterand back again each day willincrease its maintenance requ-irement by 0.78 megajoules or14 per cent. If it climbed a totalof 600 metres on the way itsmaintenance requirement willincrease by an additional 0.42

megajoules making a totalincrease of 1.2 megajoules or21 per cent. In other words, tomaintain its liveweight, thesheep will require 20 per centmore energy each day than asheep with water close by andgrazing flat land.

The need for extra mainte-nance energy under certainproduction conditions such asthose described above becomeparticularly important when wewant to get sheep to specific tar-get weights for milk and meatproduction. Part of the reasonwhy weaners grown for primelamb production grow faster ina feedlot is because they expendless energy searching for foodand more energy growing thanlambs produced on pasture

alone. Another reason is thatlot-fed lambs also tend to begiven a feed ration capable ofsupporting high rates of growth.

Once the energy require-ments for maintenance havebeen met, the sheep can usethe additional metabolisableenergy from the diet forproductive processes such asmeat, milk and wool production.Thus, the metabolisable energyintake required for productionis principally determined bythe desired growth rate orlevel of milk production. Forexample, lactating ewes requireat least double their normalenergy intake to produceenough milk to sustain thegrowth of their lamb/s.

ProteinNon-ruminant animals rely

solely on the protein in their dietto produce proteins such asmuscle and enzymes withintheir bodies. Consequently, ifprotein is deficient in the diet,the animal will have insufficientprotein for these processes.

Ruminants have an adv-antage over non-ruminantsbecause the microbes in therumen are able to produceprotein from non-protein nitro-gen as well as from the proteinin their diet.This means that themicrobes can use nitrogen in theform of urea or sulphate ofammonia to make microbialprotein. When these microbesare eventually digested in thesmall intestine of the sheep, thisnon-protein nitrogen ultimatelyprovides the sheep with protein.This is particularly useful whensheep are grazing diets low inprotein such as straw stubbles.





However, when the crudeprotein content falls belowseven per cent, the microbes inthe rumen are not able toreproduce themselves and thepopulation begins to decline. Asthe microbial population falls,fewer microbes are available tobreak down the carbohydratesentering the rumen and in con-sequence the feed intake andgrowth rate of the sheep startsto drop off.

Growing sheep needbetween 12 and 15 per centcrude protein in their diet whilesheep fed for maintenance onlyneed about 8 per cent. Lupinscan contain 30 to 40 per centcrude protein and it wouldtherefore be wasteful to feedlupins alone since up to 65 percent of this lupin protein couldbe wasted in the urine of thesheep.The aim with protein sup-plementation is to feed enoughprotein to raise the protein con-tent of the base feed andthereby stimulate the feedintake (and therefore energyintake) of the sheep.

One of the disadvantagesassociated with the rumenmicrobes is that they fullydegrade much of the proteinentering the rumen into ammo-nia. This ammonia can be resyn-thesised back into microbial pro-tein but any excess ammonia isabsorbed into the sheep’s bloodstream with much eventuallybeing wasted when it is excretedin the urine as urea.

When the feed is low in pro-tein the amount of nitrogenexcreted in the urine is relatively

low. However, diets high inprotein cause more ammonia tobuild up in the rumen and, inconsequence, much of theincoming protein is wasted inthe urine of the sheep.

Microbial protein producedin the rumen travels to thesheep’s small intestine where itis broken down yet again intoamino acids that are absorbedinto the blood stream of thesheep for subsequent proteinsynthesis. All these processes areenergetically inefficient andsome of the protein entering therumen is consequently wastedbecause of this inefficiency.

Some heat and chemicaltreatments will protect proteinsfrom attack by the rumenmicrobes. These protected pro-teins ‘by pass’ the rumen and arefully available for digestion inthe small intestine. Canola mealis a good example of a proteinsource that is partially protectedduring the canola oil extractionprocess. Trials have shown thatincluding some of the proteinsource as canola meal leads tosmall increases in the efficiencywith which feed is converted toliveweight. Some commercialpellet formulations include aproportion of the protein ascanola meal. It is only likely to beeconomic to use a source of pro-tected protein if the differencein price between the protectedand unprotected protein sourceis small.

MineralsWhile protein and energy

are the major nutrients thatlimit animal growth, certain

minerals can also reduceproduction if they becomedeficient, particularly in fast-growing production animals.Macro-minerals are thoseneeded in relatively largeamounts (grams per kilogram)and include calcium, chlorine,magnesium, phosphorus, potas-sium, sulphur and sodium. Traceminerals such as cobalt, copper,iodine, iron, manganese, molyb-denum, selenium and zinc areneeded in much smaller amounts(milligrams per kilogram).

The intake of minerals bysheep varies throughout theyear. Adult sheep tend to haveenough reserves of minerals toprovide for their own needs andthose of the foetus during tem-porary seasonal deficiencies.However, animal reserves ofminerals will be depleted whenthey are fed only a grain-baseddiet for more than one month.Periodic feeding of a multi-min-eral and vitamin mix will beneeded for any long-term feed-ing in feedlots.

All grains are low in calciumand have relatively high levels ofphosphorus leading to a calciumto phosphorus ratio well belowthe ideal of 2:1. An imbalance ofcalcium and phosphorus whilefeeding grain can lead toreduced appetite and growth,soft bones and fractures, and theformation of urinary stones thatmay obstruct the urinary tract,especially in wethers and youngrams. If urinary stones do blockthe urinary tract this can leadto rupture of the urinarybladder, leakage of urine intothe abdomen, and the fatalcondition called “water belly”.

To avoid all these problems it isrecommended that 1.5 per centof finely ground limestone beadded when feeding cerealgrains to sheep.

Trace element deficienciesare more severe in foetuses andyoung animals. Newborn lambs,pre-ruminant lambs, and wea-ned lambs may not get enoughtrace elements for optimumhealth and growth duringseasonal deficiencies.

The trace elements mostlikely to be deficient in WesternAustralia are selenium, cobaltand copper. Selenium deficiencyis most often encountered inwinter and spring (in lambsand calves) and summer andautumn (in weaner sheep).Cobalt and copper deficienciesusually occur in spring, particu-larly in years with rapid pasturegrowth after good winter rains.Oral drenches and injectableproducts are available for theprevention and treatment ofdeficiencies of each of these ele-ments, and intra-ruminal pelletsare available for the preventionand treatment of selenium andcobalt deficiencies.

Adding selenium and copperto fertilisers used to top-dresspastures will prevent deficienciesof these elements in grazingstock. Selenium, cobalt andcopper are all included in mostmineral supplements. Seleniumdeficiency may cause nutritionalmyopathy (“white muscle dis-ease”) in young sheep, but thesame condition can also resultfrom a vitamin E deficiency.The actual cause needs to bedetermined to ensure the correcttreatment is provided.

Copper deficiency in live-stock may also result when cop-per in the diet appears to be ade-quate, but there are high levelsof molybdenum and/or sulphur.The molybdenum and sulphurinteract with the copper andmake it less available for absorp-tion from the digestive tract.

VitaminsVitamins of importance in

ruminant nutrition are either fator water-soluble. The fat-solublevitamins include vitamins A, D, Eand K and the water-solublevitamins are those in the B groupand vitamin C. Green pasturesgenerally contain adequate levelsof vitamins A, E and K for sheepand vitamin D is synthesised inthe skin provided animals areexposed to enough sunlight.

Sheep usually synthesiseenough vitamin C to meet theirrequirements and the microbesin the digestive tract are usuallyable to synthesise adequateamounts of the B-group vita-mins. Cobalt is required for thesynthesis of vitamin B12 by therumen microbes and cobaltdeficiency shows as a deficiencyof vitamin B12 with the maineffect being a disturbance inenergy metabolism leading toreduced growth in young animals.

Vitamin A deficiency canoccur after prolonged dry periods.Sheep need to eat green feed,suchas weeds, for at least a day to getenough vitamin A to last for threemonths. Some feeds, such as sub-clover and lucerne, have highervitamin A levels.

Thiamine (vitamin B1)deficiency is usually caused bythe presence of the enzyme

“thiaminase", which is ingestedin certain plants or is producedby microbes in the rumen.Thiaminase destroys the thi-amine entering and produced inthe rumen, and deficiency of thisvitamin leads to the develop-ment of a neurological disease.A change to a high-grain diet mayprecipitate thiamine deficiency,and the condition has alsobeen reported in sheep fed dietsthat have insufficient fibre toencourage good rumen motility.

Vitamin E, like selenium, hasa major role as an anti-oxidantand the metabolic roles ofvitamin E and selenium areinterchangeable to some extent.

Sheep that have experiencedreasonable lengthy periods ongreen feed and are only fedconcentrated diets for shortperiods are unlikely to experi-ence mineral and vitamindeficiencies. However, if younganimals have only had a shortperiod of access to green feed, orhave been off green feed for morethan three months, their bodyreserves are likely to be low.

Periods of rapid growth,pregnancy and lactation, gener-ate high demands for mineralsand vitamins and animals withlow body stores may becomedeficient if they are not able toobtain all the vitamins andminerals they need from theirfeed source. Feed produced inhigh rainfall environments tendto have lower levels of vitaminsand minerals because theirconcentrations are diluted inthe fast growing plants.



PA ST U R EGrazing annual pastures

Pastures in the Agricultural Area

Sandplain lupins. A good feed for lambs

Grazing saltland pastures

Dryland lucerne grazing systems

Tagasaste (fodder shrub)

Native perennial grasses in permanent pastures

Subtropical perennial grasses

Summer fodder crops


PA ST U R E

K E Y M E S S AG E Só Animal production is directly related to the quality and quantity of the pasture the

animals graze.ó The estimation of ‘feed on offer’ (FOO) can be used as a guide to manage both

pasture and animal production.ó For pasture, near-maximum seed production occurs when spring FOO exceeds

4000 kilograms dry matter per hectare. However, FOO of 1300 kilograms dry matter per hectare can provide enough seed to establish a good sub-clover pasturethe following year.

ó Near-maximum liveweight gain for sheep will occur when FOO is greater than 2000 kilograms dry matter per hectare. However, a FOO of more than 1100 kilograms dry matter per hectare will still provide some liveweight gain.

ó Sheep growth is directly correlated to the digestibility of pasture feed.ó Digestibility decreases considerably as a pasture matures.

Keith Devenish, Department of Agriculture, Northam andMike Hyder, Department of Agriculture, Albany

Grazing Annual Pastures

IntroductionAnnual pastures are the

most important source of feedin the Mediterranean environ-ment of the agricultural regionof Western Australia. They con-sist mainly of grasses, broadleafweeds and legumes. Thesepastures play an importantpart in the farming system as afeed source for the sheep meatenterprise. Annual pasturescan be divided into high valuegreen feed and lower valuedry feed.

DigestibilityDigestibility is the most

important characteristic ofannual pasture because thisinfluences the amount that a

sheep can eat as well as howfast it will grow. Digestibility,expressed as a percentage,provides a prediction of theproportion of the pasture con-sumed that is actually used bythe animal. In winter andspring, the digestibility ofgreen feed is high (70 to 80 percent) but this value declinesrapidly as pastures mature anddry off. Once digestibility fallsbelow 50 per cent, even adultsheep will not be able to main-tain their weight.

Green feedThe growth rates of young

or adult sheep during winterand spring should be in thevicinity of 1.5 to 2.0 kilograms

per head per week once thereis ample green feed available(or until they reach their peakweight according to their age).The supply of green feed isoften limited at the start ofthe growing season and con-sequently the growth rate forsheep is low. The slow growthof pastures during June andJuly can be attributed tolow levels of light, a low leafarea index, waterloggingand frosts.

Sheep feed is usually inabundance towards the end ofthe growing season and duringthe traditional spring flush.At this time, growth rates ofsheep are as close to the maxi-mum as possible.

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suckers into November. Thoseanimals not sold as suckers arethen weaned and are oftenshorn. During this period theywill require additional manage-ment as they begin to graze ondry pasture feed.

Dry feedFor young sheep, a dry

annual pasture with about 50

per cent legume content canonly provide growth rates of oneto two kilograms per head permonth for one to two months,because it is only slightly above amaintenance ration. The rate ofgrowth for weaners can varyconsiderably from December toApril with the digestibility of dryfeed being the main influenceon animal growth.

The dry residues of annualpastures like sub-clover, medic,and serradella, along withweeds such as ryegrass andcapeweed, usually have adigestibility of about 55 per centat the start of summer.This levelcan vary considerably and willdecline over time, especiallyafter rainfall. Dry feed with adigestibility below 55 per centwill at best only maintainliveweight and supplementaryfeeding with grain will berequired to finish animals beingproduced for meat.The period ofhigh quality pasture can beextended by spray toppingpasture with a knockdownherbicide in spring.

Both the quantity and tim-ing of rainfall events are majorfactors affecting pasture pro-duction. However, soil type,fertiliser application, grazingmanagement and pasturespecies can also have a biginfluence on pasture growth.A rule of thumb is that 20 kilo-grams of pasture (weighed dry)per hectare should be grown permillimetre of growing seasonrainfall. The length of the grow-ing season, and hence the periodof green feed, can also be influ-enced by the position in thelandscape, the soil type andlocality within each respectiverainfall zone.

The major production ofsucker lambs is usually matchedto the winter and spring periodby selling lambs straight off theewes during the green feedseason. These sales are usuallybetween June and October,with southern areas producing

Dry barley grass has a very low digestibil-ity and feed value over summer.

Merino ewes rearing sucker lambs on subterranean clover based annual pastureat Pingelly.

Case example

The results from a summergrazing trial conducted atPerenjori in 1996/97 provide agood example of the limitationof dry feed for young sheep. Inthis trial (see section “Increasinglamb growth on medic pasturecover cropped with lupins”)crossbred weaner lambs in thecontrol treatment grew at lessthan half a kilogram per headper week on a dry legume pas-ture (more than 80 per centmedic) from December toJanuary. In this trial the qualityof feed was good and had notbeen spoilt by summer rain. Thisresult highlights the need tosupplementary feed at this timeto improve animal growth.

Supplementary feeding insummer

If growth rates of lambs orweaners are to be maintainedduring summer on annuallegume pastures, then supple-mentary feeding will berequired. A high quality grain,such as lupins fed at 100 to 400

grams per head per day, will helpproduce a reasonable growthrate for meat sheep (one kilo-gram per head per week).

Another strategy may be tofeed less grain and maintainliveweight during this perioduntil crop stubbles, such as thosefrom lupins, become available.

Weaning lambsFor prime lamb production

(after the sucker stage), the firstmajor setback can occur if thelambs are weaned as pasturesdry off. During this critical time,grain should be fed to at leastmaintain the weight of theweaners and eliminate thesetback. Weaners should bepre-trained while still on theirmothers to recognise whatevergrain is fed as a supplement.This usually means trail feedingthe ewes and lambs two or threetimes before weaning so thatthe lambs recognise the grain asa feed source.

Feed On Offer (FOO) -an indicator formanagement

Grazing research has shownthat estimating the amount ofFOO is a useful indicator for themanagement of both pastureand sheep. It is expressed in kilo-grams of pasture dry matter perhectare. The technique of esti-mating FOO is a practical skill


PA ST U R E

Table 1. Prograze feed on offer (FOO) benchmarks for sheep (kg DM/ha)

that can be readily learnt from aWoolpro or Prograze adviser (orlivestock consultant) and can beused as a guide to predict sheepgrowth rates. Most of the workon FOO and sheep performancehas been done with sub-cloverbased pastures.

The critical factor determin-ing the production level of live-stock grazed on pasture is theamount of pasture that animalsare able to eat, otherwise knownas intake.There is a range of FOOthat can result in the desiredintake and subsequent produc-tion for sheep. If FOO dropsbelow a certain level, sheep areunable to consume sufficientpasture to maintain liveweight.

The Prograze manual sug-gests that once FOO is less than1100 kilograms dry matter perhectare the rate of feed intake isreduced and sheep can only beexpected to maintain weight orat best, make very slow weightgains (Table 1). Near-maximumfeed intake for sheep occurs ataround 2000 kilograms dry mat-ter per hectare and there is nosignificant advantage allowingmore than this amount of FOOfor sheep.

Hence, as a general rule, themessage is “2 tonnes of feed is allthey need”.

Grazing managementOvergrazing of annual pas-

tures in autumn can lead to asignificant reduction in pastureseedling density, especiallywithin the first 12 days after thebreak of season. As a result, theproductivity of pastures duringwinter will be lower becausethere are fewer plants.

Hoggets Dry sheep Pregnant Lactating ewes ewes

(35-40 kg) (50-55 kg) (50-55 kg) (50-55 kg)

Slow increase in liveweight 1000-1200 800-900 1000-1200 1200-1400

Near maximum increasein liveweight 1800-2000 1800-2000 2000-2500 2000-2500


PA ST U R E

For sub-clover pastures,grazing to a FOO of at least1100 kilograms dry matter perhectare during spring willensure enough seed is set forthe next pasture season. Nearmaximum seed-set occurs whenFOO exceeds 4000 kilograms drymatter per hectare.

To maximise the seed set ofsub-clover, the options are to:ó defer grazing pasture at the

break-of-season until FOO isat least 500 to 800 kilogramsdry matter per hectare;

ó maintain winter pasturesbetween 1500 to 2500 kilo-grams dry matter perhectare FOO;

ó de-stock pastures when dryFOO has decreased to 1000

kilograms dry matter perhectare in summer/autumnFor aerial seeded species

such as medic, serradella,biserrula and other clovers(eg balansa, Persian, rose),similar management willassist in long term persistence.The most important issue isto reduce grazing pressureat the start of floweringuntil seed maturity. Reducedgrazing pressure is mainlyrequired when FOO levels areless than 2000 kilograms drymatter per hectare.

Seasonal variability inannual pasture growth

The pattern of feed supplyin different rainfall zones isshown schematically in Figure 1.The timing of the break-of-sea-son has a large effect on thesupply and the total dry matter

production in each season. Thereduction in growth during Juneand July occurs largely as aresult of a lower amount of lightenergy being available for pho-tosynthesis as well as low soiltemperatures. Pasture growthtends to increase during Augustwith the availability of morelight energy.

Under conservative stock-ing regimes, large amounts ofhigh-quality FOO accumulateduring spring. Up to 75 per centis lost after ‘haying-off’ (senes-cence) due mostly to naturaldecay. In other words, very littleis eaten by grazing animals andturned into wool or meat prod-ucts. Using more of this spring

FEEDONOFFER(TONNESDM/ha)

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Figure 2. Feed on offer profiles (insects controlled) under district average set-stocking rateof 8 wethers per hectare at Mt Barker Research Station between 1992 and 1994.

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M A M J J A S O N D J F M

Figure 1. Schematic representation of green feed on offer or FOO, in low (300 mm),medium (500 mm) and high (700 mm) rainfall zones.

“hump” by combining grazingmanagement and conservationtechniques is one way to imp-rove the productivity of pasturesystems in a Mediterraneanenvironment.

The variation in the timingof the break-of-season resultsin different amounts of FOOduring winter (compare theamount of FOO in Figure 2 afterthe break in 1993 with that in1994). The FOOs peak at differ-ent amounts in spring and thensharply decline over the follow-ing summer and autumn peri-ods. Often only a small percent-age of the accumulated FOO atthe end of spring is convertedinto meat or wool.


PA ST U R E

Grazing management tocontrol insects

Redlegged earthmite (RLEM)and other pasture pests (blue-green and cowpea aphid, lucerneflea, blue oat mite) can causelosses of up to 80 per cent oflegume pasture seed if they arenot controlled. This loss occurswhen seedlings are killed early inthe season and when flowers aredamaged during spring.

Research has shown thatgrazing pastures to a FOO levelof 1400 kilograms dry matterper hectare during springreduces RLEM numbers consid-erably. The benefits from pestcontrol in spring, whetherby grazing management orcorrectly timed applicationsof insecticide (TIMERITE®, theKondinin Group can provideinformation on this package),usually carry over to thefollowing year.

CroppingThe adverse effects of crop-

ping on pasture legume seedreserves are well documented.Seed loss after one year of crop-ping with relatively softer-seededspecies such as sub-clover canbe as high as 70 per cent whilehard-seeded species such asmedic and yellow serradella loseabout 30 per cent of their seedreserves after one crop.

Sub-clovers are better adap-ted to longer pasture phasesthan medics. Medics and yellowserradella will persist better inintensive pasture-crop systemslike the year-in year-out rotation.

Tactics for pasturemanagement

There are a number of tac-tics that can be used during theseason to manage the variationin the supply of pasture. Theseare described in the Woolpro orPrograze manuals, or alterna-tively you can contact your localWoolpro or Prograze adviser formore details.

Further readingHyder, M.W.; Thompson, A.N.;Doyle, P.T. and Tanaka, K. (1994).The effect of feed on offerduring spring on liveweightchange in Merino wethers ofdifferent ages. Proceedings ofthe Australian Society of AnimalProduction 20:255-8.

PROGRAZE Sustainable GrazingManual.

WOOLPRO Reference Manual.

PA ST U R E

Pastures in the Agricultural Area


K E Y M E S S AG E Só The environment and the farming system determine how suited a pasture species

is to a particular area.ó Pasture species vary widely in their seasonal pattern of feed production

Trevor Lacey, Keith Devenish and Clinton Revell,Department of Agriculture, Northam

There are environmentaland management factors thatdetermine where particular pas-tures will perform best, includ-ing length of growing season,soil pH, cropping intensity andwater availability.

Self-regenerating annualpastures like sub-clover, medicand yellow serradella, arebest adapted to intensive crop-ping systems.

Pasture systems are nowevolving to include short peri-ods of ‘phase’ pastures inbetween periods of continuouscropping. Phase pastures mayalso include self-regeneratingannual species but the use oflonger periods between cropsalso allows the use of perennialspecies such as lucerne.

Work through Table 1 toidentify the pasture optionsthat are best suited to your spe-cific environment. For detailedvariety recommendations seethe Farm Budget Guide.

Table 1. Pasture options for different environments

Additional Soil Permanent pasture Intensive moisture types and phase pasture croppingavailability systems rotations

Yes Light Perennial grass, lucerne, Serradella, sub-clover,tagasaste, blue lupins, biserrula,serradella, biserrula, warm season fodder cropssub-clover, arrowleaf clover,warm season fodder crops

Medium Lucerne, perennial grass, Serradella, sub-clover,saltbush, sub-clover, biserrula, balansa clover,serradella, biserrula, persian clover,crimson clover, warm season fodder cropsbalansa clover, persian clover,warm season fodder crops

Heavy Lucerne, perennial grass, Medic, balansa clover,saltbush, medic, persian clover,balansa clover, warm season fodder cropspersian clover,warm season fodder crops

No Light Tagasaste, blue lupins, Serradella, sub-clover,serradella, biserrula, biserrulasub-clover, arrowleaf clover

Medium Lucerne, perennial grass, Serradella, sub-clover,saltbush, serradella, biserrula, balansa clover,sub-clover, biserrula, persian clovercrimson clover,balansa clover, persian clover

Heavy Lucerne, perennial grass, Medic, balansa clover,saltbush, medic, persian cloverbalansa clover,persian clover


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Seasonal feed availabilityIn working out manage-

ment strategies for sheep meatproduction it is important toconsider the availability of feedduring the year. As is shown inTable 2, there is considerablevariation in the availability offeed for optimum production.

Table 2. The seasonality of the availability of pastures as a source of feed for sheep

Pastures Availability of feedsJan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Annual pasture ** ** * * * *** *** **** **** **** *** ***

Long season annual pasture (e.g. serradella) *** ** * * * *** *** *** **** **** **** ***

Lucerne *** *** *** *** *** *** *** **** **** **** **** ***

Perennial grasses (summer-active) *** *** * * * * * * *** *** **** ****

Saltland pastures mix (halophytes, perennial grasses and balansa) ** ** ** ** ** *** *** **** **** **** *** ***

The suitability of the part-icular feed will vary withfarm location and rainfall. Theincreased availability of mois-ture (ie summer rainfall, groundwater discharge,) will increasethe feed availability from peren-nials and warm season crops,but will adversely affect thequality of pasture residues.

Further readingMaximum meat: the completeguide to producing qualitysheep meat. Department ofAgriculture. 1998.

Pasture legume recommenda-tions. Farm Budget Guide,Farm Weekly.

* Low quality, low quantity - unlikely to provide maintenance.** Low quality, high quantity - likely to provide maintenance for dry sheep only.*** High quality, low quantity - likely to provide maintenance and a low growth rate (short period)**** High quality, high quantity - most likely to produce maximum growth rate.

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Sandplain Lupins; a Good Feedfor Lambs


K E Y M E S S AG E Só Sandplain lupins are a cheap, nutritious source of feed for the summer/autumn period.ó Sandplain lupins can be grazed for three to four months at a stocking rate of 10 to

15 sheep per hectare, to achieve weight gains of up to 100 grams per head per day.ó Weaners need to be monitored closely for signs of lupinosis and if it develops they

need to be taken off the lupins, grazed on other pastures and not be given lupin seed.

Keith Croker, Stewart Gittins, Grant Doncon andJeremy Allen, Department of Agriculture, South Perth

Sandplain lupins (alsoknown as WA blue lupins) wereaccidentally introduced intoWestern Australia in the latenineteenth century. Since thenthey have become naturalisedand grow on poor sandy soils inthe West Midlands where it isdifficult to get other productivepasture species to grow. Theselupins are hard seeded, self-regenerating plants.

Available feedStands of sandplain lupins

are very variable in mass andcomposition from site to site,and between years, but usuallyhave high amounts of dry mat-ter (more than five tonnes perhectare) at the start of summer.This material consists of lupinpods and stems, an understoreyconsisting of lupin leaf material,grasses, clover and weeds, andlupin seed. The seed has a highcontent of crude protein (about32 per cent) and a high in vitrodigestibility (about 80 per cent)

but contains variable quantitiesof quinolizidine alkaloids thatmay give it a bitter taste.

Grazing potentialGrazing experiments over

four consecutive summer/autumn periods (1994/95 to1997/98) at Badgingarra demon-strated that sandplain lupins canbe successfully used as a valu-able feed for Merino weaners(see Figure 1).

Over the four-year period,the composition and density ofthe lupin stands varied consid-

erably, but no significant rainswere encountered during any ofthe grazing periods. In all yearsthe weaners grazed the lupinsfor three to four months fromearly December. During threeof the years, the weaners graz-ing at the lowest stocking rate(five per hectare) gained about75 grams per head per day whileon the lupins.

In December 1998, the per-formance of Border Leicester xMerino weaners grazed on sand-plain lupins on a farm at Eneabbawas monitored.

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Figure 1. Liveweight gain of Merino weaners grazed on sandplain lupins at Badgingarrafrom early December 1997.


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The paddock and sheep hadbeen subject to the farmer’susual management practicesduring winter/spring.The wean-ers were put into the paddockat the beginning of December.The size of the flocks wasadjusted to produce a stockingrate of 10 per hectare, which,based on previous results, wasexpected to enable reasonablegrowth over an extended periodin summer/autumn.

The July-born weaners hadbeen vaccinated at weaningagainst cheesy gland, pulpy kid-ney and tetanus.The vaccine con-tained selenium and the wean-ers were also given an injection ofvitamin B12. They were drenchedwith Ivomec® when put into thelupin paddock. The weanersstarted the grazing period withan average liveweight of34 kilograms, and gained about10.5 kilograms over the subse-quent 105 days. This was agrowth rate of about 100 gramsper head per day (see Figure 2).

Ninety per cent of theweaners were sent to theMidland Saleyards at the end ofgrazing of the sandplain lupins(10 per cent were considered tohave not reached a saleable

weight). The sheep averaged25.5 dollars per head.

This work has demonstratedthat, in the absence of significantsummer rain, crossbred weanerscan make substantial gains inweight over three months whilegrazed on stands of sandplainlupins, during a period whennormal paddock pastures can-not maintain significant ratesof growth. This growth wasobtained at a minimal cost usinga feed resource that is oftenunder-used or neglected.

Problems to avoidIt is important that sheep

grazed on sandplain lupins bechecked regularly, especially latein summer and autumn, to min-imise the risk of the developmentof lupinosis, and to avoid over-grazing with the consequentexposure of the soil to winderosion. If lupinosis develops inweaners,growth rates are greatlyreduced. Regular checks enablethe early detection of lupinosis,and the sheep can be taken offthe lupins before losses occur.

The amount of material onthe ground needs to be moni-tored so that the paddocks don’tbecome a potential erosion risk.

Moving the water point beforethe surrounding area is toobare will give better use ofthe feed while reducing the ero-sion potential.

Note: Sandplain lupins arevery susceptible to the diseaseAnthracnose that has been evi-dent in Western Australia lupincrops since 1996/97. Increasingprevalence of this disease inWestern Australia is likely toreduce production from sand-plain lupins. The expansion ofthe area of sandplain lupins andassociated increased source ofAnthracnose inoculum is notencouraged because this wouldincrease the risk of disease inthe white lupin industry.

Further readingBlake, J. and Nelson, P. (1989).Sandplain lupins. WesternAustralian Department ofAgriculture Farmnote 47/89.

Gittins, S.; Doncon, G.; Croker, K.and Allen, J. (1999). Blue lupins:a better use for an old feed.Ovine Observer, No. 8, Sep 1999.

Morcombe, P. (1989). The sand-plain lupin: its nutritional valueand grazing management.Journal of Agriculture, WesternAustralia 30, 108-110.

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Figure 2. Weight gain of crossbred weaners grazed at 10 head per hectare on sandplainlupins at Eneabba from early December 1998.

Merino weaners grazing dry sandplainlupins at Badgingarra.

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Grazing Saltland Pastures


K E Y M E S S AG E Só Animal production is directly related to the quality and quantity of the pasture the

animals graze.ó Young sheep will gain weight on good, mixed saltland pastures containing annual

pasture species but will usually lose weight on saltbush alone.ó Weaners will grow at up to 100 grams per day (0.7 kilograms per head per week)

during summer without supplementary feeding on saltland pastures growing in areas with low salt levels and consisting of a good mix of halophytes and balansa and persian clovers.

ó A good quality water supply with low salt content is required when grazing sheep on diets with high levels of salt as sheep will drink up to 7 litres per day.

Trevor Lacey, Department of Agriculture, Northam

IntroductionThere is little information

about the production of sheepmeat from saltland pastures inWestern Australia.

Saltland pastures are bestreferred to as a combination of:ó Perennial salt tolerant

shrubs known as halophytes(eg. saltbush and bluebush)that have the ability to accu-mulate salt in their leaves;lower the water table; andalter the micro-environmentto allow the establishmentof other plant species, and;

ó Perennial grasses andannual pasture legumessuch as puccinellia, tallwheat grass, balansa andpersian clovers. These peren-nial grasses and annuallegumes provide the bulk offeed in saltland pastures and

when green are preferen-tially grazed. For more infor-mation on annual pasturesand perennial grasses referto the sections in this book.

Costs of establishingsaltland pastures

The costs associated withdeveloping saltland pastures canbe highly variable and largelydepend on the amount of capitalinfrastructure required, such asfencing, water supplies and sur-face drainage, as well as theestablishment costs of the newpasture species. The capital costsshould be spread over the life ofthe saltland pasture when deter-mining the total cost of estab-lishing the pasture.

The capital cost of estab-lishment is often high. However,there is little cost in the form of

lost productivity, as most of thisland is currently unproductive.Michael Lloyd, a farmer at LakeGrace, has estimated the costsfor direct seeding saltlandpasture to be 170 dollars perhectare (contract) or 55 dollarsper hectare (sown by thefarmer).The costs of fencing andproviding water are additional.

Where to grow saltlandpastures.

Saltland pastures are gen-erally grown on land wheresalinity and waterlogging affectthe production and profitabilityof salt-sensitive grain cropsand pastures. The selection ofspecies is dependent on rainfall,degree of waterlogging andlevel of soil salinity at each spe-cific site. Areas of high salinityand waterlogging favour the


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poorer quality and more salt tol-erant species such as the salt-bushes. These areas are not wellsuited to high-quality stock feedsuch as balansa and Persianclovers and the grasses; tallwheat grass and puccinellia.However, often the establish-ment of the more salt tolerantspecies will lower the watertable sufficiently to allow leach-ing of salts and the subsequentestablishment or colonisationby less salt tolerant species withhigher grazing value.

Grazing managementSaltland pastures need to

be managed to protect therange of species in the stand.Where there is a mix of bothperennial and annual speciesthe requirements of each needto be considered. The balansacomponent of the pasture willbe dependent on the availability

of seed and fertiliser and mayrequire the control of insects.Therefore, saltbush plantingswill need to have row spacingwide enough to allow access forvehicles to apply fertiliser andinsecticides.

Rotational grazing is rec-ommended for the long-termpersistence of perennial plants.This should be combined withreduced grazing during flower-ing periods of balansa and per-sian clover, along with a periodof heavy grazing during sum-mer and autumn to remove thebulk of dry matter and helpincrease the seed softeningprocess. All this is requiredwhilst leaving leaf on the halo-phytes to increase water use.

Quantity of feed and itsavailability

The saltbush component ofsaltland pastures produces rela-tively low levels of digestiblematerial. A three-year trial atKatanning with four varieties ofsaltbush showed that saltbushhad an average annual yield ofleaf and fine stem material ofless than 500 kilograms of drymatter per hectare. In this trial,the bulk of the feed came fromthe poor-quality annuals suchas barley grass, and other salt-tolerant natural species pre-sent, in addition to the plantedperennial grasses.

The bulk of feed availablefrom saltland pastures will usu-ally be from late autumn throughto early summer. Additional feedfrom the perennial grasses andperennial salt-tolerant shrubs (for example, saltbush and blue-bush) may be available during

the summer and autumn, butthis depends on the availabilityof moisture.

The value of this perennialfeed during summer andautumn is very high comparedto that available at other timesof the year. These pastures mayoffset the need to supplemen-tary feed stock through theautumn, and thus enable graz-ing to be deferred on newly ger-minated annual pastures. In thisway, higher stocking rates can beused across the whole farm.

Quality (energy, proteinand digestibility)

Grazing trials at Katanninghave shown that saltbush aloneis of limited value because highsalt concentrations reduce thedry matter intake and digestibil-ity of the material.The quality ofthis material may vary depend-ing on the salinity of the site andthe occurrence of rainfall thatallows salt to be washed fromthe leaves.

Old man saltbush growing in a saline andwaterlogged area in Cuballing.

Mixed sward of Balansa and Persianclover growing on a winter waterloggedbut not excessively saline area.


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The quality of the pasturescan be improved by plantingother grass and clover species inthe inter-row. For example, puc-cinellia and tall wheat grasshave higher digestibility, lowersalt levels and higher animalintake than saltbush, but theyare not high quality feeds.Balansa and Persian clovershave a higher quality evenwhen dry. However, the salt con-tent of balansa can be high andthis will reduce sheep intakewhen it is grown on severely saltaffected land.

Sheep meat productionfrom unimproved saltland pas-tures (for example, halophytesand barley grass) is rarely high.At best these pastures will pro-vide maintenance diets, cer-tainly for young sheep, but usu-ally these sheep lose weight onsaltbush pastures. Improvedsaltland pastures with good bal-ansa and Persian clover as a sig-nificant proportion of the mixwill grow weaners at up to 100 grams per day (0.7 kilogramsper head per week) over sum-mer without supplementation.However, to do this the cloversneed to be grown on areas withlow salt levels in the soil,although these areas may beprone to winter waterlogging.

Economic returns The returns from meat pro-

duction on saltland pastureshave not been well establishedand will vary from case to case.The best returns are likely to beobtained where substantialincreases in stocking capacityare achieved through the conver-sion of very low performing land

to land with a much higher pro-duction level and in the reduc-tion of some supplementaryfeeding costs. Capital costs suchas fencing and the provision ofadditional water points associ-ated with the use of saltland pas-tures can often determine theprofitability of these pastures.Where high quality annual pas-ture and perennial grasses are asignificant part of the pasture,returns from meat productionare similar to that obtained onnormal annual pastures.

Michael Lloyd, a farmer atLake Grace, estimated the grossmargin for a wool enterprisebased on a saltland pasture atabout 75 dollars per hectare.

It has been noted that thereis a positive effect on the flavourof meat produced from sheepgrazing saltland pastures. As aresult of this effect, there havebeen attempts to market meatproduced on saltland pasturesas a high-value premium prod-uct. However, a significant andreliable market for this type ofmeat has yet to be developed.

Provision of goodquality water

High levels of salt in saltbushpastures cause sheep to drink upto seven litres of water per day,twice the water consumption bysheep on low salt diets. Thismeans that there needs to be aplentiful supply of good qualitywater when sheep are grazed onany saltland pastures.

Further reading Barrett-Lennard, E.G. (1998).“Halophytes or plants for salt-land”. Soil Guide. Departmentof Agriculture, Bulletin No 4646.

Barrett-Lennard, E.G. andMalcolm C.V. (1995). “SaltlandPastures in Australia – APractical Guide”. Department ofAgriculture, Bulletin No 4612.

Warren, B.E.; Casson, P.A. andBarrett-Lennard, E.G. (1995).“Value of saltbush questioned”.Journal of Agriculture, WesternAustralia 36: 24-27.


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K E Y M E S S AG E Só Lucerne grows in a wide range of environmental conditions and soil types

throughout Western Australia.ó Lucerne can produce feed with a quality and quantity equal to or better than sub-

clover, and will provide green feed for a longer period.ó Green feed is generally available from April to December and at various periods

throughout summer and autumn depending on moisture availability.ó Lucerne has produced growth rates for one-year-old sheep of 1.3 to 1.75 kilograms

per head per week.ó The use of lucerne offers an opportunity to finish meat sheep out of season for

premium markets.

Trevor Lacey and Keith Devenish,Department of Agriculture, Northam

Costs of establishmentEstablishing lucerne in the

Western Australian wheatbelthas been commonly quoted atcosting between 80 to 100 dol-lars per hectare. This cost can bespread over the life of thelucerne stand, or the length ofthe lucerne phase in a lucerne-crop rotation. It is often acceptedthat the costs of lucerne estab-lishment can be spread over theperiod for which benefits arederived within the croppingphase. Therefore, in a four-yearlucerne phase, the cost of estab-lishment can be calculated to be20 to 25 dollars per year of therotation.The cost of establishinglucerne is comparable to that ofestablishing a good legume-based annual pasture.

Where to grow lucerne Lucerne requires at least

250 millimetres annual rainfallto persist. Data from Pingrup(320 millimetres rainfall) foundthat lucerne produced 4 to6 tonnes per hectare of dry mat-ter per year, which was equal toor greater than that for a sub-clover pasture. The level of pro-duction achieved with anannual rainfall less than320 millimetres has not beenwell defined. Lucerne grows on arange of soil types and pH (seethe bold in Figure 1), but is bestsuited to well-drained soils witha pH between 4.8 and 8.0 (CaCl2).

Figure 1. Soil suitability for lucerne.

Dryland Lucerne Grazing Systems

4 5 6 7 8 9

Poor

Sand

Good

Sand

Dupl

ex

Clay

Salin

e

Soil pH (CaCl2)

Soil Types

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Lime should be applied at one totwo tonnes per hectare wheresoil pH is between 4.8 to 5.2.

It should be noted thatFigure 1 is only a guide to wherelucerne performs best and thereare cases where lucerne is grow-ing outside these recommenda-tions for soil type and pH.

Winter active varieties oflucerne are preferred for drylandsowing in Western Australia.They have good fodder qualitiesand the persistence of the standis adequate for a four to five yearlucerne pasture phase.

Lucerne will grow on mod-erately saline soils. However,production is affected at rela-tively low levels of soil salinity,especially when it is comparedto a crop such as barley (seeTable 1). Barley has more salttolerance than wheat and isoften grown by farmers on soilsthat are marginal for graincrops due to salinity levels. Thisknowledge will help whendeciding where to grow lucerne.As a comparison, lucerne canhave a loss in production ofmore than 50 per cent at a soilconductivity of 90 milliSiemensper metre compared to a loss inbarley production of five to tenper cent.

Grazing managementstrategies for lucerne.

For best results, lucerneshould be rotationally grazed ifit is to persist in a grazing sys-tem. For sheep, the grazing rota-tion can vary from a three pad-dock system (lucerne grazed forthree weeks and rested for sixweeks), to a six paddock system(lucerne grazed for one weekand rested for five weeks).Stocking rates are adjusted sothat the dry matter is reduced tosimilar levels by the end of eachgrazing period (grazed to aheight of one to two centimetresor about 400 kilograms drymatter per hectare). The restingor ungrazed period enableslucerne to replenish its rootreserves, helping to maximiseproduction and allowing thepasture to survive over the drysummer months.

Extending the grazing peri-ods and reducing the restingperiods are possible under somefavourable growing conditionsand at lower stocking rates, orwhere there is additional feedavailable in the paddocks fromother pasture species (althoughthis may be at the expenseof total production). However,

adopting this practice in lessfavorable conditions may sev-erely affect the lucerne produc-tion by reducing plant numbersor weakening plants (with subse-quent plant growth reduced forthe following six to 12 months).

Availability and quantityof feed producedin a season

For an average rainfall sea-son, lucerne will provide greenfeed earlier in winter and extendthe availability of green feed atthe end of the growing seasoncompared to annual pasture.In the medium rainfall regionsof the central wheatbelt, it iscommon to graze lucerne intoDecember during a season withaverage rainfall.

The amount of summer(January to April) feed prod-uction depends on moistureavailability from either summerrain or from stored soil mois-ture. Lucerne can rapidly con-vert summer/autumn rainfallinto high-quality green feedwhereas summer rain willreduce the quality of dry feedand can cause a “false break” ofannual pastures.

Table 1. Production losses (per cent) in lucerne and barley with increased levelsof salinity

Crossbred lambs grazing lucerne atBuntine in April.

Soil conductivity (EC 1:5 (w/v)mS/m)20 40 90 150

Lucerne 0% 15 -20% > 50% 100%

Barley 0% 0% 5 -10% 35 - 45%

Adapted from Stanley and Christinat (1994)


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The quality of feed availablefrom lucerne remains relativelyconstant throughout the year.

A typical pattern of lucerneavailability in the 350 millime-tres rainfall zone is shown inFigure 2. This depicts the rota-tional grazing pattern sug-gested for a paddock of lucerne.The solid lines show the cumula-tive amount of pasture dry mat-ter available in kilograms perhectare of feed (on offer) for anaverage season. During themonths between January andApril the level of feed on offer isextremely variable with signifi-cantly more feed in a year with awet summer, or when soil mois-ture is not limiting.

The broken line in Figure 2represents a two-week period ofgrazing where the total feedavailable in the paddock isreduced to about 400 kilogramsdry matter per hectare. A conse-quence of this rotational graz-ing pattern is the requirementfor a number of lucerne pad-docks or alternative sources ofgood quality feed, to maintainproduction levels.

Lucerne pastures are capa-ble of producing levels of totalbiomass comparable to or betterthan good annual pasture (eg.sub-clover) over a 12-monthperiod. But the lucerne plantmaterial is considered to be ofmuch higher feed value due toits summer/autumn production.

Farmer experience in thewheatbelt suggests that thetotal carrying capacity onlucerne pastures is equal to, ifnot better than, good clover-based annual pastures. The dif-ference is that the longer periodof green lucerne feed during thelate autumn/early winter andlate spring/early summer peri-ods, can achieve growth ratesfor sheep as high as thoseobtained during the wintergreen feed period. In addition,the summer/autumn produc-tion greatly increases inresponse to summer rainfall.The significance of these attrib-utes to sheep meat productionis the flexibility to turn stockoff into high priced marketseither early or late in the normalgrowing season.

Lucerne feed quality Lucerne provides high qual-

ity feed for grazing animals. It ishighly digestible (about 65 percent) and is a reliable and eco-nomic source of crude protein(12 to 24 per cent) with goodlevels of metabolisable energy(8 to 11 megajoules per kilo-gram dry matter).

Stocking ratesTrials in the wheatbelt have

demonstrated that lucerne cansupport average district stock-ing rates while providing addi-tional green feed after annualpastures have matured. Farmerexperience shows that lucerne isa high quality source of greenfeed as long as it is grazed forshort periods of two to sixweeks. Set stocking is not advis-able for dryland lucerne becausesheep will constantly select andgraze the lucerne plants, thusreducing their vigour.

Sheep have been success-fully grazed on farms at Morawaand Mingenew on a three-pad-dock system for three-weeks-onand six-weeks-off (see Morawacase study at the end of this sec-tion). Other farmers with onlyone paddock of lucerne haveused two to four times the nor-mal stocking rates for one tothree weeks at a time. The mainissue is to rest the lucerne fromthe intensive grazing becausesheep will selectively graze thelucerne plants due to their highdigestibility and palatability.

0

200

400

600

800

1000

1200

1400

1600

1-Jan 26-Feb 23-Apr 18-Jun 13-Aug 8-Oct 3-Dec

Date

FEEDAVAILABLEKG/HA

Reliable GrowthVariable Growth2 Week Grazing

Figure 2. Predicted feed availability profile for an established stand of lucerne in the 350

to 400 mm annual rainfall zone.


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Sheep growth ratesGrowth rates of more than

one kilogram per week can beexpected from sheep grazing ondryland lucerne. Growth rates of1.13 to 1.75 kilograms per headper week have been measured atthree wheatbelt sites in WesternAustralia (Table 2). The sites allhad a three-paddock system.Stocking rates have been aver-aged over the three paddocks.

Thirty-four 12-month-oldMerino wethers were used atthe Morawa Lucerne ResearchSite (see the following casestudy) where they were grazedon a rotational basis in athree-paddock system (threeweeks on, six weeks off). Theywere grazing from 2 June 1999

until 15 January 2000 at an aver-age stocking rate of almost sixhead per hectare over the entiresite (17 per hectare for threeweeks at a time). However, theirweight was only measured from7 September (after they wereshorn) to 30 November. Agrowth rate of 161 grams perhead per day (1.13 kilogramsper week) was measured forthe period.

On a farm near Mingenew,the same rotation produced a

growth rate for one-year-oldmixed sex Merinos of 204 gramsper head per day (1.43 kilogramsper week) measured from July toSeptember 2000. At a third sitenear Dandaragan, 12-month-old Awassi ram lambs weregrazed on lucerne from 11 to 29

February 2000, and a growthrate of 250 grams per head perday (1.75 kilograms per week)was measured for this period.

Economic value of lucerneA high value animal feed

such as lucerne should bematched to a high value grazingenterprise such as prime lambproduction. The green feed fromlucerne can be saved, by de-stocking for extended periodswhile the lucerne dry matterincreases, until the early sum-mer period (October/December),late autumn (April/May) orwhenever considerable summerrain is received.

Landcare considerationsLucerne is a herbaceous

perennial plant that develops adeep root system and has agreater ability to dry out the soilprofile than an annual crop orpasture species. For this reason

lucerne is being evaluated as anoption for farmers as a part of a“low recharge farming system”that will help to reduce rechargeto water tables and the subse-quent development of sec-ondary salinity.

It is expected that the areaof lucerne currently beinggrown in Western Australia willincrease over the next fiveto ten years. AGWEST lucerneresearchers Roy Latta and KeithDevenish have estimated thatalmost 400 farmers seededlucerne in 2000, many for thefirst time. The indication is thatthe area established to drylandlucerne in Western Australia is atleast 50, 000 hectares and couldbe as high as 75, 000 hectares.The increase in the area of lucernehas grown at about 50 per centeach year since 1995, when therewere only 5000 hectares estab-lished to lucerne.

Other specialconsiderations ó Bloat in sheep grazing dry-

land lucerne stands inWestern Australia has notbeen commonly reported(see section on animalhealth); it is mostly associ-ated with cattle.

ó Enterotoxaemia (PulpyKidney) may cause animallosses on dryland lucerne asis the case on many otherhigh quality feeds or grainsupplements. Cattle andsheep should be vaccinatedagainst enterotoxaemia.

ó Red gut and nitrate poison-ing are minor problems thatmay occur on lucerne, butthey have not caused signifi-cant problems on drylandlucerne in Western Australia.

Table 2. Sheep growth rates on dryland lucerne at three sites in the wheatbelt using athree-paddock system

Location Grazing Stocking Initial Final Grazing Weight Weekly period rate weight weight days gain growth

(hd/ha) (kg) (kg) (kg/hd) (kg)

Morawa Sep-Nov’99 6 45.5 59.0 84 13.5 1.13

Mingenew Jul-Sep’00 10 45.0 58.5 66 13.5 1.43

Dandaragan Feb’00 12 - - 18 4.5 1.75


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Further readingDevenish, K.L.; Rogers E.S. andRogers, D.A. (2000).Agriculture WA,“Trial andDemo Reports 2000”,Northern Agricultural Region”,pp 195 – 196.

Farmnote No.4/98. Drylandlucerne – establishment andmanagement.

Stanley, M. and Christinat, R.(1994). “Success with drylandlucerne”, 1.2-6. Printed by OpenBook Publishers, Adelaide.

ó Lucerne provided an extrathree months of green sheepfeed after the end of spring.

ó Sheep gained weight at 1.13

kilograms per week betweenSeptember and November.

ó An opportunity exists to fin-ish prime lambs on lucernefor the December/Januarymarket.

Site details

A lucerne trial was estab-lished at the Morawa Agric-ultural College in 1998 to evalu-ate the potential of lucerne inthe low rainfall region of thenorthern wheatbelt. PioneerL69 lucerne was sown on 2 Juneat five kilograms per hectare.During the first 12 months thelucerne was crash grazed forshort periods in October,December, March and April. Thesix-hectare area was then fencedinto three, two-hectare plots.

Grazing details

Thirty-four Merino wetherhoggets (12 months old) weregrazed on the site during thesecond year from 2 June 1999 to15 January 2000 on a rotationalsystem of three-weeks-on andsix-weeks-off. The stocking rateduring the grazing period was17 sheep per hectare, producingan average stocking rate overthe entire site of almost sixsheep per hectare.

The sheep were shorn inSeptember and then weighedevery three weeks until 30

November. However, the sitewas grazed until 15 January. A

significant fall of rain (37 mil-limetres) was received at theend of January 2000 so thesheep were grazed on thelucerne again for four weeksin February. More rain wasreceived in March (79 millime-tres) and the plots were ready forgrazing by the beginning ofApril. The summer of 1999/2000

was abnormally wet and so in amore normal summer the avail-ability of feed would be lower.

Results

The average liveweight aftershearing was 43 kilograms, con-dition score 2.9. By 30 Novemberthe average weight hadincreased to 59 kilograms andthe condition score to 4.6 (thisis an exceptionally high condi-tion score and suggests thatthe stocking rate was too low).The growth rate during thisperiod was 161 grams per day(1.13 kilograms per week). Theannual species component ofthe pasture had senesced byearly September.

Conclusions

This was one of the first tri-als of sheep grazing lucerneto be conducted in WesternAustralia. The results indicatethat lucerne can provide greenfeed for several weeks longerthan annual pastures in latespring/early summer. They alsoindicate that farmers can expectsheep to grow at a minimum ofone kilogram per head per weekwhile grazing lucerne.

Merino wether hoggets grazinglucerne at the Morawa AgriculturalCollege in March.

CASE STUDY - MORAWA DRYLAND LUCERNE TRIAL Keith Devenish, Department of Agriculture, Northam


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K E Y M E S S AG E Só Tagasaste grows well on deep poor sands where annual crops and pastures struggle.ó Tagasaste is only of moderate quality in autumn and animals need lupin supplements

during this time to grow.ó Tagasaste can be set stocked with cattle, but only grazed for up to six weeks at a

time with sheep.

Soil types for tagasasteTagasaste grows best on

freely drained, deep soils suchas sands and deep gravels.Tagasaste is well suited to thepoor deep sands of WesternAustralia. It will not do well onshallow soils or where there iswaterlogging.

Soil acidityTagasaste grows best on

soils with a pH between 4 and 7.

Salt and waterloggingtolerance

Tagasaste has a nil toleranceof salt or waterlogged conditions.

Rainfall zonesTagasaste grows success-

fully in areas of 300 to 1000 mil-limetres of annual rainfall.

Cost of establishmentIt costs about 100 dollars per

hectare to establish tagasaste.This cost varies dependingon plant and row spacing,and the insect and vermin con-trol required. There are often

following spring. Floweringresults in the leaves beingdropped, a slowing of plantgrowth and a decline inpalatability over the follow-ing summer.

ó Tagasaste requires mechani-cal cutting if it is allowedto get beyond the reach ofthe animals grazing it(sheep can only graze up toabout 1.2 metres). Cuttingwill cost about 40 dollarsper hectare provided it iscut soon after reaching itspermissible height.

ó Tagasaste can be grazedat any time of the year.However, the feed quality isbest in winter and poorestin autumn.

Feed availabilityIn the West Midlands,

tagasaste can produce betweenthree and five tonnes of dry mat-ter per hectare per year. Highestproduction will be achievedwith good rates of superphos-phate (200 to 300 kilogramsper hectare per year) and onsites with perched watertables.

additional costs for re-fencingpaddocks and providing newwater points.

Grazing managementó Tagasaste should be only

lightly grazed during the firsttwo years. Once mature,tagasaste performs best withwell managed, hard grazing.

ó Tagasaste can be completelystripped of all leaves byintensive grazing with sheepas long as it is then allowedto recover.

ó While tagasaste can beheavily grazed by sheep forup to six weeks withoutcausing damage, it shouldnot be set stocked by sheepfor extended periods as theydamage the new shoot budsand can kill plants.

ó Cattle can continuouslygraze tagasaste becauseunlike sheep, they do notremove the new shoot buds.

ó Tagasaste must be hardgrazed and/or cut at leastonce in the first six months ofeach year. This prevents theplant flowering during the

Tim Wiley, Department of Agriculture, Jurien Bay

Tagasaste (Fodder Shrub)

Very good production can beachieved in low rainfall areaswhen tagasaste is situatedabove sandplain seeps.

While tagasaste is a trueperennial and grows year round,there is a distinct seasonal pat-tern of growth and feed quality.Tagasaste growth peaks inspring and is lowest at the endof autumn. Tagasaste respondsquickly to summer and autumnrain. Cold weather and frostslow tagasaste growth in winter.

Feed qualityFertiliser trials have consis-

tently shown that high ratesof phosphorus fertiliser arerequired for maximum animalgrowth rates. At the DunmarResearch Station, Badgingarra,an extra kilogram of liveweightper hectare was gained fromcattle with every extra kilogramof superphosphate per hectareapplied (up to 300 kilogramsper hectare). At this site thetagasaste feed production peak-ed with less than 200 kilogramsper hectare per year of super-phosphate. Animal productionimproved with even higher ratesof fertiliser (Figure 1).

This occurs because phos-phorus fertiliser improves thefeed quality of the tagasasteresulting in an increased feed

intake by the animals. Similarresults were seen at this sitewhen sheep grazed the trial.While growth rates of bothsheep and cattle were minimalin autumn, the higher rates ofsuperphosphate meant that ani-mals were still gaining weightslowly rather than losing weight.

In tagasaste, protein,digestibility and most mineralsare highest in winter and springand then gradually decline oversummer. During winter andspring, tagasaste is of very goodquality and animal growth ratesare as good as on any othergreen feed. No supplements arerequired at this time of year.

Over summer and autumnthe feed quality graduallydeclines.By late autumn animalson tagasaste will only be main-taining condition. At this timeof year protein is the limiting fac-tor for animals despite it neverdropping below 14 per centin the tagasaste leaf. Phenoliccompounds are thought toinhibit animal intake andgrowth rates in autumn.

Trials and farmer demon-strations have shown that sup-plements with a good proteinsource (such as lupins) will boostanimal growth rates in autumn.

Supplementation of stock graz-ing tagasaste with lupins pro-duces a very efficient feed con-version ratio of 4 to 1. That is,one kilogram of liveweight gainis achieved for each four kilo-grams of lupins fed.

In autumn, mineral concen-tration in the edible fraction oftagasaste can drop below levelsconsidered necessary for graz-ing animals. If animals arerequired to make growth inautumn, supply a well-balancedsalt-based mineral lick.

Occasionally tagasaste willnot be palatable to sheep inautumn. Reasons for the vari-ability between paddocks andseasons are not clear. However, ithas been found that palatabilityis improved if tagasaste is cutmechanically and left to dry forseveral days.

Out of season prime lambsIn a 1997 experiment at

Dunmar Research Station,Merino ewes that lambed inMarch (Merino x Polled Dorsetlambs) were grazed ontagasaste in the short ‘broccoli’form until late July withoutsupplementary feeding. Thelambs grew at 228 grams perhead per day during that period


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LIVEWEIGHTGAINKG/HA

-50

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300

350

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0 30 60 80 160 240 400

Superphosphate kg/ha/year x 5 years

SUPERPHOSPHATE INCREASES CATTLEPRODUCTION FROM TAGASASTE

SpringWinterSummerAutumn

Mature flowering tagasaste on deepsands near Goomalling.

Figure 1: Liveweight gains of cattle grazing tagasaste grown with increasing rates ofsuperphosphate on new land at Dunmar.


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while still on their mothers.(This rate of liveweight gain issimilar to those on annualpasture). In a similar experi-ment where the lambs weredropped in December theygained only 100 grams per headper day to July.

Returns from tagasasteTrials conducted for the

Martindale Research Project,found that 100 sheep could befed for 30 to 40 days on tagasastethat had been locked up for11 months. This was equivalentto a year round average of eightto ten DSE per hectare per year.This is a considerable improve-ment for these poor sandy soilsthat previously carried only oneto two DSE per hectare per yearwith annual pastures.

However, in the trialsdetailed above, the sheep graz-ing tagasaste usually only main-tained weight in autumn.Lupins are required to enablesheep to grow out at this time ofyear. One kilogram of lupinsshould result in 0.25 kilogramsof liveweight gain. Therefore, iflupins are costed at 200 dollarsper tonne, then an extra kilo-gram of liveweight gain can beachieved at a cost of 80 cents.

If tagasaste is grazed inwinter or spring, no supple-ments are required to grow ani-

mals out. Growth rates of ani-mals on tagasaste in winter andspring are similar to those ongood annual pasture. This wasseen in trials at the BadgingarraResearch Station even whenall the inter-row pasture wassprayed out and the animalsonly had tagasaste.

A whole farm analysisbased on performances on theDunmar Research Station hasshown that tagasaste is prof-itable when it is used to replacesupplementary feeding of sheepwith grain in autumn. Theanalysis was done on a self-replacing Merino flock. In theanalysis, the whole farm prof-itability was very sensitive towool price. However, at any woolprice it was profitable to haveten per cent of the farm sown totagasaste to replace the needfor supplementary feeding (seeFigure 2).

SpeciesTagasaste is a cross-polli-

nating species and the seed istherefore a genetic mix. Thereare no true commercial ‘vari-eties’ of tagasaste.

Landcare benefitsOn deep soils (ten metres)

tagasaste can use all the sea-son’s rainfall, thereby loweringwater tables. Where tagasastecan tap into a perched, freshwatertable it can use twice theaverage rainfall.

Further readingAngell, K. and Glencross,R. (1993). Tagasaste andAcacia saligna establishmentusing bare-rooted seedlings.Department of Agriculture,Bulletin No. 4262.

Lefroy, E. C.; Oldham, C.M. andCosta, N.J. (1997). TagasasteChamaecytisus proliferus.Proceedings of a workshop toreview tagasaste research inWestern Australia. Centre forLegumes in MediterraneanAgriculture (CLIMA). OccasionalPublication No. 19, CLIMA,Western Australia.

Wiley, T.; Oldham, C.; Allen, G.and Wiese, T. (1994). Tagasaste.Department of Agriculture,Bulletin No. 4291.

% of the arable area of the farm established to tagasaste

NETTCASH($)

-100000

-75000

-50000

-25000

0

25000

50000

75000

100000

125000

150000

0 10 30 65

Figure 2: A comparison of the analysis of the MIDAS model output comparing the netcash returns from farms with zero, 10%, 30% or 65% of their arable area as tagasaste in1989 ö and 1991 ˚ at a wool price of 935 cents per clean kg. The analysis in 1991 alsoincluded the influence of a range in the price of wool, 406 cents ö, 582 cents ˚, 759

cents ó and 935 cents ˚ per clean kg. The major assumptions in the 1991 analysis were,tagasaste ration grazed = 6000 sgd/ha in autumn, tagasaste grazed 7 days per week inall other situations = 3000 sgd/ha, no cropping and net cash ($) does not include intereston the investment in tagasaste

Tagasaste cutter.

K E Y M E S S AG E Só In the south west of Western Australia, there are over 100 native grass species,

most of which are perennial.ó Little is known about the agricultural suitability and performance of most of

these grasses.ó The summer-active native species in particular could be useful components of

permanent or long rotation pastures.ó From limited information, it seems that moderate growth rates, of 100 to 200

grams per head per day, could be expected of crossbred sucker lambs on native-grass dominant pastures.

Roy Butler, Department of Agriculture, Merredin

Native Perennial Grasses inPermanent Pastures

There has been a resur-gence of interest in perennialplants suitable for permanentor long-rotation pastures. Theperennials that are particu-

larly desirable are those thatwill grow in summer, reducingrecharge and possibly lower-ing water tables. For sheep,summer-active perennialssupply green, nutritious feedwhen most annual pastureplants are dead and of lownutritional value. Summer-active perennials can fill orpart-fill the summer-autumnfeed gap, thus reducing sup-plementary feed costs. If thereis sufficient summer rain orsuitable ground water, stockmight be finished for salesolely on pastures containingsummer-active perennials.

To date, the perennialplants attracting most interestfor use in pastures are intro-


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Curly windmill grass (Enteropogan acicu-laris) at Merredin in April.

duced species. These are com-prehensively covered in the pub-lication “Perennial grasses foranimal production in the highrainfall areas of WesternAustralia” (see ‘further reading’section for details) and so arenot covered by this reference.However, some native perennialgrasses are also worthy of con-sideration and so provide thefocus of this chapter. They areadapted to our climate and ourgenerally poor soils, and someappear to be both palatable toand safe for stock. However,these are early days in the studyof our native grasses, and in par-ticular their possible agricul-tural benefits.

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Feed qualityThe following table shows

the analyses for feed quality ofthree species of native perennialgrasses that are summer-activeand growing on farms in theeastern wheatbelt. These partic-ular grasses can be quite palat-able and nutritious, dependingon plant maturity and soil condi-tions. The samples were collec-ted in summer when the plantswere probably nutritionally attheir best, that is, leafy, green,and growing vigorously.

How well will lambs growon pastures containing nativegrass species? This depends onthe plant species, density andstage of growth, and soil condi-tions, as well as animal andpasture management. The fol-lowing case study suggests thatlambs will probably grow atmoderate rates (100 to 200

grams per head per day), espe-cially if there is above averagesummer rain. Supplementationwill be necessary in dry sum-mers, and if higher growth ratesare required.

Case study - Crossbredlamb production onnative perennial grassbased pasture.

Roy and Judith Butler runa small crossbred flock ona farm near Merredin. Thepermanent pasture is domi-nated in summer by nativeperennial grass species, espe-cially windmill grass (Chloristruncata) and curly windmillgrass (Enteropogon acicularis),with some leafy nine-awn(Enneapogon polyphyllus). Thesheep are run as one mob, witha ram, throughout the year.

As with other perennialpasture species, careful man-agement of native grasses isessential, especially in summerand autumn. Rotational grazingis practised with rest periods toallow seed set and recovery fromdefoliation.

The summer of 1999/2000

was one of the wettest everexperienced in the district. Thegrowth of windmill grass, in par-ticular, was exceptional. Thestocking rate over the summer

was approximately 2.8 DSE perhectare. In early February, thetotal food on offer (FOO) was2300 kilograms dry matter perhectare and the green FOO was1300 kilograms dry matter perhectare. Over summer, thesheep received a small lupinsupplement of approximately 30 grams per head per day.

The autumn and winter of2000 were also unusual, with alate break and a poor germina-tion and subsequent growth ofannual grasses and legumes.Windmill grass and curly wind-mill grass continued to growthrough the winter, althoughthey are regarded as summer-active species. Two winter-activenative perennial species – aspear grass (Austrostipa species)and a wire grass (Aristidaspecies) – became prominent inthe pasture during the winter.The sheep were supplementedwith an average of 64 gramsper head per day of lupins fromApril to the end of July, whensupplementary feeding ended.The stocking rate climbedsteadily through the winter toa peak, in early Septemberat approximately 4.3 DSE perhectare.

Figure 1 shows the moder-ate, average monthly growthrates of sucker lambs born in1999 and 2000.

A mixed sward of native perennial pastures at Merredin in April.

Further ReadingMiscellaneous Publication 2/98.Greathead K.; Sanford P. andCransberg L. (1998). Perennialgrasses for animal productionin high rainfall areas of WesternAustralia. Department ofAgriculture.

Miscellaneous Publication 8/99.The use of native perennialgrasses on farms in the wheat-belt of Western Australia.Department of Agriculture.


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Table 1. Feed quality of some summer-active native perennial grasses, sampled inJanuary/February 2000

1999 drop lambs2000 drop lambs

Oct

Nov De

c

Jan

Feb

Mar Ap

r

May Jun Jul

Aug

Sep

Oct

Nov De

cAVERAGELIVEWEIGHTGAIN(G/HEAD/DAY)

0

50

100

150

200

250

300

350

Figure 1. Average monthly growth rates of crossbred sucker lambs on predominantlynative grass pasture, Merredin (1999/2000).

1 From ungrazed, continuously cropped, fertilised, no-till paddock.2 From intermittently grazed, unfertilised paddock, in continuous pasture since 1994.

Curly Windmill Windmill Leafywindmill grass grass

1grass

2nine-awn

Moisture (%) 29.8 73.8 60.2 74.5

Dry Matter as received (%) 70.2 26.2 39.8 25.5

Acid Detergent Fibre (%) 32.9 33.6 33.1 35.3

Dig. Dry Matter (%) 66.0 63.4 61.2 62.1

Est. Metabolisable Energy(MJ/kg DM ) 9.6 9.1 8.8 8.9

Crude Protein (%) 19.6 14.2 10.4 15.0

Native Grasses Information Kit.Produced by Avril Baxter for theRevegetation on Farms Project(May 2000). Sustainable RuralDevelopment Program,Department of Agriculture.

Western Australian NativeGrass Society Newsletter.Editor Dallas Lynch, GreeningAustralia (WA) Northam.

Farmnote 43/2001 Nativeperennial grass-based pasturesfor livestock.


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K E Y M E S S AG E Só There is a range of subtropical perennial grasses available for most soil types.ó Excellent production can be achieved where there is a shallow water table.ó With good management, animals can grow on perennial grass pastures over summer.

Soil typesSubtropical perennial gras-

ses will grow on almost all soiltypes. Differences within speciesare due mostly to their responseto soil moisture. It is recom-mended to sow a mixture ofspecies to cover any variations insoil type (see Table 1 for thebroad growing environments ofdifferent species).

In general, subtropicalperennial grasses should not besown on areas that are to beused for winter cropping as theymay be difficult to drill seedthrough and are expensive toremove. However, satisfactoryresults have been reported onthe south coast with canolasown into perennial grass. Ontwo farms where kikuyu grasswas sprayed before cropping, agood regeneration of the grassfollowed the canola crop, withthe slow-growing kikuyu grasshaving little effect on the canolacrop over the winter or on itssubsequent yield.

AcidityThere are no quantitative

data on the effects of soil pH onsubtropical perennial grasses in

Western Australia. Experiencesuggests that problems for sub-tropical perennials would onlybe encountered at the extremesof acidity or alkalinity. Soil pH islikely to be more of an issue forthe companion legumes.

Salt toleranceSpecies such as puccinellia,

tall wheat grass, Rhodes grassand para grass have good salttolerance, but establishment isdifficult on salt-affected areas.Exposing potentially salineareas in late spring by sprayingand grazing the areas in readi-ness for seeding with tropicalgrasses, can accelerate the sur-face accumulation of salt,adding to the difficulties ofestablishment.

ClimateSubtropical perennial gras-

ses are summer active andwinter dormant. All thesegrasses will be burnt by frost,but will survive.

The grasses will grow andsurvive in all regions of WesternAustralia. Their production ismore dependent on their posi-

tion in the landscape and thepattern of rainfall, than on theaverage annual rainfall. Thesepastures respond well to sum-mer rainfall events.

The seed of these grasseswill not germinate if it is toocold. The temperatures requiredfor germination will not beachieved until late September inthe northern section of the agri-cultural region and by early tomid October in the south of theagricultural region.

Cost of establishmentSubtropical perennial gras-

ses are difficult to establishand require total weed controlbefore sowing. They should besown in spring when tempera-tures are rising. The seed mustbe placed on the surface andthen pressed or rolled in.

Experienced farmers esti-mate that these grasses can beestablished for about 100 dol-lars per hectare. They also sug-gest that it is worth consideringwithholding grazing duringthe establishment phase. Thegrasses are safe to graze oncethe roots are well establishedand the plants cannot easily be


Subtropical Perennial Grasses

pulled from the ground. Failureto establish the grasses at thefirst attempt will increase over-all costs considerably.

Grazing managementRotational grazing is prob-

ably the best way to managethe perennial grasses over sum-mer. However, most species willpersist under set stocking.Whatever the grazing method,grazing pressure needs to bemaintained on these grassesover summer and throughautumn because if they areunder-grazed at this timethey will deteriorate in qualityand palatability.

On the highly productivewet areas, farmers are usingtemporary electric fences to cell-graze these pastures. They maygraze the grasses at up to 1000

DSE per hectare in a cell for up toa week. Generally the rotation isset up so that there is a four tosix-week rest between grazings.However,on the south coast,con-tinuous grazing of kikuyu grassover summer at high stockingrates has proved to be successful.

Subtropical perennial gras-ses should be grazed down hardto ground level by the end ofautumn. This allows the annuallegumes in the pasture to makegood growth at the break of sea-son. With a well-managed pas-ture mix, it should be difficult tosee perennial grasses below theclovers in winter and spring.Winter grazing should aim tooptimise the annual legumecomponent of the pasture.

Feed availabilityThe amounts of feed pro-

duced by subtropical perennialgrasses depends on the supply ofnitrogen and soil moisture (seeTables 2 and 3).


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Soil moisture Dry Winter wet Winter flooded Salt toleranceSpeciesRhodes grass # # #Green panic #Setaria # ## #Blue panic ## #Elephant grass # ##Kikuyu # ## ##

(in southern areas only)

Para grass ### #Paspalum ## ##Tall wheatgrass ## # #Puccinellia ## # ##

Table 1. Subtropical perennial grass species and their use in the landscape

Key # satisfactory to ### very satisfactory

*Broad leaf biennial herb of high feed value

Valley planting of tall wheat grassnear Williams.

These grasses are verydrought tolerant and can survivewithout summer rain. On siteswith shallow perched waterta-bles (less than 2.5 metres) theydo not require summer rain to bevery productive.

Perennial grasses have ahigh requirement for nitrogenfor optimum production. Wherethere is adequate soil moisturethey will respond to up to 400

kilograms per hectare of nitro-gen. If bagged nitrogen fertiliseris applied it should be throughsplit applications while soil mois-ture persists. However, the mostefficient system for meetingnitrogen requirements is to havea productive companion legume.

Species Dry Matter DM Crude Metabolisable Pasture (10 Nov- digestibility protein energy growth

13 Feb 96) rate(t/ha) (%) (%) (MJ/kg) (kg/ha/day)

‘Nandi’ Setaria 5.0 71 9.1 10.2 53

‘Kazungula’ Setaria 12.1 64 8.0 9.0 127

Green Panic 11.1 64 6.1 9.0 117

Kikuyu 5.7 - - - 60

Hymenachne 8.4 71 8.3 10.0 88

‘Gatton’ panic 8.8 63 8.4 8.9 93

‘Puna’ chicory* 4.3 85 12.1 12.3 45

‘Callide’ Rhodes grass 7.0 68 11.1 9.7 74

Table 2. Perennial grass production and quality on a winter flooded white sand atCataby (13 February 1996)


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Feed qualityThe quality of feed provided

by subtropical perennial grassesdepends on the availabilityof moisture, the time of year(Figure 1), the amount of nitro-gen available, stage of regrowth(Figure 2) and the grazing pres-sure on the grasses.

There is a general trendfor the quality of feed prov-ided by perennial grasses todecline gradually over sum-mer. Rotational grazing willprovide a pasture with a largeproportion of young leaves withhigh nutritional value. AtBadgingarra, the sheep gainedweight even though the analy-sis of the whole plant showedthat it was of very low feed qual-ity. In this case, the sheep selec-tively grazed the young grassshoots and these were of higherquality than the rank parts ofthe grasses.

Both protein and energycan become limiting. Animalsshould be monitored and a sup-plement such as lupins fed asrequired. Companion legumeswill also boost the quality of thetotal feed supply when they aregreen. On wet areas balansa orpersian clover, Cadiz serradella,and strawberry or white clover

are likely to be suitable for grow-ing with the perennial grasses.On drier areas, serradellas, sub-clover,arrowleaf clover,biserrulaor blue lupins may suit depend-ing on the location.

Grazing performancesfrom subtropicalperennial grasses

Stocking rates for subtropi-cal perennial grasses vary fromsite to site depending on theavailability of subsoil moistureand summer rain.

The following examplesoutline the sheep carryingcapacities of some of thesegrasses.However,presently thereis little documentation of animalperformance on these subtropi-cal grasses in the agriculturalareas of Western Australia.

David Monks at Badgingarraruns 1800 weaners on30 hectares of kikuyu grass andstrawberry clover on a low lyingwet sand throughout each

Table 3. Perennial grass production and quality on a valley loam at Moora (13 February 1996)

Species Dry Matter DM Crude Metabolisable Pasture (26 Oct- digestibility protein energy growth

13 Feb 96) rate(t/ha) (%) (%) (MJ/kg) (kg/ha/day)

‘Katambora’ Rhodes 3.8 69 8.2 9.9 35

grass‘Pioneer’ Rhodes grass 3.2 70 9.2 9.9 29

‘Callide’ Rhodes grass 3.1 73 10.7 10.5 28

‘Nandi’ Setaria 3.4 80 15.3 11.5 31

‘Kazungula’ Setaria 4.8 79 13.2 11.4 44

Guinea grass 4.0 76 13.4 10.9 36

‘Green’ panic 5.3 77 13.4 11.1 48

‘Gatton’ panic 3.4 79 13.7 11.3 31

Kikuyu 2.5 78 16.7 10.2 23

18

.11

.93

3.1

2.9

3

8.1

2.9

3

20

.12

.93

30

.12

.93

10

.1.9

4

24

.1.9

4

14

.2.9

4

SETARIA CRUDE PROTEIN (%)AND METABOLISABLE ENERGY (MJ/KG)

MEProtein

0

1

2

3

4

5

6

7

8

9

Figure 1: Decline in crude protein content of Setaria over summer on a poor sand(Badgingarra 1993/4).

SETARIA CRUDE PROTEIN (%)AND METABOLISABLE ENERGY (MJ/KG)

MEProtein

1

2

3

4

5

6

7

8

9

0

35 46 56 68 200

Days regrowth since hard grazing

Figure 2: The quality of Setaria declines as the plants regrow from hard grazing(Badgingarra 1993/4).

summer. He uses a cell grazingsystem to rotate sheep andavoid Barbers Pole worm prob-lems. These sheep do not see dryfeed until they are one year old.In other words, it is not untilthey are in their second summerthat they go on to dry annualpastures for the first time.

On a neighbouring farm,Dale Park ran seven weaners perhectare for 114 days over sum-mer on Setaria grass. He com-pared liveweights on Setariawith a district practice of graz-ing Blue lupins and oat stubbles(Figure 3). This was a deep, poorwhite sand and there was nosummer rain. Weaners on theSetaria gained 30 grams perhead per day without supple-mentary feeding.

At Peter Nixon’s, WestGillingarra, weaners were run at265 per hectare for 30 days on astrawberry and balansa pastureon wet sand over summer. Theseweaners put on 150 grams perhead per day or 1100 kilogramsof liveweight per hectare.

An experiment at Many-peaks on the south coastshowed the benefits of grazingkikuyu grass-based pasturescompared with annual pastures.The main benefits were in carry-ing capacity (that is, increasedstocking rate and/or less supple-ments fed) and in wool quality,with stronger cleaner woolgrown on the kikuyu grass.

Other considerationsBarbers pole worm can be a

serious problem on wet areaswith perennial pastures, andother worm species may be aproblem in the milder climates.To help reduce this problem, thepastures should have a longspell before summer grazing.

Sheep should be ade-quately drenched before grazingthese grasses. Long spells (forexample, six weeks) betweengrazings in summer, will,through heat and desiccation,help reduce viable worm eggsavailable on the pasture. Wherethere is concern, regular sam-pling and assessment of theworm status of sheep should beundertaken and further advicesought from a veterinarian.

In some areas there havebeen some problems with sele-nium and cobalt deficiencies onthe wet sands over summer.Farmers should apply these traceelements with fertiliser ordirectly to the animals (seeFarmnote 110/94,‘Trace elementdeficiencies in sheep and cattle’).

Horses should not be grazedon pure Setaria pastures as theycan develop the ‘Big Head’ syn-drome caused by a calciumimbalance due to high levels ofoxalates in Setaria.

Problems with oxalates inother species of animals havebeen reported in the easternstates but not in WesternAustralia.These types of problemsare usually avoided where there isa mixture of pasture species.

Landcare benefitsThe subtropical perennial

grasses will increase water useand prevent both wind andwater erosion.

Further readingMiscellaneous Publication 2/98.Greathead K.; Sanford P. andCransberg L. (1998). Perennialgrasses for animal productionin high rainfall areas of WesternAustralia. Department ofAgriculture.

Farmnote 20/99. Perennialgrasses : their role in the EllenBrook Catchment

Farmnote 11/95. Kikuyu, theforgotten pasture

Farmnote 110/94.Trace element deficiencies insheep and cattle

Farmnote 8/92. Chemicalmanipulation for irrigatedkikuyu grasses.


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Rhodes grass on waterlogged flats nearBadgingarra in March.

SetariaBlueLupins& OatStubble

0 22 43 67 98

Days

23

24

25

26

27

28

29

30

Figure 3: Liveweight (kg) of weaner rams grazing Setaria or Blue lupins and oat stubblefrom 8 December 1993 to 31 March 1994 (Badgingarra).


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K E Y M E S S AG E Só Summer fodder crops are a viable feed source on wet areas and in wet summers.ó Soil temperatures must reach 14 to 19°C for germination, depending on species.ó There are some possible health problems with sheep grazing sorghum.


Summer Fodder Crops

Soil types/nichesSummer fodder crops will

grow:ó On most soils provided there

is a reasonable level of nutri-ents and soil moisture.

ó In areas where winter cropshave failed from water-logging.

ó In permanently wet areas.ó After good summer rains.

Soil pHThe suitable range for pH of

the soil is between 4.5 and 7.

Salt toleranceThe tolerance to salt in the

soil is moderate to poor depend-ing on the species of the crop.

Cost of establishmentIt costs about 80 to 150

dollars per hectare to growfodder crops.

Types of summerfodder cropsSorghum

Sorghums are summergrowing grasses with a reason-able drought tolerance. Thereare forage and grain varieties ofsorghum.There is also a range ofhybrids derived from crossingsorghum with sudan grass.However, only the forage typesof sorghum and their hybridsshould be used for grazing, asthey are more productive and ofbetter quality.

Sorghums usually producea greater bulk of summer feedthan other summer fodder crops.

Sorghums contain prussicacid that can be toxic to stock.Therefore, newer varieties havebeen bred with lower levels ofprussic acid.

Sorghums are usually bien-nial. This means that theybecome dormant over winterand regrow in the second sum-mer, after which they usually dieout. Varieties that show promisein Western Australia include‘Jumbo’ and ‘Superdan’.

Sorghums will not germi-nate well until soil tempera-tures reach 18°C at 9.00 a.m.Some germination occurs atlower temperatures, but theresulting seedlings are weakand do not perform well.

Pivot irrigated hybrid sorghum (SpeedFeed™) at Pingaring in February.


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Sweet sorghums

Sweet sorghums havehigher sugar levels than theother sorghums and this makesthem more suitable for silage.They also have coarser stemsthan the other sorghums andare, therefore, less suitable forgrazing by sheep.

Temperate millet

As a fodder crop, millets aresuited to one summer season. Insome cases millet has regener-ated from self-sown seed. Theseed is much less temperaturesensitive than sorghums andwill germinate at a 9.00 a.m. soiltemperature of only 14°C. (Seefurther discussion about soiltemperatures and germinationunder the heading ‘Other issues’

in this section). Millets do notcontain prussic acid but areusually not as productive assorghums or pennisetums.Varieties showing promise inWestern Australia include‘Shirohie’ and ‘Japanese’.

Forage pennisetums

Forage pennisetums werepreviously known as pearl mil-lets. Forage pennisetums gener-ally have higher protein anddigestibility than sorghums. Thepennisetums do not containprussic acid. They also have finerstems and are the preferredsummer forage for sheep.

Pennisetums are frost sen-sitive and can be killed if sowntoo early. Pennisetums requiresome rain after seedlings

emerge to promote the develop-ment of the secondary root sys-tem. They will germinate at16°C. A variety showing promisein Western Australia is‘Nutrifeed’.

Maize

Maize is extremely produc-tive, but is probably onlyviable in Western Australiawith irrigation.

Production potentialDry matter production of

summer fodder crops is depen-dent on the moisture supply.Yields of two to 10 tonnes drymatter per hectare could beexpected depending on mois-ture supply and nitrogen appli-cation. Because they usually relyon some summer rain, their pro-duction in Western Australiatends to be unreliable except onwet areas.

When considering the ben-efits of summer fodder crops itshould be remembered thatthey need to be fitted in withother management compo-nents for the whole farm.Wherecrops have failed from water-logging, summer crops are auseful option as they dry thesite out and also control weeds.Perennial pastures are a betteroption on permanently wetsites as there is a once only costof establishment.

Table 1. Average growth rates and condition scores of Merino and crossbred lambs onforage sorghum

Table 2. The nutritional value of sorghum before and after grazing

Initial Final Growth Conditionliveweight liveweight rates score

(kg) (kg) (g/h/d)

Crossbred 33.2 35.3 138 1.6

Merino 29.6 31.8 153 1.3

Overall growth rates 31.8 34.0 146 1.5

Stage of Dry Metabolisable Crude grazing matter energy protein(days) (%) (MJ/kg DM) (%)

1 80.7 10.2 22.1

15 54.9 9.8 18.6


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Case study - Sorghumover summer

Fiona Jones, Department ofAgriculture, Katanning

The performance of cross-bred and Merino lambs on BettaGraze forage sorghum was mon-itored at Beaufort River. A goodstand of sorghum was estab-lished which provided a valuablesource of feed over the summerperiod, particularly with thehigh summer rainfall causing arapid decline in dry feed quality.

The sorghum was seededin October in 75 centimetrerows and urea was spread at100 kilograms per hectarebefore the January rainfall.Application of urea can increasethe risk of prussic acid poison-ing on sorghum and needs to bemonitored closely. The lambswere stocked at 43 DSE perhectare for 15 days with sulphurblocks to reduce the risk of prus-sic acid poisoning.

The average liveweight gainfor the Merino and crossbredlambs was 146 grams per headper day with no supplementaryfeed provided during thisperiod. (See Table 1.)

The crude protein of thesorghum was high at the startof grazing (Table 2), when theplant had plenty of fresh leafmaterial. By the end of thegrazing period, the crude pro-tein of the sorghum was stillmore than adequate but themetabolisable energy waslower due to a higher propor-tion of fibrous stem and lessleaf material.

The sorghum was spelledfor three and half weeksbetween the first and secondgrazings. The plan was to grazethe sorghum three or four timesduring the summer. Used in thisway, sorghum provides a way toget lambs to a reasonableweight over summer before fin-ishing them in a feedlot.

Feed qualityThe quality of summer fod-

der crops will vary with soil mois-ture, soil fertility and grazingmanagement. Protein can varyfrom less than 10 to 25 per cent.Digestibility is normally in therange of 55 to 70 per cent.Proteinand digestibility both declinewith increasing age of a standover the summer and increasingheight of regrowth. Nitrogen fer-tiliser will improve the proteinlevel but not the digestibility ofsummer fodder crops.

While summer fodder cropscan provide feed of reasonablequality over summer, supple-ments with lupins may berequired for maximum growthrates of animals. Generally, morelupins will be required as thestand ages.

Summer fodder crops aregenerally low in both sodium(salt) and sulphur. Balancedmineral licks containing thesenutrients should be made avail-able to stock.

Grazing managementGrazing of fodder crops

should be delayed until theplants are well established. Forsorghums, do not put stock inuntil the crop is about onemetre high. Sweet sorghum canbe grazed when the crop is1.5 metres high and millet andpennisetums when the crop is0.5 metre. After this, the bestresults will be with rotationalgrazing, although set stocking isstill possible.

Do not graze the stand toolow. The sheep should beremoved once the height of theforage is down to 15 centime-

‘Jumbo’ sorghum growing on waterlogged flats at Dandargan in April.


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tres. Regular grazing helps delayflowering and this maintainsthe quality and growth rate ofthe fodder for a longer period. Ifthe fodder is left ungrazed, it ismore likely to suffer moisturestress. If sorghum plants areallowed to mature their proteinlevel and digestibility willdecline rapidly.

Grazing problemsPrussic acid poisoning

Animals can be affectedby prussic acid poisoningwhen grazing sorghums. Prussicacid is converted to hydrogencyanide in the gut of the animal.The cyanide reduces the uptakeof oxygen into the blood andsymptoms of the poisoninginclude muscle tremors, stag-gers, deep and rapid breathing,frothing at the mouth andgasping for breath. Death canoccur in extreme cases. In sheep,the poisoning can be treatedby drenching animals with14 grams of sodium thiosul-phate in 500 millilitres of water.

Factors that increase prus-sic acid levels are excess nitro-gen, inadequate phosphorusand moisture stress. The risk ofprussic acid poisoning can bereduced by ensuring that:ó sheep are not hungry when

first put on to sorghum;ó there is other feed in the

paddock;ó the sorghum is at least

0.8 metre tall;ó the plants are not grazed

when they are (moisture)stressed and;

ó a mineral lick containingsulphur is available.

Nitrate poisoning

Nitrate poisoning can occurin sheep grazed on a wide rangeof grass fodders. Fortunatelyit is not a common problem.However it will occur when thereare very high levels of soil or fer-tiliser nitrogen. The poisoningcauses severe gasping, convul-sions and death. It can be treatedby drenching with vinegar.

Other issuesSummer fodder crops will

not germinate at low soil tem-peratures. Ideal germination isachieved when the 9.00 a.m. soiltemperature at seeding depth is18°C. The millets will germinateat soil temperatures of only 16°C.Sowing too early will result inweak seedlings or the seed mayrot. This is different to the sum-mer active perennial pasturesthat can be sown up to a monthbefore the soils are warm enoughwithout any adverse effect. The9.00 a.m. soil temperature can beestimated as half way betweenthe daily minimum and maxi-mum temperatures.

Sow at two to five centime-tres depth where there has beengood weed control. Sow aboutfive kilograms per hectare ofseed at wide row spacings of0.5 to one metre. Close row spac-ing can lead to very poor results.

Use rates of fertiliser simi-lar to those used for wheatgrown on the same soil type.However, be careful where nitro-gen and potash are sown withthe seed as these fertilisers cankill emerging seedlings. It issafest to drill the fertiliser beforeseeding or with alternate runs

of the seeder. Use sulphate ofammonia if top dressing as ureais rapidly lost to the atmospherewhen spread in summer.

Landcare androtational benefits

The degree to which sum-mer crops help to dry out wetareas for the following seasonis not yet clear. Spraying outweeds in spring will reduce theirseed bank for the following year.This may well provide a meansof preparing for a winter crop,especially where weeds havebecome resistant to chemicals.However this will also reducethe legume seed bank that isimportant for subsequent pas-ture regeneration.

Further readingFry, J. (Compiled by) (1997).A reference manual for farmersinvolved in Woolpro productiv-ity evaluations.Segment 5 – Tactics for differentsummers, pp 15-18.Department of Agriculture.

Stuart, P.N. (1993).The forage book. Pacific Seeds,Toowoomba, Queensland.

C R O P SSheep performances on cereal and canola stubbles

Grazing sheep on grain legume stubbles

Grazing sheep on matured grain legume crops

Increasing lamb growth on medic pasture cover croppedwith sweet lupins


C R O P S

K E Y M E S S AG E Só Sheep can only consume a small proportion of the dry matter available in stubbles.ó Spilt grain is the most nutritious component of the diet of sheep grazing

cereal stubbles.ó Adult dry sheep can only maintain liveweight for a short period of time when

grazing dry stubbles alone.ó Young sheep will only maintain liveweight when spilt grain and green material are

also available.ó To minimise weight loss of adult sheep and maintain liveweight of young sheep,

supplementation of stubbles with cereal grain or lupin seed will be necessary.

Daniel Roberts, Department of Agriculture, Katanning andJanet Paterson, Sci Scribe Scientific Copywriting, Brookton.

Sheep Performance on Cerealand Canola Stubbles

IntroductionStubbles are a major feed

source for sheep during thesummer-autumn period inWestern Australia.

While there is often up tothree tonnes of dry plant mater-ial per hectare available, sheepgrazing stubbles eat only aboutsix per cent of it. Leaf material(59 per cent digestible) makesup about a quarter of the stub-ble material, while the stemmaterial (29 per cent digestible)accounts for just under half. Thelarge amount of indigestiblestem material reduces the over-all value of stubbles.

When grazing cereal stub-bles, the aim is to maintain theliveweight of young sheep, tominimise the weight loss ofadults and to maximise utilisa-tion of nutrients available fromstubbles. There are large lossesof edible material caused byshattering during harvest andtrampling as sheep selectivelygraze the stubble paddocks.Microbial breakdown and windalso contribute to the loss of thehigh quality components ofstubbles.

The energy content of thedry plant material determineshow much the stock can eat.About a quarter of fresh wheat

stubble has a digestibility ofmore than 55 per cent, one thirdhas a digestibility between 50 to55 per cent and the rest is indi-gestible stem material.

Young sheep (25 to 30 kilo-grams) will start to lose weightonce they are eating stubblematerial below 55 per centdigestibility which is thethreshold for maintenance ofliveweight.

C R O P S


Composition of stubblesLeaf material and spilt

grain provide the most nutri-tious components of the diet ofsheep grazing cereal andlegume stubbles. The averagenutritive values of stubblessampled in Western Australiaare recorded in Table 1.

The availability of smallamounts of green material(weeds or crop regrowth) follow-ing summer rains will alsoincrease the productivity of ani-mals that graze stubbles. Thesheep’s diet will consist of morethan 80 per cent green materialwhen there is as little as 40 kilo-grams per hectare of greenmaterial in the stubble.

Mature sheep grazed onstubbles may initially increasein liveweight because of inten-sive selection for these moredigestible parts of fresh stubbles(grain, weeds and leaf material).However, lighter or youngersheep are unlikely to maintainliveweight for as long, unlessconsiderable grain and/or ‘greenpick’ are available because theysimply cannot eat enough of thenutrients they need for growth.

Adult dry sheep (55 kilo-grams) grazed on crop residueswill only maintain theirliveweight for 60 to 100 sheep

grazing days per hectare. Youngsheep (25 to 30 kilograms)will not maintain liveweight ondry plant material alone andwill require supplementationwithin 7 to 14 days to avoidweight loss.

Supplementation is neededto maintain the weight ofyoung sheep on stubbles as wellas to improve the efficiencywith which nutrients within thestubble material are convertedto liveweight. The aim of sup-plementation is to stimulatethe sheep to eat more of thestubble by providing a protein-rich feed such as lupins.The pro-tein and soluble carbohydratein the lupins stimulate themicrobial population in therumen which can then processthe incoming stubble morequickly. It is important to usethe dry feed available in stub-bles before it is lost throughsummer rain and trampling.

Young sheep (25 to 30 kilo-grams) should be fed 50 to 75

grams of lupins per day fromthe first or second week on stub-bles. This should help toincrease their intake of higherquality stubble componentssuch as spilt grain and leafmaterial. However, the intake oflupins needs to be monitored toensure that the sheep are notsubstituting them for stubble.After week two, the lupin sup-plement will need to beincreased to 150 grams perhead per day because the moredigestible stubble componentswill usually have been eaten bythis time.

Table 1. The dry matter, energy, protein and fibre content (dry matter basis) of strawsand stubbles fed to sheep. The average across the range of values is shown in brackets.

Merino lambs grazing a barley stubble.Lambs grazing a barley stubble willrequire additional protein supplementsfor optimum growth.

These values were extracted from data collected by Independent Lab Services, Perth.

Straws/ Dry Metabolisable Crude Acid detergentstubble matter energy protein fibre

(%) (MJ/kg) (%) (%)

Oat 89 6.0 - 7.7 (6.8) 4.0 - 6.5 (5.0) 38.0 - 45.0 (43.0)

Barley 89 6.0 - 7.5 (6.7) 4.0 - 6.5 (5.0) 38.0 - 47.0 (44.0)

Wheat 91 5.8 - 7.0 (6.5) 2.5 - 6.5 (3.5) 43.0 - 52.0 (47.0)

Triticale 89 5.5 - 7.0 (6.3) 2.5 - 6.0 (3.5) 44.0 - 52.0 (48.0)

Lupin 92 5.5 - 9.5 (8.0) 6.0 - 10.0 (8.0) 36.0 - 44.0 (42.0)

Pea 90 6.5 - 7.8 (7.2) 6.0 - 8.5 (7.5) 38.0 - 44.0 (42.5)

Canola 92 5.5 - 7.5 (6.5) 4.0 - 7.5 (6.0) 42.0 - 50.0 (47.0)

Sorghum 88 5.5 - 7.0 (6.5) 3.5 - 6.0 (4.5) 45.0 - 54.0 (48.0)

Cereal stubblesThe spilt grain in cereal

stubbles contains starch thatcan cause acidosis if rapidly con-sumed. Acidosis is caused by thelowering of the pH in the rumenof sheep, leading to part of themicrobial population beingkilled off and a lessened abilityby the rumen to process fibrousfeed. To minimise the chances ofdeveloping acidosis, sheepshould be acclimatised to thegrain before being put ontoungrazed cereal stubbles.

Spilt cereal grain will notprovide enough protein forgrowing lambs and it is impor-tant to feed out some lupingrain as well. This will also helpthe sheep to better utilise cropresidues. If possible, lambsshould be moved regularly tonew stubbles so that they canhave maximum access to spiltgrain and leaf material. Anappropriate mineral mix shouldbe fed to overcome any possibledeficiencies of sodium, calcium,and sulphur.

After the removal of wean-ers, the stubbles can usually begrazed for a while by older sheep.

Canola stubblesObservations on the perfor-

mances of sheep indicate thatcanola stubbles do have somevalue as a stock feed but infor-mation collected so far is lim-ited. Any green pick arising afterswathing or from late maturingplants will increase the value ofthe stubble, particularly foryoung sheep. Liveweights ofyoung sheep on canola stubbleincreased by up to two kilo-grams over 12 days (the shortestperiod of weight gain) to 42 days(longest period of weight gain)on several farms located in thewheatbelt. Grazing time wasextended with an increase in theproportion of green or part-green canola stems in the stub-ble. Also of importance was theavailability of small greenbranches at the start of grazing.

Where there has been goodweed control, most canola stub-bles only have dry, hard and brit-tle stems. Sheep eat some of theresidual canola seed in theswathed rows but its influenceon their performance is notknown. Supplementation withgrain is usually required to main-

tain the liveweights of youngsheep grazed on canola stubbles.

Chaff Cart Heaps Recent developments in

cart collection systems haveimproved the availability of thehigher quality components ofcereal crop residues by separat-ing harvested material into leaf-rich and stem-rich components.The average nutritive valuesof the material in chaff-cartresidues in Western Australiaare shown in Table 2.

The heaps from the chaffcart collection system providean accessible source of feed forsheep at discrete locationswithin a paddock. The averageenergy content of the collectedmaterial is generally enough tomaintain the liveweight of adultdry sheep.

When cereal paddocks areharvested about half a tonneper hectare of chaff cart resi-dues is available for stock tograze while on the stubbles.Swathing the crop increasesboth the amount of materialcollected by chaff carts and thecapture of weed seeds.


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Table 2. The dry matter, energy, protein and fibre content (dry matter basis) of chaff-cart residues. The average across the range of various values is shown in brackets.

Merino lambs grazing a wheat stubble.Initially introducing lambs to the stubblefor short periods over several days isimportant for wheat stubble.

These values were extracted from data collected by Independent Lab Services, Perth

Chaff-cart Dry Metabolisable Crude Acid detergentresidues matter energy protein fibre

(%) (MJ/kg) (%) (%)

Oat 90 6.5 - 8.0 (7.2) 5.0 - 7.0 (6.0) 36.0 - 44.0 (41.0)

Barley 90 6.5 - 8.2 (7.5) 5.0 - 7.5 (6.5) 37.0 - 45.0 (42.0)

Wheat 90 6.2 - 8.5 (7.5) 4.5 - 8.0 (6.5) 39.0 - 50.0 (45.0)

Canola 92 6.0 - 8.5 (7.5) 5.0 - 9.5 (7.5) 42.0 - 50.0 (45.0)

Lupin 92 7.5 - 9.5 (8.5) 7.5 - 11.5 (9.5) 35.0 - 43.0 (41.0)


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There has been some moni-toring of sheep given access tothe harvested crop residue dur-ing summer on a limited num-ber of farms throughout thewheatbelt. The number of graz-ing days in paddocks with cartheaps was extended by up to31 per cent compared withthose stubble paddocks withoutchaff cart residues.

In large stubble paddocks,providing strategically locatedchaff heaps improves the utilisa-tion of the material availableover the whole stubble paddock.Sheep are attracted to grazethese chaff heaps particularlywhen they are located beyondthe over-grazed areas surround-ing a watering point.

Monitoring sheepperformance on stubbles

There is a wide variation inthe voluntary intake, ingestionof nutrients and performance ofsheep when grazed on dry cerealand lupin stubbles.

It is essential to weigh, or atleast condition-score, a sampleof 50 animals in a flock on amonthly basis to determinewhen the value of the stubblehas decreased and supplemen-tation is necessary for the main-tenance of liveweight.

Further ReadingAitchinson, E. (1988). Cerealstraw and stubble as sheepfeed. Journal of Agriculture,Western Australia. 29: 96-101.

Merino ewes on a canola stubble. Canola stubble has a low feed value unless there isgreen regrowth and may be better utilised by older animals.

Croker, K.P. and Suiter, R.J.(1977). Stocking rates forweaner sheep on standingcrops. Journal of Agriculture,Western Australia. 18: 21-23.

Jacob, R. (1984). Utilisation ofcereal stubble for sheep feed.In ‘How much wheat do sheepgrow’ (Western AustralianDepartment of Agriculture andNorth Midland Branch of theAustralian Society of AnimalProduction: Northam. WA).

Purser, D.B. (1983).The nutritional value of stub-bles. In ‘Stubble Utilisation’(Rural and Allied Industries:Perth. WA. pp 13-26).

Warren, B. (1991).Sheep performance on cerealstubbles. In ‘Stubble manage-ment in farming systems’(Technical Report No 40,Western AustralianDepartment of Agriculture.pp 44-52).

K E Y M E S S AG E Só Grain legume crop stubbles provide better quality sheep feed than cereal or canola

stubbles.ó The feed value of the stubble is directly related to the amount of seed left after

harvest.ó Sheep will preferentially select the seed first.ó Young sheep should be trained to recognise the seed.ó Sheep growth rates should be at least one kilogram per head per week.ó Sheep drink more water on a high protein feed.ó Grazing can be limited by the amount of ground cover available.

Keith Devenish, Department of Agriculture, Northam

Grazing Sheep on Grain LegumeStubbles

IntroductionCrop stubbles are the plant

residues left after harvest. Themajor components of the stub-bles of grain legumes in order oftheir feeding value to sheep areseed, leaf, pod, chaff and stemmaterial. Weed residues in pad-docks can also be of value assheep feed.

Contribution toliveweight

The feed value of legumestubbles is directly related to theamount of spilt seed left afterharvest. Therefore, the length ofgrazing depends on the avail-ability of the seed and whetheranimals need to gain or loseweight. Providing there are noother limiting restrictions to ani-mal performance, the legume

crop stubbles generally have thehighest summer feed value of allthe crop stubbles.

Constraints toliveweight gain

There are several factorsthat can limit animal perfor-mance when grazing grainlegume stubbles (see SheepHealth Issues). This sectionassumes the risk of the follow-ing problems are minimised:

ó Lupinosis is the main threaton lupin stubbles. Deathscan occur, but even low lev-els of the toxin that pro-duces lupinosis can limitweight gain.

ó ARGT - watch for annualryegrass toxicity if ryegrassplants are present in largenumbers.

ó Acidosis - grain engorgementgenerally has not been anissue, but theoretically couldoccur where large amountsof faba bean, field pea orchickpea seed are spilt.

Watering pointsThe most important fac-

tor influencing sheep perfor-mances during the hot summerperiod is the availability ofgood quality water. Sheep on ahigh protein diet can drinkmore than twice as much waterper day as they do when grazedon other dry feed. Having amovable water point allowsbetter utilisation of feed fromlarge paddocks (see Farmnote106/89 Moving water points onlupin stubbles).


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C R O P S


Main issuesó Weaners tend to concen-

trate their grazing within800 metres of water points.

ó Moving the water point canincrease the utilisation ofthe stubble material.

ó A weaner grazing lupin stub-ble in hot conditions candrink up to nine litres ofwater per day.

ó For water troughs, a fastdelivery is as important asthe water storage capacity.

ó Check the quality of thewater, particularly salt levelsfor young sheep.

ó Clean water troughs everysecond day in hot conditions.

ó Regularly inspect watertroughs to make sure plentyof water is available.

Ground coverFor some grain legume

stubbles the risk of wind erosionfrom a lack of ground coverrestricts the length of grazing. Ageneral recommendation is to

remove livestock from a pad-dock once the amount of plantmaterial present falls below50 per cent ground cover.

Grazing lupin stubblesStubbles of Phomopsis-resis-

tant narrow leafed lupin (Lupinusangustifolius) can provide graz-ing from one to five months,depending on the amount ofresidual seed available; thestocking rate; incidence oflupinosis; the risk of wind erosionand the amount of summer rain-fall (see Farmnote 87/93 Grazingweaner sheep on Phomopsis-resistant lupin stubbles).

There is a greater risk oflupinosis developing in sheepgrazed on the older lupinvarieties such as Danja, Yandee,Chittick and Illyarrie (seeFarmnote 109/88 Grazing man-agement to minimise lupinosis).In the absence of lupinosis, stub-bles from the older varietiesshould produce similar sheepperformances as those obtainedon the phomopsis-resistant vari-eties. Producers should check forinformation on newly releasedvarieties before assuming thatstubbles are safe to graze.

Weight gains can beexpected from healthy wean-ers grazed on lupin stubbleswith adequate seed available.Modern machinery and crop-ping practices have increasedharvesting efficiency to a pointwhere relatively little seed isleft behind and so shorter peri-ods of grazing can be expectedon current stubbles.

Suggested management ofprime lambs grazed onlupin stubbles

ó Train weaners to recogniselupin seed before going ontolupin stubbles.

ó Ensure a plentiful supply ofwater on hot days, up to ninelitres per head per day isneeded.

ó Use a stocking rate of up toten weaners per hectare.

ó Do not graze paddocks witha ground cover less than50 per cent.

ó Consider moving primelambs when seed levels fallbelow 100 kilograms perhectare.

ó Use movable water troughsin large paddocks.

ó Grazing can be deferreduntil late summer but sum-mer rain can spoil feed.

ó Regularly weigh and condi-tion score about 30 animalsin each mob.

Expected weight gainsTrials with Merino weaners

have shown that they can gainup to 15 kilograms during 100

days of grazing on lupin stubble.This gives a growth rate of aboutone-kilogram per week. Sometrials have produced half thisrate, possibly due to sub-clinicallupinosis inhibiting optimumgrowth. Figure 1 provides anexample of how stocking ratescan influence the length of timethat weaners can graze sweetlupin stubbles.

Sheep should be removed from this lupinstubble to avoid wind erosion as groundcover is below 50 per cent.

Suggested grazingstrategy for prime lambs

Lupin stubbles typicallyhave between 150 and 350 kilo-grams per hectare of spilt seedper hectare after harvest. To fin-ish prime lambs, liveweightshould be at least 30 kilogramswhen the lambs are put onto thestubble and there should be atleast 200 kilograms per hectareof seed before grazing begins.The optimum managementtechnique may be to removeprime lambs when the amountof seed falls to about 100 kilo-grams per hectare (this is only asuggestion and not a blanketrecommendation). This is twicethe recommended level of50 kilograms per hectare of seedwhen weaners often begin tolose weight and the risk oflupinosis increases due to higherstem intake. Growth ratesdecrease as the seed becomeslimited and weaners begin to eatmore stem and pod material.

Prime lambs should bemoved to an ungrazed paddockof lupin stubble when feedstarts to become limiting andbefore growth rates begin to

decrease. If there is only onepaddock of lupin stubble avail-able then it might be better toration the feed by temporarilydividing the paddock in half.

Residual grazing of stubbleAfter prime lambs are

removed from lupin stubbles,older sheep such as shippers canthen graze on the remainingmaterial. Older shippers shouldstill gain some weight whereseed levels are between 50 and100 kilograms per hectare.Ground cover may be the limit-ing factor rather than seed levelsbecause lupins are grown pre-dominantly on sandplain soilsthat are prone to wind erosion.

Seed is the mostimportant component

Sheep selectively grazelupin seed rather than leaf orstem material. Seed intake isgenerally high during the firstfew weeks of grazing andgrowth rates are rapid onceanimals are used to the feed.Naturally, the higher the stock-ing rate the shorter the period ofrapid growth.

Lupin seed is high in energy

and lower in starch than cerealgrains, making it a safer feed forsheep. Lupin seed has an aver-age metabolisable energy ofabout 14 megajoules per kilo-gram, less than one per centstarch and about 30 per centcrude protein. However, theselevels can vary considerably andit is important to be aware ofthis and perhaps have the seedtested by a laboratory.

Measuring seed levelsAs a rough guide, an aver-

age of eight lupin seeds in atenth of a square metre (e.g. aHoegrass/Cropcheck square) isequivalent to 100 kilogramsper hectare of lupin seed. Youshould average about 20 ran-dom throws across the paddockto get a reasonably accurateestimation of the amount ofseed in the paddock.

Listed below is the numberof seeds required in aHoegrass/Cropcheck square(0.1 square metre) to be equiva-lent to 100 kilograms perhectare of seed.

Wheat/Oats 28

Barley 25

Lupins 8

Field Peas 5

Chick Peas 5

Faba beans 2

Training weaners torecognise seed

Feeding lupin seed forabout ten days before sheep areput onto stubbles can trainthem to look for spilt seed. As aresult they will eat the seed assoon as they are put onto thestubbles and should start grow-


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LIVEWEIGHTKG

Days of stubble grazing

20 weaners/ha

5 weaners/ha

10 weaners/ha

30

35

40

50

45

0 50 100 150

Figure 1. Liveweights of weaners grazed on Gungurru stubbles at three stocking rates atChapman Valley in 1990-91.


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ing immediately. Another train-ing method is to trail feed lupinsseveral times to the ewes beforetheir lambs are weaned. Thesetechniques are important forprime lamb production wheretime is critical for lambs to reachliveweight targets.

Case exampleA trial was conducted on a

Gungurru lupin stubble nearDoodlakine. Merino weanerswere grazed from 20 December1992 to 16 February 1993. Theweaners increased in liveweightby five kilograms during theeight-week grazing period. Theirgrowth rate was 0.6 kilogramsper week (86 grams per day)and lupin seed decreased from251 to 136 kilograms perhectare during the period ofgrazing. (See Table 1.)

Albus lupin stubbleThe management of sheep

grazing Albus lupin (Lupinusalbus) stubble is similar to thosegrazing narrow leafed lupins.However, the seed is almostthree times bigger and conse-quently sheep select and eat theseed much more quickly. Thiscould easily limit the grazingtime of these stubbles by primelambs to less than a month.

Albus have a higher protein andenergy content than narrowleafed lupins. In addition, Albusvarieties such as Kiev are lessprone to phomopsis infectionthan narrow leafed lupins.

Field pea stubbleThere is considerable expe-

rience with grazing field pea(Pisum sativum) stubbles, whichare high in protein and energymaking them a good feed for allclasses of livestock. Field peaseed is about 25 per cent crudeprotein and has 13 megajoulesper kilogram making peastubbles an excellent source ofdry feed. As with lupins, sheepwill preferentially graze the spiltseed first.

Because of the high starchcontent of peas, sheep are sus-ceptible to acidosis. Introducingsheep gradually to a highstarch diet can prevent this.Enterotoxaemia (pulpy kidney)can also occur when sheep areintroduced to pea stubbles sud-denly and young sheep are moresusceptible than adult sheep(see Sheep Health Issues). Themost effective preventativemeasure is to vaccinate againstenterotoxaemia.

The risk of wind erosion is amajor issue when grazing field

peas. The grazing period forprime lambs is most likely to beless than four weeks (probablymore like two weeks) becausesheep powder up field peastubble and it then blows awayeasily. Extra caution is needed toavoid wind erosion. In conse-quence, pea stubbles shouldonly be grazed to use the spiltseed and then the sheep shouldbe moved to a paddock notvulnerable to erosion (seeFarmnote No 12/88 Introducingsheep to pea stubbles).

Faba bean stubbleGrowth rates for sheep

grazed on faba bean (Vicia faba)stubbles should be similar tolupin stubbles but the seed islarger than narrow leafed lupinsand sheep are likely to target theseed first. About 20 seeds persquare metre (two per Hoegrassor Cropcheck square) equate toabout 80 to 100 kilograms perhectare (see Farmnote 55/96 -Faba bean production). Fababeans have one of the highestharvest indices of the grainlegumes so there is only a smallamount of seed left afterharvest. Faba beans are about27 per cent crude protein,have an energy content of 13 megajoules per kilogram.They are also high in starch.

Theoretically acidosis couldoccur if large amounts of spiltseed remained following har-vest. However, generally fewproblems have occurred withthese stubbles. The stubbleminus the seed appears to begood value so feeding additionallupin seed might be an optionfor prime lamb production if

Table 1. Changes to sheep liveweights and lupin stubble components at Doodlakine

Sheep Lupin Stubble Pod Leaf Stem Crude Digestibilityweight seed DM DM DM DM protein

(kg) (kg/ha) (t/ha) (%) (%) (%) (%) (%)

Start 30 kg 251 4.49 20 34 46 8.0 43

Finish 35 kg 136 2.98 12 32 56 6.2 42

there is still some stubble valueleft. Take care not to overgrazepaddocks with sandy surfacesthat may be prone to wind ero-sion. If the harvester samplerequires grading for size, thefaba bean seconds are an idealsupplementary feed source.

A faba bean crop atMerredin in 1994 yielded 500

kilograms per hectare at harvestwith the amount of spilt seedmeasured at 205 kilograms perhectare. After 19 days of grazingthere were 53 kilograms perhectare of seed left.The 315 July-born ewe weaners (averageweight about 25 kilograms)were grazed on 25 hectares offaba bean stubble and fed20 grams per head per day oflupin seed. They increasedweight at 154 grams per headper day or just over one kilogramper week. In this case a low levelof ground cover was observedand it was suggested that thiscould lead to major problems inbigger paddocks.

Chickpea stubbleChickpea (Cicer arietinum)

stubble is a high value stockfeed that should supply graz-ing for two to three weeks. Thespilt seed is high in value butthe biomass tends to be low.Hence, ground cover is the lim-iting factor. Often the har-vested sample requires grad-ing to meet grain size require-ments and chickpea grain sec-onds make good feed.

Lentil stubbleThe lentil (Lens culinaris) is an

annual winter grain legume thatis inclined to lodge at maturity.Lentils tend to produce a rela-tively low biomass and moderateharvest indices. The green lentilseed is twice as big as the redlentil seed. Evidence from Indiaand Turkey suggests that lentilstubble is usually of high value asa stock feed, although lack ofground cover could limit the graz-ing time to two or three weeks.

Lathyrus stubbleThere is very little experi-

ence with grazing Lathyrus cropstubbles as they are relativelynew on a broadacre scale. Beinga legume crop they should theo-retically support animal grazingat similar rates to chickpeas. Theseed is about half the size of afield pea. Many Lathyrus speciescontain a neurotoxin (ODAP).The consumption of large quan-tities of Lathyrus grain contain-ing high concentrates of theneurotoxin causes some paraly-sis of the lower limbs known aslathyrism in humans and ani-mals. This problem is mainlyassociated with Lathyrus sativusor grasspea.

The dwarf chicklings(Lathyrus cicera) have lowamounts of the neurotoxin.These include varieties such asChalus and Lath-BC. The stubbleand seed of dwarf chickling isnutritious for sheep and cattle.Overseas evidence from prelimi-nary feeding trials suggests thatdwarf chickling grain containsabout 27 per cent crude protein(see Farmnote 24/98 Growingdwarf chickling).

As with field pea stubbles,avoid over grazing, especially onsandy soils where erosion can bean issue. Limited grazing trialshave shown that most seed isconsumed in the first few weeksof grazing. These paddocksshould be closely monitored forlevels of seed and animalsshould be moved to another pad-dock before they begin to loseweight. Expect about two to fourweeks grazing for prime lambs,depending on the amount ofresidual seed left after harvest.

Further reading:Farmnote 24/98.Growing dwarf chickling.

Farmnote 55/96.Faba bean production.

Farmnote 87/93.Grazing weaner sheep onPhomopsis-resistantlupin stubbles.

Farmnote 12/88. Introducingsheep to pea stubbles.

Farmnote 109/88.Grazing management tominimise lupinosis.


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Merino lambs grazing a lupin stubble.Grazing pressure around water points onlupin stubbles will be high and can leadto a risk of erosion.


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K E Y M E S S AG E Só The gross margins from grazing sheep on mature, grain-legume crops such as

lupins can be greater than that achieved by harvesting and selling of the grain.ó Weaners can be grazed at considerably higher stocking rates on mature grain-

legume crops than the stubbles from these crops.ó Young sheep have achieved growth rates of 1.1 to 1.5 kilograms per head per week

when grazing mature crops.

IntroductionA strategy to finish prime

lambs, or shippers, during sum-mer and autumn is to sow anarea to a grain legume crop,allowit to mature and leave it standingfor use as sheep feed rather thanharvest the grain. Seeds fromsweet lupins, faba beans andfield pea crops are a good sourceof energy and have the high levelof protein that is needed byfast-growing young sheep. Sheepcan be grazed on the maturecrop at higher stocking rates thanare possible on pastures or stub-bles during summer and autumnand still achieve good rates ofanimal growth.

Results from trialsA trial using six-month-old

crossbred ewe lambs (SouthSuffolk x Merino) conductednear Northam in 1995/96 indi-cated that the grazing of maturelegume crops (lupins and fieldpeas) could generate greatergross margins per hectare thanare possible from harvestingand selling the grain. This resultdepends on grain type and pre-vailing commodity prices.

The higher gross marginsgenerated in the trial weremostly due to the use of consid-erably higher stocking rates thanthose normally used to graze

stubbles. The lambs were grazedfor six weeks and the growthrates varied from 1.2 kilogramsper head per week for the high-est stocking rate of 49 perhectare to 1.5 kilograms perhead per week for the loweststocking rate of 28 per hectare.

Similarly, a South Australianstudy using young Merinowethers grazed at 40 per hectarefor six weeks, found that underdry summer conditions grainlegume crops could producegrowth rates of more than1.1 kilograms per head per week(that is, more than 160 gramsper day).

Keith Devenish, Department of Agriculture, Northam

Grazing Sheep on Matured GrainLegume Crops


C R O P S

Practical applicationSweet lupins are the crop

most likely to show promise forthis strategy because the grain isusually worth less than theother grain legume crops andthere are fewer problems fromacidosis. In addition, the stock-ing rates can be significantlyhigher on these crops and thegrazing period will be longerthan that obtained when onlythe stubbles are grazed.

Animal health issuesSheep may need to be intro-

duced to the crops gradually toavoid acidosis, especially forfield peas or faba beans. Theywill also need to be monitoredclosely while grazing lupins tominimise their chances of devel-oping lupinosis (see section onSheep Health Issues).

Further readingWarner, K.S.A.; Hepworth, G.W.;Davidson, R.H. and Milton, J.T.B.(1998). Grazing Mature GrainLegume Crops. Proceedings ofthe Australian Society of AnimalProduction 22: 217-220.

Standing lupin crops provide an excellent feed resource for finishing lambs.

C R O P S


K E Y M E S S AG E Só Cover cropping legume pasture with a small amount of sweet lupin seed improved

the performance of crossbred lambs grazed on matured medic pasture over summer.

ó Sowing 15 kilograms of lupin seed per hectare with medic reduced the medic seed yield by less than ten per cent whereas sowing 30 kilograms of lupins per hectare reduced the seed yield of medic by 30 per cent.

ó Weekly growth rates of up to 1.4 kilograms per head were achieved for crossbred lambs when lupins were added to the pasture mix.

Keith Devenish, Department of Agriculture, Northam and Gary Hepworth andNatalie Coonan, Curtin University of Technology, Muresk, Northam

Increasing Lamb Growth onMedic Pasture Cover Croppedwith Sweet Lupins

IntroductionIn the past, farmers have

often under-sown oats withsub-clover to provide sheepwith a cheap but valuable sum-mer feed.

The usual recommendationfor establishing a medic pastureis to sow it as a pure stand.However, one prime lamb pro-ducer has found that lupins areideal to sow with new medic pas-ture; helping to increase growthrates of sheep without reducingthe pasture’s seed yield.

This technique has nowbeen evaluated for use withsheep meat enterprises; theresults of which are detailedbelow.

Trial resultsA grazing trial was con-

ducted during the summer of1996/97 on a farm at Perenjori.Santiago medic pasture wasestablished on a red loamy soilwith,or without,a small amountof sweet lupin seed that wasmixed with the medic at seedingtime. The trial investigated theamount of lupin seed that canbe sown with medic seed beforethe seed yield of medic isreduced. The benefits of usingthis pasture mix for prime lambproduction were also evaluated.

The newly sown pasturewas allowed to mature beforethe area was fenced into one-hectare plots. Each plot was

stocked with store lambs (BorderLeicester x Merino) at 6 DSE perhectare for eight weeks from18 December to 12 February.The average weight of the lambsat the beginning of the trial was32 kilograms.

The growth rates of thecrossbred lambs grazed on apure medic pasture sown with15 kilograms per hectare of seedwere compared with those ofsimilar lambs grazed on medicpastures mixed with either 15 or30 kilograms per hectare of sweet lupins (Merrit).

At the conclusion of thegrazing period, all lambs weretransported to the Linley ValleyAbattoir where they were


C R O P S

slaughtered and each carcasewas evaluated in terms of itsdressed weight and carcasequality.

Similar amounts of plantdry matter were produced byall treatments. Lambs on themixed medic/lupin pasturegrew more than twice as fast(172 to 206 grams per head perday) as those on the pure medicpasture (63 grams per head perday) (Table 1).

There was also a large dif-ference in carcase value; withthose from the lupin treatmentsachieving double the value ofthose grazed on pure medic pas-ture ($35.33 and $40.65 com-pared to $18.63 respectively).This was mainly because thedressed weight and conditionscore of lambs from the puremedic pasture failed to reachoptimum slaughter weight andcarcase characteristics.

Adding 15 kilograms perhectare of lupin seed to themedic at seeding only reducedthe seed yield of the medic bynine per cent. However, at 30

kilograms per hectare, thelupins reduced the seed yield ofthe medic by 30 per cent.

ConclusionSowing a small amount of

lupin seed as a cover crop withmedic pasture increased theperformance of prime lambsgrazed on the mature pasture.

The pure medic pasture(more than 80 per cent medic)only produced a growth rate of 0.44 kilograms per head perweek compared to the medic-lupin pasture which increasedthe growth rate to more than1.2 kilograms per head per week.At low seeding rates of lupins, theimpact of competition on medicseed production is minimal.

Cover cropping with lupinsprovides the opportunity to fin-ish prime lambs (or any othermeat sheep) during summerwhile recovering the costs asso-ciated with establishing a newlegume pasture.

Table 1. Growth rates and carcase values of prime lambs grazed on medic pastureswith and without a narrow-leafed lupin cover crop

* Assumptions: initial lamb value $15 per head, stocking rate 6 head per hectare

Pasture Medic Lupin Weight Growth Final Dress Carcass Meattreatments seed grain gain rates weight weight value value

(kg/ha) (kg/ha) (kg/hd) (g/hd/d) (kg) (kg) ($/hd) ($/ha)

Medic 822 0 3.38 63 36 13 18.63 22

Medic + 15

kg/ha lupins 747 317 9.52 172 42 17 35.33 122

Medic + 30

kg/ha lupins 570 474 11.60 206 44 19 40.65 154

F O D D E RRoy Butler, Department of Agriculture, Merredin and

John Milton, Department of Agriculture, based at theUniversity of Western Australia, Nedlands


F O D D E R

K E Y M E S S AG E Só Fodder is the term that is usually applied to conserved roughages, but it may also

refer to standing green crops (“fodder crops”) or pastures.ó Silage, hay and straw are the most familiar fodders, however hay-frozen pasture or

crop and windrowed pasture can also be used as fodders.ó Rarely does any fodder, alone, provide a complete diet suitable for growing or

finishing sheep for slaughter.ó The nutritive value of different fodders is highly variable and difficult to estimate.

Therefore, a laboratory analysis is recommended when planning a feeding programusing fodders.

Fodder is not acomplete ration

Fodder provides somenutrients for sheep and also hasan important role in maintain-ing normal rumen function.Fodder alone, however, is rarelysufficient for prime lamb pro-duction. For older sheep, somehigh-quality fodders can providea maintenance or slow-gaindiet. More commonly, somegrain or other concentrate isrequired in addition to the fod-der. The higher the nutritivevalue (or quality) of the fodder,the more grain it can replace in asheep’s diet.

When given a choice, andfed ad libitum, sheep will gener-ally consume a mixture com-prising 15 to 40 per centroughage and 60 to 85 per centconcentrate (grains). The preciseproportions eaten will varyaccording to the palatability andnutritive value of the differentfeeds. Each day a sheep will con-sume a total weight of feed (con-centrate plus roughage) equal toapproximately two to four percent of its body weight.

Possible problemswith fodder

Some of the problems asso-ciated with fodder are obviousand well-known, while othersmay be unexpected:

ó Bulk and weight - Specialequipment may be requiredfor handling fodder, andlarge structures for its stor-age. There may be occupa-tional health and safety haz-ards in lifting bales.

ó Cost - Fodder may be anexpensive source of energy ifenergy is the primary need.

ó Wastage - is generally high(30 to 80 per cent) in feedingout fodder, unless specialmeasures are taken.

ó Weeds - such as rye grass,barley grass, Paterson’s curseand radish are readilyspread in hay. The risk ofweed introduction in silageis much less.

Without chemical treat-ment, the quality of conservedfodder can only, at best, matchthat of the parent material.Therefore, whatever the fodder,the choice of the base plantmaterial and the time of cut-ting, are the critical factors thatdetermine the final nutritivevalue of the fodder.

The cost of fodderFodder can be relatively

expensive, especially on a costper unit of protein or energybasis. In addition to the cost ofgrowing it, there are costs withharvesting, storing and feedingit out. Insect and vermin control,further treatment, processing ormixing and wastage all add tothe cost of a conserved fodder bythe time it is actually consumedby an animal. When calculatingthe cost of fodder, and whencomparing the cost of differentfodder options, the best mea-sure to use is the energy contentof the fodder per kilogram of drymatter. This is expressed asmegajoules of metabolisableenergy per kilogram dry matter.

F O D D E R


ó Diseases - Hay made fromlupins, (especially blue lupins)may cause lupinosis.Hay maycontain toxic rye grass seed-heads that can cause annualrye grass toxicity (ARGT). Thefungi in mouldy hay cancause abortions, feed refusalor respiratory problems instock. Mites, dust and possi-bly fungi in hay can causerespiratory problems inhumans (farmer’s lung).Silage that has not beenadequately fermented, orhas been exposed to the air,may contain Listeria bacteriathat can cause abortions orencephalitis (circling disease).

Test fodder fornutritive value

For most types of conservedfodder the nutritive value, interms of protein and metabolis-able energy, is highly variableand not easy to estimate. Thedata recorded in Table 1 showthe wide variation in the nutri-tive value of a number of differ-ent types of fodders fed to sheepin Western Australia.

Ideally, samples of each dif-ferent batch of fodder should besubmitted for a laboratoryanalysis.This is especially impor-tant when purchasing largequantities of conserved fodders.

Some vendors will supply thisinformation for their produce.

If fodder is unable to betested in a laboratory it shouldat least be closely inspected.Check its smell, colour and den-sity, look for weeds and any signof moulds. In pasture hay checkthe proportion of legumes tograsses. Sheep are very selectivefeeders and may refuse mould,insect or vermin affected feed. Ifa hay or straw contains annualrye grass and comes from a dis-trict where ARGT is known tooccur, a sample of the rye grassshould be tested1 to determineits safety for stock.

Table 1. The dry matter, energy, protein and fibre content (dry matter basis) of green fodders fed to sheep. The average across therange of values is shown in brackets.


1Further information is available via AgFax 1902 990 506, Document number 20224, or contactAndrew Gregory, ARGT Testing Service, Animal Health Laboratories, Department of Agriculture, South Perth WA 6151

Green fodders Dry matter Metabolisable energy Crude Protein Acid detergent fibre (%) (MJ/kg) (%) (%)

Cerealsearly growth 12 - 22 (17) 9.5 - 11.0 (10.5) 14.0 - 24.0 (18.0) 23.0 - 27.0 (25.0)

before heading 18 - 30 (25) 9.0 - 10.2 (9.5) 9.0 - 15.0 (12.0) 28.0 - 32.0 (30.0)

PastureEarlygrass - dominant 10 - 20 (15) 10.0 - 11.8 (10.5) 20.0 - 27.0 (23.0) 22.0 - 26.0 (24.0)

clover - dominant 10 - 20 (15) 10.0 - 12.0 (10.8) 24.0 - 32.0 (27.0) 21.0 - 25.0 (23.0)

Floweringgrass - dominant 20 - 30 (25) 9.5 - 10.5 (10.0) 10.0 - 15.0 (12.0) 28.0 - 33.0 (31.0)

clover - dominant 20 - 30 (25) 9.8 - 10.8 (10.3) 13.0 - 18.0 (15.0) 26.0 - 31.0 (29.0)

Millet for grazing 15 - 30 (22) 9.0 - 11.0 (10.5) 9.0 - 24.0 (17.0) 24.0 - 32.0 (29.0)

Sorghum hybridsimmature 12 - 20 (17) 9.5 - 10.5 (10.0) 15.0 - 22.0 (17.0) 24.0 - 29.0 (27.0)

heading 25 - 35 (30) 9.0 - 10.0 (9.5) 7.0 - 14.0 (10.5) 28.0 - 34.0 (32.0)

Lucerneimmature 12 - 20 (17) 9.8 - 11.2 (10.5) 22.0 - 33.0 (26.0) 24.0 - 27.5 (25.5)

10% flowering 20 - 30 (25) 9.2 - 10.2 (9.6) 15.0 - 22.0 (18.0) 28.0 - 34.0 (30.0)

Annual Ryegrass 10 - 30 (22 8.5 - 11.5 (10.0) 10.0 - 30.0 (14.0) 21.0 - 30.0 (28.0)

Perennial Ryegrass 12 - 30 (22) 8.5 - 11.5 (10.0) 10.0 - 30.0 (14.0) 21.0 - 30.0 (26.5)

Phalarisclosely grazed 12 - 27 (20) 9.0 - 11.0 (10.0) 14.0 - 28.0 (17.0) 21.0 - 28.0 (26.0)

SilageCompared with hay, there

can be a number of advantagesin making silage:ó Silage will generally be of

higher nutritive value thanthe corresponding hay. Thisis because silage is normallymade at an earlier stage ofplant growth, when itsdigestibility, protein andmetabolisable energy levelsare higher.

ó The plant re-growth thatmay occur after cutting

silage provides a valuablegrazing bonus by extendingthe growing season of a pas-ture or crop.

ó This regrowth forage, havingnot been grazed, should befree of worms and will pro-vide valuable feed for graz-ing by weaned lambs.

ó Early cutting of pasture forsilage favours clover growthand removes excess foragethat often shelters pasturepests such as the red-leggedearth mite.Farmers interested in con-

serving silage may be concernedabout the cost of the machineryrequired to make it and feed itout, and also the time requiredand possible wastage duringfeeding out. If no more than200 tonnes of silage dry matteris to be made, a contractor islikely to be the least-cost choice.There are contractors equippedfor, and experienced in, silagemaking in most areas ofWestern Australia. Feeding outalso need not be a problembecause various simple systemscan be devised, including a self-feeding system from the face ofa stack of chopped silage.

Silage made from pastureor cereal crops can be quite highin nutritive value, but it will notprovide a complete diet for fin-ishing sheep. Silage made froma mixture of a cereal and alegume, such as vetch, peas, aclover or a medic, may, however,have a high enough nutritivevalue to allow growth of lambswithout the need for grain sup-plementation. The variability inthe nutritive value of silages isshown in the values in Table 2.

Silage can be conserved inwrapped round bales, pits orabove ground stacks. Baled andwrapped silage is likely to be themost expensive option, but it ispreferred by the majority offarmers because of the ease offeeding-out and the conve-nience of using bales. Whatevermethod is used to make silage,it is important to ensure ade-quate compression and exclu-sion of air.

The performance of lambsfed bale silage can be quite goodif the forage is wilted to a drymatter content of around 50 percent before baling, especially ifthe parent forage has a goodpercentage of legume. Being oflower moisture content, this willreduce the cost of storing nutri-ents as bale silage.

Urea treated cereal silage In Western Australia, most

silage is made without addi-tives, but urea treatment ofcereal crops is a technique thatmay be of interest to wheatbeltfarmers. For urea treated silage,the cereal crop is harvested atthe medium to hard doughstage, when the dry matter con-tent is 60 to 70 per cent. This isin contrast to the usual high-moisture silages that are har-vested at around 30 to 35 percent dry matter. The urea can beapplied dry by thorough mixingwith the chopped crop materialor it can be applied at baling. Ifthe cereal crop is above 70 per-cent dry matter it may be best toapply the urea as a solution.The urea treatment procedureshould improve the digestibilityand nitrogen levels compared


F O D D E R

Wrapped silage in the Porongorups.

Well covered silage stack at DenmarkAgricultural College.


F O D D E R

with conventional fermentedsilage. It may also be a usefulway to salvage frosted wheat orbarley crops.

HayHay is the product from a

cut and dried pasture or crop. Itcan be made into large roundbales, or small, medium or largesquare bales. Large round balesare the most popular, being thecheapest to make and safest tostore in the open,uncovered. Hayis usually baled, but if requiredfor chaff it is sometimes har-vested with a reaper and binderand made into sheaves.

In general, the later the hayis cut the higher the yield(in tonnes per hectare), butthe lower the nutritive value ofthe hay, due to a decline in pro-tein content and digestibility.For cereal hay, yield will behighest if cut in the mid tolate dough stage, but proteinand metabolisable energy con-tent will be highest if the hay iscut between flowering and themilk stage.

If hay feeders are poorlydesigned or maintained, or ifhay is fed on the ground in wetweather, wastage levels can behigh, even if the hay is verypalatable. Hay wastage can havea significant effect on profitabil-ity when feeding carry-overlambs in autumn. In a studyreported in the December 1998

issue of the ‘Ovine Observer’,Milton and Davidson showedthat 43 per cent less hay wasrequired to finish crossbredlambs fed from a covered rackcompared to a control groupoffered the same hay uncoveredin the bale on the ground. Thegrowth rates and carcase char-acteristics of the two groups oflambs were similar but the over-all feed costs (including thesame amount of grain fed toeach group) were 26 per centless for those fed the hay in acovered rack.

Cereal hayMost cereal hay is made

from oats or wheat. In thewheatbelt, cereal hay is fre-quently made from crops sownfor grain production,rather thanfor hay. Hay is commonly madefrom firebreaks and sometimesfrom failed, diseased or frostedgrain crops.

Hay made from firebreakscan be of good quality if cut atthe right stage of maturity, but ifit is not given priority as a haycrop, it may be cut too late foroptimum nutritive value. Haythat is made to salvage a dis-eased crop may be of poor qual-ity for sheep, due to low palata-bility or low energy or proteinlevels. However, a frosted orfailed crop may produce a hayof reasonable protein andmetabolisable energy content ifit is not allowed to deteriorate

Wrapping hay bales reduces waste anddeterioration.

Table 2. The dry matter, energy, protein and fibre content (dry matter basis) of silages.The average across the range of values is shown in brackets.

These figures have been extracted from data collected by Independent Lab Services, Perth.

Silages Dry matter Metabolisable Crude protein Acid detergentenergy fibre

(%) (MJ/kg) (%) (%)

Pasturedirect-cut(chop) 21 - 33 (25) 8.5 - 10.5 (9.5) 12.0 - 22.0 (16.0) 28.0 - 35.0 (33.0)

wilted (chop & bale) 35 - 55 (45) 8.8 - 10.8 (9.8) 12.0 - 25.0 (17.0) 28.0 - 33.0 (32.0)

Sorghum hybrid 25 - 35 (30) 8.0 - 9.0 (8.5) 6.0 - 10.0 (8.0) 32.0 - 35.0 (34.0)

Cereal crops(bale) 35 - 45 (40) 8.5 - 9.8 (9.1) 7.0 - 13.5 (9.5) 29.0 - 35.0 (32.5)

Cereal/Vetch 35 - 45 (40) 8.8 - 10.0 (9.7) 10.5 - 16.0 (13.0) 30.0 - 33.0 (31.0)

Lucerne (bale) 45 - 55 (50) 9.1 - 10.7 (9.5) 15.0 - 28.0 (22.0) 29.0 - 33.5 (30.5)

before being cut. Frosted cropsmay produce a hay that is read-ily eaten by sheep as the sugarstrapped in the plant materialmay make the hay very palat-able. As it is difficult to predictthe nutritive value of these hays,laboratory testing is stronglyrecommended.

Oaten hay is usually madefrom a crop grown specificallyfor hay production. Hay varietiesinclude Esk, Hay, Kalgan, Saia,Swan, Winjardie and Vasse. It isimportant to seek advice onthe oat hay varieties most suitedto your region and the appropri-ate agronomic practices forhay production.

Only a relatively smallamount of wheaten hay is madefrom crops grown specifically forhay. The only hay variety isBaroota Wonder. Most wheatenhay is made from varieties thathave been bred solely for theirgrain-related qualities.

The average nutritive val-ues of Western Australian haysare recorded in Table 3.

Hay made from bearded (orawned) wheat may cause prob-lems, such as impaction andabscesses, particularly in themouths of cattle and horses.However, such problems arerarely observed or reported insheep in Western Australia. Thisis curious since most of thewheat varieties grown inWestern Australia are bearded.

Cereal hay containingtoxic rye grass has beenresponsible for ARGT deaths in

sheep, cattle and horses inWestern Australia. If there is apossibility that hay may con-tain toxic rye grass, testing isstrongly recommended.

If a cereal crop is to be sownspecifically for hay, considerinstead to sow a mixture of acereal and a legume.The legumemay be a vetch, pea, clover ormedic. The cereal and legumevarieties chosen to growtogether should have similarflowering times.


F O D D E R

A firebreak is created when hay is madearound the perimeter of a crop.

Table 3. The dry matter, energy, protein and fibre content (dry matter basis) of hays fedto sheep. The average across the range of values is shown in brackets.


Hays Dry Metabolisable Crude protein Acid detergentmatter energy fibre

(%) (MJ/kg) (%) (%)

Oaten

early-cut 90 8.8 - 10.2 (9.1) 7.0 - 12.5 (8.5) 25.0 - 32.0 (30.0)

late-cut 90 8.0 - 9.0 (8.5) 4.0 - 7.5 (6.0) 30.0 - 37.5 (32.5)

Wheaten

early-cut 90 9.0 - 10.0 (9.4) 8.0 - 11.5 (9.5) 25.0 - 31.0 (29.0)

late-cut 90 8.0 - 9.0 (8.6) 4.5 - 7.5 (6.5) 30.0 - 36.0 (32.0)

Barley

early-cut 90 9.0 - 10.0 (9.4) 8.0 - 11.0 (9.2) 25.0 - 31.0 (29.0)

late-cut 90 8.0 - 9.0 (8.6) 4.5- 7.5 (6.5) 30.0 - 36.0 (32.0)

Pasture

Grass dominant

early-cut 88 9.0 - 10.8 (10.0) 12.0 - 18.0 (14.5) 24.0 - 30.0 (28.0)

late-cut 88 8.0 - 9.5 (9.0) 8.0 - 12.0 (10.0) 30.0 - 34.5 (32.5)

Clover dominant

early-cut 88 9.5 - 11.2 (10.2) 15.0 - 23.0 (17.0) 23.0 - 29.0 (27.5)

late-cut 89 8.5 - 9.8 (9.5) 11.0 - 15.0 (12.5) 30.0 - 33.0 (32.0)

CLIMA legume 89 9.3 - 11.1 (10.2) 14.0 - 20.0 (16.0) 27.0 - 32.0 (29.5)

Cereal/Vetch 88 9.0 - 10.0 (9.5) 10.5 - 15.5 (13.0) 29.5 - 32.0 (31.0)

Pea 88 9.0 - 10.0 (9.5) 13.0 - 17.0 (15.5) 30.0 - 33.0 (31.5)

Lucerne

early-cut 88 9.8 - 10.5 (10.0) 20.0 - 30.0 (26.0) 27.0 - 29.0 (28.0)

late-cut 89 9.0 - 9.8 (9.5) 13.0 - 20.0 (15.0) 30.0 - 33.5 (32.0)

Table 3. The dry matter, energy, protein and fibre content (dry matter basis) of hays.The average across the range of values is shown in brackets.


F O D D E R

A mixed cereal-legumehay crop is potentially superiorto oaten hay for the followingreasons:ó The nutritive value for sheep

will be greater, because it islikely to be more palatableand have a higher protein,calcium and metabolisableenergy content.

ó A following grain crop maybenefit from the extra nitro-gen provided by the legume.

ó A greater weight of hay – asmuch as 20 per cent more -may be cut from the paddockthan from the cereal alone.

ó After the hay is cut, the pad-dock will provide more graz-ing because it will be morenutritious than that providedby a cereal stubble alone.

Pasture hayThe composition, and there-

fore the feed value, of pasturehay can be extremely variable.Generally, the higher the legumecontent the better. Rememberthat pasture hay may containnuisance or toxic weeds, such asPaterson’s curse, bracken, barleygrass, Cape tulip or herbicide-resistant or toxic rye grass.

Windrowed pastureThe technique of mowing

and windrowing spring pasture,to be grazed in situ later, hasbeen suggested as a low costalternative to the making of pas-ture hay or silage.

David and Lyn Slade, ofRocky Gully have followed thispractice on their farm for someyears, in preference to spray top-ping. The Slades mow their pas-

tures in spring primarily to min-imise grass-seed damage to theskins of their prime lambs. Theadditional benefit, they believe,is that in seasons of abundantgrowth the large windrows havea thick thatched surface thatprotects and preserves thenutritive value of the underlyingmown pasture.

Lucerne hayLucerne is sometimes

referred to as the “King ofFodders”, for good reasons.Well-made lucerne hay is ahighly valued fodder, particu-larly by feed millers, fodderexporters and horse owners. Itcan be an excellent feed for sheepbut it may not be economic tofeed it to them, especially ifthe feeding system allows highwastage, by shattering ofthe most valuable component,the leaves.

Lupin hay.Lupin hay is a very palatable

fodder, of reasonable quality, forsheep. However, the differenttypes of lupins present differentrisks from lupinosis.

With the commercial nar-row-leafed lupins, lupinosis canbe avoided by cutting the lupinsno later than the finish of flow-ering on the tertiary branches.Rapid drying is necessary, so it isrecommended to condition thelupins as they are cut.

The strategic cutting timeand rapid drying are crucial toavoid lupinosis. Unfortunately,the conditions are more difficultto be met with the blue or sand-plain lupin.These plants are self-

sown and there is always a con-siderable variation in the stageof growth of plants in the stand.They also tend to have thickerstems than the narrow-leafedlupins, so take longer to dry. Theend result is that although sand-plain lupin hay will be less toxicthan adjacent standing lupins,the toxicity is often not reducedsufficiently to avoid lupinosis.Cutting the sandplain lupinscloser to the start of floweringmay overcome these problems.However, this reduces theamount made and wet weatheris more likely to be encounteredduring the drying period.

Hay frozen pasture or cropHay freezing is the practice

of spraying a green pasture orcrop with a herbicide, such asglyphosate or paraquat, to stopfurther growth and conserve thenutritive value of the standingplants for later grazing in situ. Asimilar practice, called brownmanuring, is done primarily forweed control.

The nutritive value of hayfrozen fodder can be quite high,depending on its componentsand time of spraying. Time andlabour are saved comparedwith conventional hay making.The technique is not suitablefor areas with wet summersbecause rain will leach outand break down the nutrients inthe plants.

Case study - A hay-frozenmixed fodder crop atSouth Kumminin

In 1994 Alan and RaySedgwick at South Kummininsowed a cereal-legume mix(oats/lupins) and fertilised it butdid not control weeds. In addi-tion to the oats and lupins, thepaddock contained cape weed,radish and medic. The paddockwas sprayed with Gramoxone®when the lupins were flowering.The following analysis is theaverage of two samples of theavailable feed taken from thepaddock in mid-January, 1995:

Moisture (%) 6.4Dry matter (%) 93.7Acid detergent fibre (%) 30.6Digestible dry matter (%) 65.7Est. metabolisable energy(MJ/kg DM) 9.3Crude protein (%) 13.8

Five hundred and ninetyMerino ewe lambs spent 32 dayson this paddock, from 12

January 1995, and they gainedan average of eight kilograms, oran average daily weight gain of250 grams per head per day.

The Sedgwicks term theirpractice ‘stubble mulching’.Theypractise it primarily for thebenefits it gives to the land andthe following crops. They con-sider that the practice aids soilstructure, weed control andimproves the soil nitrogen lev-els. The benefits provided totheir stock are a bonus!

StrawMost types of straw provide

only roughage for sheep. This isbecause most have high levels ofindigestible material and a lowprotein content. Not surpris-ingly, they are also usuallynot palatable to sheep.Nevertheless, the straws col-lected from the header rows oflow yielding crops produced inthe 2000 growing season havebeen found to be of quite goodnutritive value. Furthermore,the performances of sheep thatgrazed the 2000 season stub-bles, as well as their utilisationof these stubbles, amazed manysheep producers. Again, a goodreason why baled straws shouldbe tested for protein andmetabolisable energy content.

Various methods have beentried to improve the nutritivevalue of cereal straws. Thesehave included treatment withsodium hydroxide, ammonia orurea, or spraying with molasses.The treatments are relativelyexpensive, and some are poten-tially dangerous to the operatoror toxic for sheep. In any case, nomatter how straw is treated,sheep will lose weight if that isall they are fed.


F O D D E R

Further readingBarr, A.R. and Pelham, S (1996).Growing Oat Hay. KondininGroup, Belmont WA.

Casey M. (Ed.) (1994).Cut and Dried. Kondinin Group,Belmont WA.

Evans, M. (Coordinator) (1997).Fodder Costs. Kondinin Group,Belmont WA.

Farmnote 98/99.Fodder conservation as silage.

Feeding Sheep.(Revised December 1997).Edited by Brian Ashton and TonyMorbey. Primary Industries andResources South Australia.

Maximum meat: the completeguide to producing qualitymeat sheep. Department ofAgriculture. 1998.

Supplementary Feeding of SheepF O R M E AT P R O D U C T I O NJohn Milton, Department of Agriculture, based at The

University of Western Australia, Nedlands and JanetPaterson, Sci Scribe Scientific Copywriting, Brookton.


Supplementary Feeding of Sheep FOR MEAT PRODUCTION

K E Y M E S S AG E Só The correct supply of protein and energy is required to maintain good rumen

function for the efficient conversion of feed into meat.ó Supply the rumen microbes with the nutrients that are limiting in the sheep’s diet

for cost-effective supplementary feeding.

Supplementary feeding Sheep are supplementary

fed for either survival, or for pro-duction: reproduction, lactation,weight gain or wool growth.Efficient supplementary feedingof sheep for meat productionaims to supply sheep with themain nutrients that are defi-cient in their normal basal diet.

The main nutrients thatlimit growth are energy and pro-tein. Both nutrients are requiredfor healthy rumen function andthe efficient conversion of feedinto meat products.

Feeding for energyTo maintain liveweight,

each day a sheep will requireabout 10 per cent of its body-weight as metabolisable energyplus a further 1.8 megajoules ofenergy. For example, a 50 kilo-gram sheep requires 5 + 1.8 or6.8 megajoules of metabolisableenergy per day (see Table 1). Thisestimate appears to be gener-ous and there are examples of50 kilogram sheep during con-finement feeding, maintainingtheir weight when fed a diet tosupply only 5.5 megajoules ofmetabolisable energy per day.That is, about 80 per cent of therecommended requirement formaintenance.

The average metabolisableenergy content of oaten grain is10.7 megajoules per kilogram ofdry matter (see Table 2). The50 kilogram sheep in the exam-ple above will therefore need635 grams of oats each day(6.8 megajoules divided by10.7 megajoules multiplied by1000) to maintain liveweight.In reality, about 700 grams ofoats would need to be fed totake into account the 8 per centmoisture in the oaten grain andany wastage that may occurduring feeding.

Lupins contain more meta-bolisable energy than oats (atabout 13.7 megajoules per kilo-gram of dry matter) and there-fore fewer lupins are required tomaintain the liveweight ofsheep. A 50 kilogram sheepwould maintain liveweight onabout 500 to 550 grams oflupins per day.

When feeding for energy itis best to work out the cost ofeach megajoule of metabolis-able energy to determine whichfeed is most economical. Forexample, oaten grain with10.7 megajoules per kilogram ofdry matter and 7 per cent mois-ture priced at $100 per tonne,costs around 11 cents per kilo-gram of dry matter. The priceper megajoule of metabolisable

energy is therefore 11 dividedby 11 or one cent per megajoule.This calculation can be donewith any feed using the currentprice per kilogram for that feed.

How to use Table 1:

A 50 kilogram sheep (shorn)needs 6.8 megajoules of meta-bolisable energy per day tomaintain its liveweight. This canbe supplied with 0.54 kilogramsof a feed that contains 12 mega-joule per kilogram (for examplewheat grain) or 0.68 kilogramsof a feed such as oats containing10 megajoules of metabolisableenergy per kilogram.

Feeding for protein andgood rumen function

To use the energy suppliedin the diet efficiently, a goodsource of protein must also beprovided. Supplementary feed-ing with feeds that are high inenergy but low in protein willlead to poor rumen functionand inefficient conversion offeed into meat products. This isbecause the microbes in therumen need a protein source toreproduce and grow and tomaintain their population.

If the protein in the diet islow, the microbial populationdeclines and consequently less



microbial protein is available tothe sheep for growth. In addi-tion, if the microbial populationis lowered, there are fewermicrobes to break down the feedeaten by the animal and feed iswasted through inefficientdigestion. Feed intake also willbe reduced as a result of theslowing of digestion in therumen since the rate at whichfeed particles are broken downand leave the rumen willdecline. Thus, there will be lessspace available in the rumen formore new food to enter.

An example of this is whenadult sheep are fed straw aloneto maintain their liveweight.Straw is made up largely of com-plex carbohydrates (energy) andis inherently low in protein - aslittle as three per cent crude pro-tein content. Because of this, therumen microbes become defi-cient in protein and are not ableto maintain their population.Less microbial protein is thenavailable for the sheep to con-vert into muscle or meat.

As the microbial populationdeclines, the straw can not be

fully digested and the energy itcontains remains unavailable tothe sheep. This reduction indigestion causes the feed to bulkup in the rumen of the animaland will lower its rate of feedintake. All of these factors com-bine to cause the animal to loseweight and body condition.

In this case, adding a pro-tein-rich feed such as lupinswould improve the protein sup-ply to the rumen microbeswhich in turn will allow thesheep to make better use ofthe energy available in thestraw. As little as 80 grams oflupins per day may provide theextra protein required by anadult sheep grazing dry pas-tures or cereal stubbles or beingfed a low-quality hay.

The protein and energy con-tents of feeds can vary widelybetween and within paddocksand years, and between varietiesand for different fertiliser inputs,so it is important to have feedstested for protein and energylevels. Knowing the protein andenergy contents of feeds is par-ticularly important when grow-

ing sheep out for meat produc-tion; it will help with ration for-mulation and for comparing thecosts of different feeds on anutrient basis as well as reduc-ing wastage of feedstuffs. Theranges in protein and metabolis-able energy contents of somecommon feeds fed to sheep inWestern Australia are given inTables 2 to 5 in this section.

Problems with grainsupplements

Apart from being a goodsource of protein, lupins alsohave a major advantage overcereal grains and most othergrain legumes because theycontain virtually no starch (aform of carbohydrate). Thestarch in these other grains israpidly fermented in the rumento produce acidic conditions(that is, a lowering of pH). Alow pH will eventually kill thefibre digesting microbes in therumen and consequently reducethe amount of energy andprotein that becomes availableto the sheep. In this situation,the sheep will reduce theirfeed intake and substitutethe supplementary grain fordry roughage.

In the worst case scenario,there may even be a ‘negativeefficiency of supplementation’when the intake of the basalforage is reduced by more thanthe amount of supplementarygrain eaten. In other words, theconsumption of the supplemen-tary feed actually causes the ani-mal to lose weight rather thanmaintain or gain weight. This istypical of what can happenwhen sheep are supplemented

Table 1. The energy (megajoules per day) and kilograms of feed needed to maintainsheep of different weights

Shorn Paddock Energy Metabolisable energy content of feed weight weight requirement 8 9 10 11 12

(kg) (kg) (MJ/day) (MJ/kg DM)

feed needed (kg/head/day) for maintenance

20 21 3.8 0.44 0.38 0.33 0.3 0.26

30 32 4.8 0.59 0.52 0.46 0.41 0.36

40 43 5.8 0.75 0.65 0.57 0.51 0.46

50 54 6.8 0.89 0.77 0.68 0.61 0.54

60 64 7.8 1.03 0.89 0.78 0.7 0.63

with cereal grain at the end ofthe pasture growing season. Inthis case, feeding a smallamount of lupin grain is the bestform of supplementary feedingto supply protein and energy toencourage the utilisation of thedry roughage.

Although lupins are a goodsource of protein, the nitrogen(N) to sulphur (S) ratio can be toowide and cause deficiencies ofparticular amino acids in theanimal. In this case, microbialprotein synthesis may bereduced and the protein sup-plied to the sheep’s small intes-tine may not contain adequatesulphur amino acids for bothwool and muscle growth.

A wide N:S ratio can be over-come by providing a mineralsupplement containing sul-phate sulphur or by providingthe sheep with a supplement oforganic sulphur in the form ofexpeller canola meal to supplyextra sulphur amino acids to thesmall intestine.

Successful supplementaryfeeding

A good indicator of the timeto start supplementary feedingis to note when sheep begin toaccess water points towards theend of the pasture growing sea-son. The sheep seeking waterindicates that the pasture isbeginning to dry off and lose itsnutritional value to stock. At thispoint it is important to starttrailing out some lupins (about50 grams per head per day) tomaintain a supply of proteinand non-starch energy to thesheep, especially young sheepthat have a high nutrient

requirement for growth. Youngsheep will not have experiencedlupins before and for them torecognise lupins as a feed it isimportant to start feedinglupins to the lambs with theirmothers before they are weanedThis allows the ewes to teach thelambs all about eating supple-ments of lupins.

As the feed quality dropsoff, it is prudent to increase thesupply of lupins up to about 200

grams per day. Feeding abovethis level of lupins may lead to asubstitution effect whereby thesheep will wait for the nextfeed of lupins rather than goout and eat more of the dry for-age. If weaner growth fallsbelow 100 grams per day theywill need to be moved to a newpaddock with more dry feedavailable, or better quality feed.Young sheep will often require acomplete mineral mix to main-tain good growth rates, particu-larly if the dry feed has hadessential minerals leached outfrom being rained on.

When feeding supplementsto sheep, the goal is to achievethe maximum productionreturns from the minimum costsof feed inputs.An understandingof the special energy and proteinrequirements of the microbialpopulation in the rumen canhelp to achieve this. The mostimportant point to remember isto supply the correct balance andform of protein and energy tothe microbes in the rumen. Inshort, cost effective supplemen-tary feeding of sheep is reallyabout supplying the rumenmicrobes with the nutrients thatare limiting in the basal diet.

All feeds contain somewater and it is important tocompare feeds on a dry-matterbasis to eliminate the differ-ences in water content. To con-vert the energy and proteincontents expressed on a drymatter basis to a fresh or ‘as fed’basis, multiply the energy orprotein value by the dry matterpercentage of the feed anddivide by 100.

The energy content of mostgrains and pulses ranges from10 to 13 megajoules per kilo-gram of dry feed (see Table 2).Lupins provide the highestenergy content. Lupins are par-ticularly good as an energysource because they contain nostarch and will not cause acido-sis.The lower the energy contentof a feed, the more feed thatmust be fed to maintain a sheepor to achieve some growth.

The protein content of a feedcan vary widely with season andfeed-type. In most years oatengrain is relatively low in protein(7 to 10 percent on a dry matterbasis) and will need to besupplemented with lupins tosupply adequate protein forgrowing sheep or lactating ewes.However,a high proportion of thelight oaten grain from the 2000

growing season was high in pro-tein (12 to 16 per cent on a drymatter basis). This allowed manyproducers to reduce, by half, theamount of lupins in the feed mixfed to maintain sheep whichresulted in a big saving becauselupins were in extremely shortsupply and consequently werevery expensive.

Oaten grains can also varyby as much as 1.5 megajoules of





metabolisable energy per kilo-gram of dry matter betweenhigh and low lignin oat varieties.Therefore, it is important tohave feeds tested for energyand protein contents so that youcan be sure the sheep are receiv-ing the correct amount ofenergy and protein for mainte-nance or growth as well as toprovide them with the mostcost-effective diet.

Early-cut hays generallyhave higher energy and proteincontents than later-cut hays (seeTable 3). Legume-based hayshave higher protein contentsthan cereal-based hays. As withgrains and pulses, the proteincontent of hays will vary withthe growing season and agro-nomic practices making itimportant to have hays tested sothat precise feed-rations can becalculated. In most cases cerealhays and late-cut pasture hayswill need to be supplementedwith lupins to provide adequateprotein to growing sheep andlactating ewes.

Generally stubbles andstraws that have low values forprotein and metabolisableenergy are of little nutritionalvalue for sheep apart fromproviding fibre (see Table 4).They will need to be supple-mented with a grain to main-tain adult sheep and certainly togrow out weaners. However,many of the stubbles fromthe 2000 growing season hadhigh values for protein andmetabolisable energy and werea valuable feed resource.

Chaff-cart residues willmaintain adult sheep, but theymay need to be supplemented

Table 2. Grain-based sheep feeds: the dry matter, energy, protein and fibre contents(dry matter basis). The average across the range of values is shown in brackets.

Table 3. Hays fed to sheep: the dry matter, energy, protein and fibre contents (dry mat-ter basis). The average across the range of values is shown in brackets.




Feed grains Dry Metabolisable Crude protein Acid detergentmatter energy fibre

(%) (MJ/kg) (%) (%)

Cereals and PulsesWheat 91 12.4 - 13.3 (12.9) 7.5 - 15.0 (11.5) 2.5 - 4.5 (3.0)

Barley 91 11.6 - 12.2 (11.9) 7.0 - 13.0 (11.0) 7.0 - 9.5 (8.0)

Triticale 90 12.0 - 13.0 (12.5) 7.5 - 14.0 (11.0) 3.5 - 5.0 (4.0)

Oats 92 10.4 - 11.3 (10.7) 5.5 - 13.5 (9.0) 16.0 - 21.5(18.5)

Narrow leaf Lupins 92 13.1 - 14.1 (13.7) 27.0 – 42.0 (34.0) 17.5 – 23.0 (20.0)

Albus Lupins 92 13.4 – 15.0 (14.0) 34.0 – 44.0 (38.0) 17.0 – 21.0 (19.0)

Peas 91 12.5 - 13.5 (13.0) 21.5 - 30.0 (25.5) 6.0 - 10.5 (9.0)

Vetch 91 12.4 - 13.2 (12.8) 26. 0 - 34.5(29.0) 7.5 - 9.5 (8.5)

Chick Peas 91 12.0 - 13.0 (12.4) 18.0 - 24.0 (21.0) 12.0 - 16.0 (14.0)

Faba beans 90 12.4 - 13.2 (12.9) 22.0 - 30.0 (26.0) 7.5 - 9.5 (8.5)

Canola (>35% Oil) 95 15.0 - 17.0 (16.0) 20.0 - 25.0 (22.0) 22.5 - 26.5 (24.0)

Cereal secondsWheat 92 11.8 - 12.4 (12.1) 12.5 - 17.0 (13.5) 3.5 - 5.5 (4.5)

Barley 93 11.1 - 11.8 (11.4) 11.0 - 14.5 (12.5) 9.5 - 12.5 (10.0)

Triticale 92 11.3 - 12.1 (11.7) 10.5 - 15.5 (13.0) 4.5 - 6.5 (5.5)

Oats 93 9.8 - 10.5 (10.3) 4.5 - 16.0 (12.5) 21.0 - 26.0 (23.5)

Sheep pelletsMaintenance 90.0 8.0 - 9.0 (8.5) 8.5 - 9.5 (9.0) 29.5 - 32.0 (31.0)

Production 91.0 10.6 - 11.4 (11.0) 13.5- 16.0 (15.0) 20.0 - 25.0 (23.0)


Hays Dry Metabolisable Crude protein Acid detergentmatter energy fibre

(%) (MJ/kg) (%) (%)

Oatenearly-cut 90 8.8 - 10.2 (9.1) 7.0 - 12.5 (8.5) 25.0 - 32.0 (30.0)

late-cut 90 8.0 - 9.0 (8.5) 4.0 - 7.5 (6.0) 30.0 - 37.5 (32.5)

Wheatenearly-cut 90 9.0 - 10.0 (9.4) 8.0 - 11.5 (9.5) 25.0 - 31.0 (29.0)

late-cut 90 8.0 - 9.0 (8.6) 4.5 - 7.5 (6.5) 30.0 - 36.0 (32.0)

Barleyearly-cut 90 9.0 - 10.0 (9.4) 8.0 - 11.0 (9.2) 25.0 - 31.0 (29.0)

late-cut 90 8.0 - 9.0 (8.6) 4.5- 7.5 (6.5) 30.0 - 36.0 (32.0)

PastureGrass dominantearly-cut 88 9.0 - 10.8 (10.0) 12.0 - 18.0 (14.5) 24.0 - 30.0 (28.0)

late-cut 88 8.0 - 9.5 (9.0) 8.0 - 12.0 (10.0) 30.0 - 34.5 (32.5)

Clover dominantearly-cut 88 9.5 - 11.2 (10.2) 15.0 - 23.0 (17.0) 23.0 - 29.0 (27.5)

late-cut 89 8.5 - 9.8 (9.5) 11.0 - 15.0 (12.5) 30.0 - 33.0 (32.0)

CLIMA legume 89 9.3 - 11.1 (10.2) 14.0 - 20.0 (16.0) 27.0 - 32.0 (29.5)

Cereal/Vetch 88 9.0 - 10.0 (9.5) 10.5 - 15.5 (13.0) 29.5 - 32.0 (31.0)

Pea 88 9.0 - 10.0 (9.5) 13.0 - 17.0 (15.5) 30.0 - 33.0 (31.5)

Lucerneearly-cut 88 9.8 - 10.5 (10.0) 20.0 - 30.0 (26.0) 27.0 - 29.0 (28.0)

late-cut 89 9.0 - 9.8 (9.5) 13.0 - 20.0 (15.0) 30.0 - 33.5 (32.0)



Table 4. Straws and stubbles fed to sheep: the dry matter, energy, protein and fibrecontents (dry matter basis). The average across the range of values is shown in brackets.

Table 5. Chaff-cart residues: the dry matter, energy, protein and fibre contents(dry matter basis). The average across the range of values is shown in brackets.

with additional protein if theprotein content of the dietconsumed falls below sevenper cent. The average contentsof the nutrients in chaff-cartresidues are given in Table 5.

Further readingFarmnote 74/2000.Achieving production targetsfor prime lambs.

Farmnote 35/95.Supplementing weaner sheepgrazed on oat stubbles withsandplain lupin seed.

Farmnote 65/91.Selection of supplementaryfeeds.

Farmnote 79/91.Lupins versus feed blocksfor sheep.

Farmnote 56/89.Hand feeding sheep; add finelyground limestone to grain.

Farmnote 99/85.Boosting nitrogen content ofoats for sheep feed.



Straws/ Dry Metabolisable Crude Acid detergentstubble matter energy protein fibre

(%) (MJ/kg) (%) (%)

Oat 89 6.0 - 7.7 (6.8) 4.0 - 6.5 (5.0) 38.0 - 45.0 (43.0)

Barley 89 6.0 - 7.5 (6.7) 4.0 - 6.5 (5.0) 38.0 - 47.0 (44.0)

Wheat 91 5.8 - 7.0 (6.5) 2.5 - 6.5 (3.5) 43.0 - 52.0 (47.0)

Triticale 89 5.5 - 7.0 (6.3) 2.5 - 6.0 (3.5) 44.0 - 52.0 (48.0)

Lupin 92 5.5 - 9.5 (8.0) 6.0 - 10.0 (8.0) 36.0 - 44.0 (42.0)

Pea 90 6.5 - 7.8 (7.2) 6.0 - 8.5 (7.5) 38.0 - 44.0 (42.5)

Canola 92 5.5 - 7.5 (6.5) 4.0 - 7.5 (6.0) 42.0 - 50.0 (47.0)

Sorghum 88 5.5 - 7.0 (6.5) 3.5 - 6.0 (4.5) 45.0 - 54.0 (48.0)

Chaff-cart Dry Metabolisable Crude Acid detergentresidues matter energy protein fibre

(%) (MJ/kg) (%) (%)

Oat 90 6.5 - 8.0 (7.2) 5.0 - 7.0 (6.0) 36.0 - 44.0 (41.0)

Barley 90 6.5 - 8.2 (7.5) 5.0 - 7.5 (6.5) 37.0 - 45.0 (42.0)

Wheat 90 6.2 - 8.5 (7.5) 4.5 - 8.0 (6.5) 39.0 - 50.0 (45.0)

Canola 92 6.0 - 8.5 (7.5) 5.0 - 9.5 (7.5) 42.0 - 50.0 (45.0)

Lupin 92 7.5 - 9.5 (8.5) 7.5 - 11.5 (9.5) 35.0 - 43.0 (41.0)

L o t- Fe e d i n g P R I M E L A M B SJohn Milton, Department of Agriculture, based at

The University of Western Australia, Nedlands


L o t- Fe e d i n g P R I M E L A M B S

Lot-feeding prime lambsLot-feeding can be defined

as feeding animals in a confinedarea with all required nutrientsbeing brought to the animals.The area available to the ani-mals is generally small so thattheir movement is restricted tominimise energy expenditure.Good quality water must beavailable for the animals and itis preferable to also providethem with shade and protectionfrom inclement weather.

Lot-feeding prime lambs inWestern Australia is often anopportunistic and value-addingactivity with the objective tobring unfinished lambs up tomarket specifications whenthere is a shortage of qualitypaddock feed. Some lot-feedersoperate year-round as special-ists and they may house thelambs in sheds, mainly toprovide protection from coldrainy weather.

Factors to consider whensetting up a feedlotSite of the feedlot

Feedlots can generate dustand smells, and water run-offfrom a feedlot may pollutewaterways. Consideration mustbe given to the location of thefeedlot in relation to water-courses, public roads andhouses. Use natural vegetat-ion wherever possible toprovide lambs with shadeand shelter from wind andinclement weather. However,the vegetation will also need tobe protected from damage bythe lambs.

Soil type and slope are alsoimportant factors. Sandy soilsmay drain well, but can be proneto wind erosion if the surfacebecomes bare and the soil is dis-turbed. Heavy soils are lessprone to wind erosion, but maybecome muddy when wet andthis can lead to the spread offootrot, foot abscesses, salmo-nellosis and coccidiosis. A goodslope aids drainage, but if toosteep the site may be predis-posed to water erosion. It canbe beneficial to establish thefeedlot on the north or north east side of a hill ormound so the site gets maxi-mum sun in winter.

Water availability and quality

To maximise feed intake,lambs must have an adequatesupply of cool, clean waterwith a maximum of 5000 partsper million of total dissolvedsalts (approximately 900

milliSiemens per metre). If thetotal dissolved salts in the wateris above 1000 parts per million itis wise to have the wateranalysed so the level of mineralsadded in the diet can beadjusted if necessary. Allow atleast four litres of water perlamb per day when calculatingdaily water demand and provideat least 75 centimetres of watertrough length per l00 lambs onfeed. Inadequate space at thewater trough, high salt levels, orcontamination of water withalgae, feed, dust or faeces canresult in reduced water intake,and consequently reduced feedintake and lamb performance.

Area per lamb

The area allocated per ani-mal will vary with the type offeedlot. In a confined, indoor set-up it can range from 0.5 to twosquare metres per lamb. In smallpaddocks the area needs to besmall enough to prevent thelambs chasing ‘green pick’thereby wasting energy, butlarge enough to prevent boggyconditions when it rains. It maybe an advantage to have a largerarea available when the lambsfirst enter the feedlot, and tosubsequently reduce the area toprevent the generation of dust.However, if the area is too largewhen the lambs first go into thefeedlot some may hang-backand be slow to eat from thefeeders. Generally an area ofabout 0.5 square metres perlamb is adequate for mobs of upto 500 lambs.

Mob size

A maximum of 500 lambsper mob with mobs of 300 to400 is preferred for ease ofmanagement. It is often wise todraft lambs into mobs based onsex, size, condition or similarfeed history.

Feeding systems

The choice of feeding sys-tem is influenced by commit-ment, cost and convenience.

Complete mixed rations canbe fed once or twice a day inopen troughs. This is a morelabour-intensive option. Theration is generally quite bulkybecause roughage (hay or silage)is mixed with the grain. Thissystem gives good control of



the diet consumed, but a mixer(Mixall) or feed wagon is requ-ired to mix the grain and feed-out the ration.

Lambs generally needabout 25 centimetres of troughspace per lamb with open feedtroughs. It is important thattroughs be adequately pro-tected so that lambs can not getin the troughs and foul the feed.

Various options to providefeed at all times are availableand include:ó Ad libitum access to a

complete mix of grain,milled roughage, mineralsand vitamins.

ó Ad libitum on a grain, min-eral and vitamin mix or pel-let in feeders and roughagein separate troughs.

ó Ad libitum access to a pelletration of grains/roughage/minerals and vitamins.

Self-feeders are convenient,reduce the need for regularfeeding and require less troughspace per lamb with ad libitumaccess (only four to five centime-

tres per lamb). Lambs go ontothe feed quicker if there is plentyof space and if space is inade-quate there may be a ‘tail’ oflambs because of shy feeders.Round feeders allow betteraccess than straight troughs.

With the first option listedabove the hay or stubble has tobe milled to mix it with thegrain. This requires specialmachinery and can be labourintensive. There can also beproblems with the ration ‘bridg-ing’ and the sheep may selec-tively eat the grain from themix. Silage can not be fed inthis system.

The second option requiresonly basic equipment to mix thegrain with a mineral/vitaminpre-mix and deliver the mix orpellets to the feeders. Hay orsilage can be put in racks or thebales rolled out. With thisoption, the lambs have a choiceand may eat different propor-tions of the grain mix, pellet orroughage. This ability to choosetheir diet can affect growthrates and may result in acidosisif the lambs do not eat adequateroughage. The roughage, espe-cially hay, must be protectedfrom rain to avoid it getting wetand being rejected by the lambs.

The third option of using aformulated pellet is a conve-nient way to provide a completediet. It may be beneficial if thepellet contains some long fibreto maintain good rumen func-tion. There is a cost for pelleting,but as well as being convenient,appropriate pellets may allowrapid introduction and goodgrowth from day one.

Finishing in small paddocks

Hay or silage can be fed adlibitum with a grain trail offeredtwo or three times per week.Conveyor belting makes a handytrough to feed silage. Gutteringcan be used as a trough to feedgrain. It may be possible to feedsilage ad libitum from a clampwith grain offered two or threetimes per week. The amount ofgrain fed is used as the ‘throttle’to control the lambs’ growthrate. These cheap feeding sys-tems can be used to achievemodest growth of 50 grams perhead per day for carryover lambsthrough to higher growth ratesof 175 grams per head per day tofinish lambs for slaughter.

Lupins can be trail-fed onclean, hard ground. However,there is likely to be somewastage with cereal grains inwet weather and these grainsare best fed in a simple troughor guttering.

In a production situation, itis possible that the minerallevels in roughage and grainmay be marginal or deficientfor maximum growth rates.Minerals with or without canolameal can be fed ‘free-choice’, ormixed with the grain.

Ration considerationsIntroducing high grain diets

There is always some risk ofacidosis when lambs are fedhigh grain diets, so these rationsmust be introduced carefully.Even minor acidosis can result inserious losses. Apart from theloss of animals, time and grain,there may also be a lengthyrecovery for some animals. This

Carryover lambs in an indoor feedlot atDonnybrook.

can set back the program a num-ber of weeks and you may miss acontract or prices may havefallen by the time the lambs aresuitable for slaughter.

The risk of acidosis can beminimised by ensuring thelambs are adapted to the highgrain diet and that they con-sume enough roughage to stim-ulate ‘chewing the cud’. Thefollowing practices will reducethe incidence of acidosis:

ó Gradually switch from a highroughage to a high graindiet over ten to 14 days andkeep adequate roughage inthe ration. Growth duringthis introductory period isoften slow.

ó Start with a high percentageof lupins and roughage andgradually raise the percent-age of cereal grain andreduce the lupins androughage to the desiredlevel. (This may allow goodgrowth from day one).

ó Whole cereal grain is lesslikely to cause acidosis thanmilled grain. Milling or pro-cessing the cereal grain com-ponent of rations provides lit-tle if any nutritional benefit tolambs and generally increasesthe risk of acidosis. However,coarse milling of lupins mayhelp deter lambs from select-ing out this grain from otherration components.

Some producers incorpo-rate additives with the grains fedto lambs to reduce the chance ofthe animals developing acidosisor at least to reduce the severityof acidosis. These products and

compounds include ground lime-stone (calcium carbonate), ben-tonite, and sodium bicarbonate.

For further advice on theuse of additives with grainrations contact your consultantor local office of Department ofAgriculture.

As discussed in an earliersection of this bulletin, the mainnutrients to be supplied inrations are:

ó Crude protein expressed as apercentage of the total drymatter. The protein levelrequired in the diet dependson the liveweight of thelambs to be fed and theirpotential for muscle growth.The level of crude proteinrequired is usually in therange of 14 to 16 per cent.

ó Metabolisable energy expr-essed as megajoules ofmetabolisable energy perkilogram of dry matter. Thedietary requirement formetabolisable energy isinfluenced by lamb live-weight and the desiredgrowth rate and the poten-tial intake of the ration to befed. Usually it is in the rangeof 10.5 to 12.0 megajoulesper kilogram of dry matter.

ó Minerals both major (gramsper kilogram) and minor (mil-ligrams per kilogram) mustbe adequate to support highgrowth rates as deficiencieswill limit performance.

ó The body stores of vitaminsA and E may be low if lambshave been off green feedfor more than a few months.Backward lambs may needto be injected with vitamin

B12 on entry to the feedlot.Lambs fed indoors mayneed vitamin D and vitaminB1 deficiency may be aproblem with diets thatdo not encourage goodrumen function.It is essential to know the

nutrient content of the availablefeeds. There is a wide variationin crude protein and metabolis-able energy between feeds andwithin feeds between years.Season, fertiliser inputs, varietyand yield all influence the levelof protein and energy in feeds.

It is recommended thatfeeds be analysed for dry matter,crude protein and energy con-tent so that a ration can be for-mulated to meet the nutrientrequirements that will achievethe desired growth rate anddegree of fattening. Feed analy-sis information can also be usedto compare different feedsbased on their cost per unit ofcrude protein and metabolis-able energy.



Lambs in an outdoor feedlot at Williamswith large square bales providing shelterfrom the wind.



EconomicsIt is important to do an eco-

nomic analysis before startingto feed. The economics of lot-feeding relies on the cost toeffectively combine feedstuffs tosupply all the nutrients requiredfor optimum lamb growth andto achieve carcases with meat ofdesirable eating quality.

ó Know the buy-in price oflambs (put a value on yourown lambs).

ó It is preferable to have asigned contract with anagreed sale price for lambs.

ó Estimate the ratio of feedintake to liveweight gain(feed conversion ratio).

ó If possible, know the geneticability of the lambs fed(potential growth rate andfatness).

Calculate the costs per kilo-gram of weight gain, including:ó The cost of capital items

used for lot-feeding.ó Feed stuffs (realistically value

your own feed ingredients).ó Labour.ó Health and management

costs.ó Lambs fed that are unlikely

to finish (this may be up to20 per cent).Performance indicators for

35 kilogram lambs finishing at45 kilogram liveweight are:

1st cross lambs:

ó Growth rates of 250 to350 grams per head perday. Feed conversion ratios of7:1 to 5.5:1 for rations ofabout 90 per cent dry matter.

Merino lambs:

ó Growth rates of 220 to320 grams per head perday. Feed conversion ratios of7.5:1 to 6:1 for rations ofabout 90 per cent dry matter.

Healthó Drench on entry to the feed-

lot with an effective broad-spectrum drench.

ó Control lice - they affectperformance and can causecotting of fleeces.

ó Vaccinate with 3:1 or 6:1(with or without seleniumand Vitamin B12) to controlClostridial diseases, espe-cially enterotoxaemia orpulpy kidney that isfavoured by diets high instarch. Selenium can bedeficient in many areas ofWestern Australia and canbe administered in drenchesas well as with vaccines.

ó Inject vitamins A, D and E ifthe lambs have been offgreen feed for more thantwo months and these vita-mins are not being suppliedas a pre-mix. Low vitamin Elevels must be correctedwith the use of a powderedformulation, either as adrench or mixed with grain.

ó Inject with vitamin B12 iflambs are low in conditionon entry to the feedlot.

ó Avoid feeding lambs affe-cted by lupinosis, especiallythose showing signs ofjaundice.

ó Urinary calculi (water belly)can occur in lambs fed grainrations for prolonged peri-ods, especially wethers. Addcalcium to the ration to cor-

rect the calcium to phospho-rus imbalance from cerealgrain and ensure there isadequate roughage so thatlambs ‘chew the cud’. Finelyground limestone is probablythe best source of calcium,but gypsum can also be used.

ó Check for grass seeds in theskin and/or eyes.

ó Pink eye - reduce dust andremove infected lambs.Provide good access to feedand water, especially iflambs are blind.

ó Scabby mouth - avoid abra-sive roughages. The virus canquickly spread to manylambs,but mortality is gener-ally low. Feed intake is proba-bly affected with severelesions on the lips causing areduction in growth rates. Avaccine against the disease isavailable and is now widelyused in Western Australia.Animals with an unknownvaccination history shouldbe vaccinated before entry toa feedlot.

ó Coccidiosis - caused by over-crowded, unhygienic condi-tions and faecal contamina-tion of feed, especially in wetweather. The problem is pre-cipitated by stress andinfected lambs may remainpoor doers. Lasalocid is regis-tered for use in sheep dietsand is effective for the con-trol of coccidiosis.

ó Pneumonia - is a bacterialinfection aggravated bydust and cold stress. Thedisorder can be treated withantibiotics, but it is impor-tant to adhere to withhold-ing periods.

Husbandry/managementó Weigh and fat score lambs to

monitor growth and to checkthat they are on target forthe proposed slaughter date.Adjust the rations if neces-sary to keep lambs on targetto meet specifications.

ó Only send those lambs forslaughter that will meet thespecifications. Fat score,weigh and make an assess-ment of the likely dressingpercentage after allowingfor the factors that affectdressing percentage; timeoff feed, length of wool, fatscore and transport stress.

ó Woolly lambs are best shornon entry to the feedlot, butconsider their skin value atslaughter. Shearing raisesfeed intake in warm weatherand can improve growthrate. Shorn lambs need lessfeed space, are less prone tofly strike but are very proneto cold stress.

ó With large numbers oflambs, separate the ewesfrom wethers to facilitatemonitoring so that the ewesin particular do not get toofat. It may be necessary tofeed ewes and wethersdifferent diets if ewes areto be lot-fed to produceheavy carcases.

ó Sick lambs are best removedfrom the feedlot.

ó Shy feeders need to bedrafted off early and fedseparately or put out onpasture.

ó Minimise stress; dogs mustnot be allowed to annoylambs. Handle lambs care-fully at all times.

ó If feeding-out a completemixed ration, feed at thesame time each day and bythe same routine. Keep self-feeders full at all times oncethe lambs have adapted tothe ration.

ó Be vigilant for things goingwrong, for example, dirtywater troughs, fly strike,lambs not ‘chewing the cud’,lambs scouring, lambs noteating roughage or selectingout individual components ofthe ration. Problems canquickly turn into financial dis-asters with lambs underintensive management, soattention to detail is essential.

Welfare and safefood issues

Follow best practices, keeprecords of all health and hus-bandry practices. Follow with-holding periods for drenches,chemicals and antibiotics. Cleanup daggy lambs and allowlambs to empty-out for at least8 hours, preferably on grating,before trucking.

Further readingFarmnote 72/2000.Sheep health in a feedlot.

Farmnote 73/2000.Lot-feeding prime lambs.

Farmnote 74/2000.Achieving production targetsfor prime lambs.

Farmnote 25/99.Preparation and assessment ofsheep and lambs for slaughter.

Maximum meat: the completeguide to producing qualitysheep meat. Department ofAgriculture. 1998



Fe e d i n g fo r M E AT CO L O U RRobin Jacob and Graham Gardner,

Murdoch University, Murdoch.


Fe e d i n g fo r M E AT CO LO U R

K E Y M E S S AG E Só Meat with a pH above 5.7 tends to be darker than that desired by consumers and

has poorer keeping and eating qualities than meat with a pH below 5.7.ó Meat pH is determined by the amount of muscle sugar (glycogen) in the muscle

when the animal is slaughtered.ó High-energy diets (above 11 megajoules metabolisable energy per kilogram)

before slaughter will increase reserves of muscle sugar and help to maintain good meat colour.

ó Stressful activities such as handling or transport will deplete reserves of muscle sugar.

ó Merino sheep tend to be more susceptible to stress than British breeds or cross breds.

ó Magnesium oxide supplements (one per cent for four days before slaughter) will reduce the stress response.

The Significance ofMeat Colour

Colour is a key issue in theeating quality of meat. Thetrade discounts dark cuttingmeat, as consumers prefer meatto be “cherry red”. Dark cuttingmeat:ó is less visually attractive to

consumers;ó takes longer to “bloom” on

exposure to air;ó is tougher;ó has poorer keeping qualities;ó takes longer to cook;ó has a stronger flavour, andó yields less.

Acidity determines colourAcidity interacts with the

pigments in meat and is a majordeterminant of meat colour.Acidity is measured by pH. Ifmeat has a pH greater than 5.7it tends to be dark and have theproperties listed above.

Muscle sugars determineacidity

Meat acidity depends onthe amount of lactic acid formedfrom muscle sugar (glycogen)after the animal is slaughtered.High sugar levels before slaugh-ter result in a low pH, around5.5, and desirable colour.

Nutrition and stress are thekey determinants of musclesugar. Nutrition can fill the

glycogen reserves similar tofilling a bucket, while stresscan drain glycogen reserves asholes would drain a bucket.Merino sheep are more suscepti-ble to dark cutting than Britishbreeds and crossbred sheepbecause of their increased sus-ceptibility to stress.

Finish on highenergy diets

Feeding high-energy dietsof around 11 megajoules ofmetabolisable energy per kilo-gram will increase stores ofmuscle glycogen. Grain-baseddiets are generally required toachieve this level of energy.However, research has shownthat high energy feeding is onlyrequired for seven days toincrease muscle sugar.



In practice, 14 days is rec-ommended to allow safe intro-duction to grain diets and toensure that all animals in agroup are eating the diet. Inother words, sheep that reachmarketable weight and fatscore ranges on low-energy pad-dock diets, will require a finaltwo-week grain-based feedingprogram to ensure desirablemeat colour.

Shearing and FeedingFeeding is especially impor-

tant for sheep shorn within fourweeks of slaughter and exposedto cold or wet conditions.Without the insulating proper-ties of their fleece, sheepexposed to cold conditions willdraw on energy reserves to bal-ance energy requirements. Thiscan have a direct effect on mus-cle sugar if dietary energy is lim-iting. If sheep are fed high-energy diets after shearing theycan compensate to the pointwhere stores of muscle sugar areunaffected by cold. Again, feed-ing need only be for two weeksbefore slaughter.

Feed additives toprevent stress

Adding magnesium oxideto the diet at a rate of one percent (10 kilograms per tonne)for four days before slaughter,can reduce the losses ofmuscle sugar caused by thestress of transport and lairage.

Magnesium blocks theeffects of adrenaline and there-fore prevents stress from caus-ing muscles to use up storedsugar. However, it should not beadded to diets for longer thanfour days as the effect wears offwhen it is fed for longer. Also,adding magnesium is not asimportant as the energy in thediet that will ensure sheep startwith high stores of muscleglycogen before they leave thefarm for the abattoir.



TROUGH OFMUSCLE

GLYCOGEN

NUTRITION

THISSTRESS

THATSTRESS

TRANSPORTSTRESS

HANDLINGSTRESS

Figure 1: Nutrition fills the glycogen bucket and stress can empty it.

S h e e p H E A LT H I S S U E SDon Moir, Department of Agriculture, Narrogin


S h e e p H E A LT H I S S U E S

A few of the most commonconditions affecting sheep usedfor meat production are consid-ered briefly. For more detailedinformation, readers shouldconsult their private veterinar-ian or consultant.

Enterotoxaemia(Pulpy Kidney)

This is a disease caused bychanging diets from low to highquality feeds as occurs withgrain feeding, or moving sheeponto crop stubbles or goodgreen feed. It also may be seenin lambs suckling ewes on lushgreen feed.

This disease is most oftenseen in lambs and weaners butcan affect sheep of any age.

Signs

ó Sudden death. Sheep areusually found dead withoutany symptoms having beenobserved.

ó The head may be thrownback, and there can be con-vulsions.

ó There can be frothing atmouth.

Control

ó This is by a vaccination givento lambs at marking andweaning, and annuallythereafter. Ewes are given anannual booster four weeksbefore lambing to protectthe lamb for the first sixweeks of life.

ArthritisThis is a common condition

in lambs after marking, or lessoften in the first four weeks oflife. It is caused by the entry ofbacteria into the body via mark-ing wounds or the umbilicalcord in newborn animals.

Arthritis is due to a highenvironmental contaminationwith specific bacteria (Erysipelas,Streptococcus,Haemophilus) thatbuild up in sheep yards andunder conditions of high stock-ing densities.

Signs

ó Hot painful swelling of oneor more joints in the legs.Lambs are lame, reluctant towalk, and become ill thrifty.They may die through poormothering.

Control

ó Carry out marking andmulesing in temporaryyards in a clean paddock.Ensure the use of hygienicmeasures with clean instru-ments. Clean the woundsand change disinfectantsolutions often. Wash bloodfrom hands often.

ó For persistent problems con-sider the options of vaccina-

tion or prophylactic treat-ment with your veterinaryconsultant.

More information aboutthis problem is available in theFarmnote 4/94, Sheep Arthritis.

Internal Parasitesi) Worms of sheep are a

major cause of economic lossdue to mortalities, ill thrift,reduced wool growth and scour-ing with subsequent fly controlmeasures (crutching, jetting,strike treatment). Also, they cancontribute to other conditionssuch as nutritional ill thrift ofweaners and pregnancy tox-aemia. Sub clinical productionlosses occur without the pro-ducer’s knowledge.

The widespread incidenceof resistance to drench chemi-cals has made control programsmore complex.

Signs

ó These may be sub clinical,that is, no obvious signs.

ó There can be various combi-nations of ill thrift, anaemia,scouring and death.

Control

ó Biannual test for drenchresistance.

ó Use a control program thatincorporates paddock andstock management, wormegg count monitoring,chemical rotation and adrenching strategy.

ó Prime lambs may need to bedrenched on a lower wormegg count than is used for

Hock joint swollen with arthritis.



other lambs to maintainmaximum growth rates.

ii) Coccidiosis. This is causedby a protozoan parasite of thesmall intestine that is present invirtually all sheep flocks. It isnormally present in sheep insmall numbers and causes noharm. However, when seasonalconditions result in poor condi-tioned ewes with reduced milkproduction, lambs are forced tograze pasture at an earlier ageand to a greater degree thannormal and this results in anincreased intake of coccidia.Increased intakes of the parasitein lambs can also occur inhand feeding situations wherepatches of ground becomeheavily contaminated.

The condition is usually seenin lambs up to eight weeks of age.Most of the lambs will self-cureand then become immune.

Signs

ó A dark scour, sometimes con-taining blood.

ó Lambs are unthrifty, anaemicwith a low mortality rate,except where poor nutritioncontinues.

Control

ó Supplementary feeding ofthe ewes.

ó Change the trail-feeding siteregularly.

ó Affected prime lambs can betreated (consult a veterinarypractitioner).

Scabby MouthThis disease is also known

as contagious ecthyma or Orf. Itis caused by a virus that can livefor years in the environment.

Scabby mouth is importantbecause it is a threat to the via-bility of the live sheep trade, butit can also cause economic lossof condition in young sheep dur-ing outbreaks on farms. Thevirus gains entry through skindamage to the mouth that canbe caused by thistles and stub-ble or via damage to the feetcaused by long, wet grass.

The disease can cause skinlesions in humans.

Signs

ó Scabs develop around themouth, above the hoof or lesscommonly on the udder ofewes and scrotum of rams.

ó Animals may have difficultyeating or walking withsubsequent loss of condi-tion. Self-cure takes three tofour weeks.

Control

ó Vaccinate lambs at marking.It is important that allsheep to be exported havebeen vaccinated.

There is more informationabout this problem in theFarmnote 19/97, Scabby Mouth.

Acidosis (Grain poisoning)This is caused when sheep

are introduced too quickly todiets high in grain. It also is seenwhen self-feeders run out of

grain for several days and arethen refilled with a consequentengorgement by sheep.

Signs

ó Scouring, rapid breathing,inappetance, depression.

ó Occasionally lameness,bloating.

ó Death in severe cases.

Control

ó Introduce sheep to grainfeeding gradually over atwo-week period.

BloatThis is not a common prob-

lem in sheep. However, it mayoccur on young, rapidly growinglegumes such as lucerne orclover. It is caused by froth form-ing in the rumen, which pre-vents the animal from belching.

Signs

ó Swelling of the left flank.ó Discomfort, rapid breathingó Sheep get up and lie down

frequently. They may col-lapse and die in severe cases.

Control

ó Treat affected animals witha drench of 40 millilitres ofparaffin or any vegetable oilfor short-term control.

ó Restrict grazing time on dan-gerous pastures.

ó Provide access to hay.ó Strip graze.



LupinosisThis is a disease caused by

consumption of the toxic pho-mopsins that are produced by afungus that colonises lupinplants. Although the fungusinfects the plant while it is grow-ing, it only produces enough ofthe toxin to produce lupinosisafter the plant has died and hassubsequently been exposed torainfall or heavy dews. For thisreason lupinosis is usually a dis-ease seen in summer andautumn when sheep are grazedon lupin stubbles.

In the feedlot, lupinosis mayalso occasionally result from thefeeding of crop fines collectedwhen harvesting lupins, or thefeeding of lupin seconds con-taining large proportions of dis-coloured seeds.

The phomopsins primarilydamage the liver, so the clinicalsigns are usually related to liverdisease. However, in younggrowing sheep the liver damagemay also cause altered metabo-lism of selenium and vitamin E,resulting in the development oflupinosis-associated myopathy,a disease similar to white muscledisease or nutritional myopathy.

Signs

ó These may vary greatlydepending on how muchtoxin is consumed. Feedintake may be reduced, orthere may be a complete lossof appetite.

ó Sheep may not put onweight in a situation whenthey should, or there may beobvious loss of weight andcondition.

ó As the disease progressesthere will be lethargy, wan-dering and “star gazing”,jaundice, depression anddeath.

Control

ó Plant only Phomopsis-resis-tant lupin cultivars.

ó Observe sheep regularlywhile grazing lupin stubblesor stands of sandplain lupinsduring summer andautumn. If they are notgrowing as well as might beexpected, always suspectlupinosis and move thesheep to non-lupin pasture.

ó Do not feed lupin seed tosheep suspected of havinglupinosis; their livers cannothandle the high protein dietand they develop ammoniatoxicity.

ó Sheep should be removedfrom lupin stubbles at least aweek before going to theabattoir. Some may haveinternal jaundice associatedwith subclinical lupinosis,and their carcases will berejected.The one-week breakfrom lupins is usually suffi-cient to allow the jaundiceto resolve.

ó Ensure that young sheepgrazed on lupin stubbleshave adequate selenium andvitamin E.

Pregnancy ToxaemiaThis is caused by an inade-

quate intake of energy duringlate pregnancy and is exacer-bated by ewes having multiplefoetuses. It may be induced by asudden cessation of eating

caused by adverse weather, orthe moving or yarding of flocks.Over-fat ewes are most prone tothe problem. It can also result inthe birth of dead lambs.

Signs

ó A loss of appetite.ó Sheep become separated,

depressed and wander aim-lessly.

ó They appear blind,ignore dogsand people, become recum-bent, comatose, and die.

Control

ó Monitor the condition ofpregnant ewes by weighingand/or condition scoring.

ó Be prepared to supplemen-tary feed pregnant ewes.

ó Pregnancy-test high multi-ple birth flocks and feedaccording to their pregnancystatus.

Cheesy GlandAlso known as yolk boils,

abscess and caseous lym-phadenitis (CLA). The bacteriumCorynebacterium pseudotuber-culosis causes abscesses to formin lymph nodes and lungs ofsheep and goats, leading tolosses in wool production, car-case condemnation or trimmingat abattoirs and some mortali-ties. Spread is commonly associ-ated with shearing and dipping.

Signs

ó Abscess formation underskin or internally.

ó Pus is light green to creamcolour.



ó Occasional death in adultsfor no obvious reason.

Control

ó Vaccinate lambs at markingand weaning. Yearly boost-ers before shearing areessential to lower flockprevalence.

ó Minimise the time sheep arekept in close contact aftershearing.

ó Avoid dipping sheep if no liceare present.

Pink EyeA bacterial infection of one

or both eyes. It is aggravated bycongregation in dusty condi-tions and irritation by flies.Most sheep recover from pinkeye. However, up to four per centmay become permanentlyaffected if left untreated. Thisproblem may be confused withgrass seeds in eyes.

Signs

ó Inflammation and tearsfrom affected eyes.

ó Cornea becomes red thenwhite as condition pro-gresses.

Control

ó Avoid yarding during out-break. If necessary, draft-offaffected animals and isolatethem.

ó Treat with antibiotic eyeointment.

PneumoniaCaused by a variety of bac-

teria. Pneumonia is most com-monly seen in young sheep ondry, dusty feeds. Irritation fromdust allows bacteria to invadeand cause inflammation andinfection.

Signs

ó Nasal discharge, coughing,high temperature andlethargy.

Control

ó Avoid finely hammer-milledfeeds.

ó Dampen feed or add a dustsuppressant, for example,tallow.

ó Treatment of clinical casesmay require antibiotic treat-ment as advised by a veteri-narian, with strict adherenceto withholding times.

SalmonellosisContamination of feed or

water sources with faecal mate-rial can lead to infection withsalmonella bacteria. Trail-feed-ing grain in the same area canlead to a build up of faeces andresult in disease, especially ifsheep are under nutritionalstress or subject to adverseweather. Summer storms maywash large quantities of faecesinto water supplies leading tosalmonellosis.

Signs

ó Scouring, high temperature,lethargy, death.

ó Abortion in pregnant ewes.

Control

ó Prevent faecal contamina-tion of feed and water.

ó Change trail-feeding sitesregularly.

ó Withhold sheep fromaffected mobs from slaugh-ter until the outbreak is over.

HydatidsHydatid disease is caused

by the tapeworm Echinococcusgranulosus which lives in theintestines of dogs, foxes and din-goes. The tapeworm eggs passonto the ground in the dog fae-ces where they may be ingestedby grazing animals. These eggsthen develop into multiple cystswithin the liver and lungs andwill result in condemnation ofthe carcase at abattoirs.

Hydatid disease is a majorhuman health hazard. Dogtapeworm eggs ingested by

Cheesy gland abscess in the hindleg of amutton carcase.



humans develop into cysts thatcan only be treated surgically.

Signs

ó Infected sheep show noexternal symptoms.

ó Autopsy reveals multiplefluid-filled cysts in the liver,lung and occasionally thebrain.

ó Dogs infected with E. granu-losus show no signs of aproblem.

Control

ó Treat dogs every two monthswith the drug praziquantel.

ó Do not feed dogs raw meator offal. Prevent access toany carcases on the farm(including kangaroo, wallabyand pig). Burn carcases assoon as possible.

ó Control fox and dingo popu-lations.

Sheep MeaslesAs with hydatid disease,

sheep measles is the intermedi-ate stage of a dog and fox tape-worm called Taenia ovis. Eggs onpastures picked up by sheepdevelop into small cysts in themuscles and heart. Old cystsbecome hard, fibrous and some-times gritty, and are known as“measles”. Infected carcases arerejected at abattoirs.

Signs

Severe infection may causeproduction losses.

ó There are no other externalsigns of infection in sheep.

ó Carcases show small cysts inthe heart, diaphragm andmeat.

ó Dogs infected with T. ovismay pass segments in faecesresembling grains of rice.

Control

ó As for hydatid disease.

Annual Ryegrass ToxicitySeed heads of annual rye-

grass infected with the nema-tode Anguina funesta andthe associated bacteriumClavibacter, become toxic to live-stock. The danger period startsafter flowering in spring andlasts while infected headsremain in the paddock. Theinfection can be transferred tonew areas by contaminatedmachinery and hay.

Signs

Disturbance of the nervoussystem. Collapse, convulsing andthen apparent recovery after dri-ving is common. Animals mayhave a stiff-legged gait.

ó Seriously affected sheep willremain down until they die.

ó Pregnant ewes may abort.ó Mild cases can recover with

rest.

Control

Use of the twist fungus onpastures.

ó Reduce reliance on annualryegrass as major pasturespecies.

ó Seed set control in earlyspring by heavy grazing orchemical application.

ó Autumn burn of affectedpaddocks.

Other disease conditionsOther common conditions

that can affect lambs includetrace element deficiencies,weaner ill-thrift, perennial rye-grass staggers, toxic algae,hypocalcaemia, hypothermia,foot abscess, Eperythrozoonosis(E. Ovis) and photosensitivity.

Water requirementsThe provision of adequate

supplies of good quality water isimportant. The consumption ofwater increases as the concen-tration of salt in the waterincreases. Therefore, it is essen-tial to monitor the quality of thewater and to ensure that thesupply can meet the expecteddemand.

Lambs can only toleratewater with about half the totalsalts that can be used by adultsheep (1100 compared to 1650 to2200 milliSiemens per metre).

Weaners grazed on feedswith a high content of soluble-protein during summer, candrink large quantities of water(up to 9 litres per head per day).Grown sheep can drink evenmore water than this. This rein-forces the need to have a plenti-ful supply of good quality waterfor sheep grazed on these feeds.

Similarly, supplementary-fed sheep need a good supply ofwater.

I N F O R M AT I O N



Pastures

Farmnote 1/99. Puccinellia: forproductive saltland pastures.

Farmnote 26/99. Establishingbalansa and persian clovers onwaterlogged, mildly saline soils.

Farmnote 98/99. Fodder con-servation as silage.

Farmnote 4/98. Drylandlucerne: establishment andmanagement.

Farmnote 11/98. Well-adaptedperennial grasses for the Esperancesandplain.

Farmnote 76/96. Harvestingbalansa clover for seed.

Miscellaneous Publication3/2000. Pasture Growth Rates onFarms in the south of WesternAustralia (2000). Department ofAgriculture.

Miscellaneous Publication2/98. Perennial grasses for animalproduction in the high rainfallareas of Western Australia.K. Greathead, P. Sanford andL. Cransberg (1998). Department ofAgriculture.

Woolprose. Department ofAgriculture, Albany.

Pasture Update. Departmentof Agriculture, Albany.

Ovine Observer. Department ofAgriculture, Narrogin.

Pasture Plus. Kondinin Group,Belmont WA.

Farming Ahead. KondininGroup, Belmont WA.

TIMERITE®, the Kondinin Groupcan provide information on thispackage.

Lot-feeding and drought feeding

Farmnote 72/2000. Sheephealth in a feedlot.

Farmnote 73/2000. Lotfeedingprime lambs.

Farmnote 74/2000. Achievingproduction targets for prime lambs.

Bulletin 2/94. Feeding sheep,including lot feeding and droughtmanagement (1997). PrimaryIndustries and Resources, SouthAustralia.

Health and Welfare Issues

Bulletin No. 4345. ControllingSheep Meat Disorders (1997).Department of Agriculture.

Miscellaneous Publication No.16/90. Code of practice for thewelfare of animals No.4 Sheep(1991). Department of Agriculture,Western Australia.

Miscellaneous Publication No.19/87. Code of practice for thewelfare of animals No. 3 Roadtransport of livestock (1987).Department of Agriculture,Western Australia.

Market Information

Farmnote 25/99. Preparationand assessment of sheep and lambsfor slaughter.

Production and marketing oflarge lean lambs (1995). AustralianMeat and Livestock Corporation.Compiled by Laurie Thatcher

Processing of large lean lambs(1996). Meat Research Corporation.Compiled by David Hopkins.

Marketing lambs over thehooks, a step by step guide (1999).Victorian Department of NaturalResources and Environment.Editor Kristy Howard.

2000 Lamb Survey (2000).Market Information Services, Meatand Livestock Australia.

OUTLOOK - AGWEST Trade andMarket Development QuarterlyNewsletter for Western Australia’sAgribusiness Industry. To requestthe newsletter telephone 08 9322

7141, or Fax 08 9322 7150.

LiveWire – AGWEST Trade andMarket Development WA LiveExport Quarterly Newsletter. Torequest the newsletter telephone08 9322 6141, or Fax 08 9322 7150.

Easton, W.S. (1994). Opportunitylot-feeding of lambs. AgricultureVictoria, Swan Hill.

Reproduction

Farmnote 74/99. Pregnancydiagnosis in ewes.

Farmnote 132/99. Teasingewes for early breeding.

Farmnote 46/97.Consequences of underfeeeding thepregnant ewe.

Bulletin No. 4148.Management for high lambingperformances from ewe flocks inthe Agricultural Area (1989).Department of Agriculture,Western Australia.

Genetics

Farmnote 58/96. LAMBPLANfor ram breeders.

Farmnote 63/95. LAMBPLANfor lamb producers.

LAMBPLAN Breeders Directory(see website;http://lambplan.une.edu.au)

LAMBPLAN Flock Genetic MeritListing (see website; http://lamb-plan.une.edu.au)

Merino Bloodlines: TheComparisons: 1989-1999. AgnoteDAI-52, Second Edition, July 2000.K.A. Coelli, K.D.Atkins, A.E.Casey andS.J. Semple Orange AgriculturalInstitute, NSW Agriculture, Orange

Merino Superior Sires, Centraltest sire evaluation results No. 6

(1999). Division of AnimalProduction , CSIRO, Armidale, NSW(also see website: http://mss.anprod.csiro.au)

Residues

Factsheets 1/2001. Commonlyused chemicals to treat sheep liceand blowflies.

Farmnote 12/2000. Woolresidues – market, environmentaland occupational health issues.

Farmnote. 13/2000. Sheep lice– cost effective management tominimise wool residues.

W E B S I T E S

9 8


T H E G O O D F O O D G U I D E F O R S H E E P

Websites of InterestAGWEST Trade and Market Development – Market informationhttp://www.agric.wa.gov.au/programs/trade/html/reports.htm

State Departments of Agriculture:

Department of Agriculture (Western Australia)http://www.agric.wa.gov.au

NSW Agriculturehttp://www.agric.nsw.gov.au/reader/2177

Queensland DPIhttp://www.dpi.qld.gov.au

Department of Agriculture, Fisheries and Forestry – Australiahttp://www.affa.gov.au

CSIROhttp://csiro.au

MLAhttp://www.mla.com.au

Kondinin Grouphttp://www.kondinin.com.au

Sheepmeat Council – Sheep industry newshttp://www.farmwide.com.au/nff/sheepmeat/mews.htm

The Woolmark Companyhttp://wool.com.au

Flockcarehttp://www.ausmeat.com.au

Lambplanhttp://www.ansc.une.au/lambplan

Merino Superior sireshttp://mss.anprod.csiro.au

Residueshttp://www.agric.wa.gov.au/wooldesk/chemresi.htmlhttp://www.cleangreenwool.com

G L O S S A RY

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ó Ad libitum fed without restriction.

ó Annual plants these plants have a life cycle each year.

ó Cellulose/lignin main chemical constituents of plant cell walls.

ó Condition score an estimation of the fatness of live sheep based on the flesh cover overthe back bone and short ribs. Condition score correlates with fat score on the carcase.

ó Crude protein (CP) the nitrogen containing constituent of feedstuffs. It is determined as thetotal nitrogen (N) content of the feed multiplied by 6.25.

ó Digestion the process by which food is digested.

ó Dry matter (DM) the weight of feed (pasture, fodder or grain) with all the moisture removed.

ó Dry Matter Digestibility (DMD) is the proportion of the dry matter (DM) consumed that is not excreted in the faeces. DMD is usually expressed as a percentage.

ó Enzymes any protein capable of causing a chemical reaction necessary to a cell.

ó Fat score an estimation of fatness over the twelfth rib on a carcase. Fat scorecorrelates with the condition score on live sheep.

ó Fat tail lambs lambs from fat tail sheep breeds, eg Awassi, Damara.

ó Feed intake the amount of feed eaten by sheep.

ó Feed on offer (FOO) the amount of feed available to sheep in paddocks. It is expressed as kilogram of dry matter per hectare.

ó Fodder crop crops (cereals, legumes and specific fodder crops) that are specifically planted for use as fodder by animals – conserved or standing.

ó Leaf area index (LAI) the ratio of total leaf area per unit of soil surface. It is the area thatinfluences the amount of photosynthesis. The larger the leaf area, the greater is the surface for the absorption of sunlight and so plant growth is enhanced.

ó Maintenance energy requirement is the energy needed so that the liveweight of a sheep can be maintained.

ó Metabolisable energy (ME) is the unit used to measure the energy content of feeds. It is the amountof energy available to the animal after taking into account the energy lostin the faeces, the energy lost in the urine, plus that lost as gases (methaneand carbon dioxide) produced when the rumen microbes ferment the feed. It is measured as millions (Mega) of Joules per kilogram of feed dry matter (MJ per kilogram of dry matter).

ó Non-protein nitrogen (NPN) the nitrogen available for use by sheep that does not come from the proteins eaten.

ó Nutritive value the nutritional worth of a feed.

ó Perennial plants plants that survive from year to year.

ó Phase pasture is the term used to describe a short period of legume pasture (one to three years) which is then followed by a ‘cropping phase’ of three to eightyears.

ó Organic compounds substances containing carbon.

ó Rumen the main part of the stomach of a ruminant where feed is fermentedand digested.

ó Rumen degradable protein (RDP) includes the dietary protein that is soluble in the rumen plus any non-protein nitrogen.

ó Rumen microbes the mixed population of bacteria and protozoa that are responsible for the digestion of feed in the rumen.

ó Undegradable dietary protein (RUP) is that portion of protein that is not digested in the rumen.

I N D E X

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crude protein 17, 82

curly windmill grass 41

digestibilityannual pastures 20, 21

feeds 5

digestible dry matter 15–16

diseases and disorders 90–4

see also specific conditions, eg. scabby mouthdrenching 83, 90–1

dry feedannual pastures 21–2

digestibility 21

limitations 22

dryland lucerne grazing systems 32–6

dwarf chickling 60

energy 15–16

supplementary feeding for 74, 75

energy requirement of the animal 16

enterotoxaemia 35, 59, 83, 90

environmental factors, and pasture options 25

erosion risks 28, 57, 60

see also water erosion; wind erosionexport market 10

see also live export market

faba bean stubble 59–60

faba beans 61, 62

fat-soluble vitamins 18

fat tailed breeds, live export 11

feed on offer (FOO) 22

seasonal availability 26

seasonal variability 23

use in grazing management 23

feed supplements see supplementary feedsfeedlots

area per lamb 80

feeding systems 80–1

siting 80

water availability and quality 80

feeds, energy content 15–16

field pea stubble 59

field peas 1, 62

firebreaks, hay made from 69

fodderas incomplete ration 66

cost of 6

nutritive value 66, 67

problems associated with 66–7

see also conserved fodder; green fodderforage pennisetums 48

frosted grain crops, hay use 69–70

glossary 100

glycogen, muscle 86, 87, 88

grain legume crops (matured)animal health issues 62

grazing trials 61

practical applications 62

abscess 92

acidosis 54, 56, 59, 62, 75, 81–2, 91

Albus lupin stubble 59

amino acids 14, 17, 76

ammonia 17

animal production, definition 14

animal welfare 84, 96

annual pasture legumes, for saltland pastures 29

annual pastures 20

digestibility 20

dry feed 21–2

for weaners 22

grazing management 22–3

green feed 20–1

in intensive cropping rotations 24, 25

insect control 24

need for supplementary feedingof lambs in summer 22

seasonal variability in growth 23

annual ryegrass toxicity 56, 67, 70, 94

arthritis 90

balansa clover 29, 30, 31, 45, 46

Barbers pole worm 46

barley, salt tolerance 33

bloat 35, 91

blue lupins see sandplain lupinsbluebush 29

calcium 17, 83

canola meal 17

canola stubbles 54

carbohydrates 14, 15

carryover lambs 9–10

caseous lymphadenitis 92

cellulose 14

cereal grains, calcium deficiency 17–18

cereal hay 69–71

cereal–legume hay 70–1

cereal stubbles 53, 54, 55

chaff-cart residues 54–5, 77–8

cheesy gland 12, 92–3

chickpea stubble 60

cobalt deficiency 18, 46

coccidiosis 83, 91

Computer Assisted Livestock Marketing (CALM) 8

conserved foddernutritive value 67, 69, 70

problems associated with 66–7

types of 68–72

see also specifics, eg. silagecontagious ecthyma 91

copper deficiency 18

cover cropping medic pasture with sweet lupins 63–4

cropping rotations, effects on pasture legume seedreserves 24

crossbred lambsgrowth on native perennial grasses 40–2

lot-feeding growth rate 83


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grain legume stubbles 56–60

and available watering points 56–7

constraints to liveweight gain 56

contribution to liveweight 56

wind erosion risk 57, 59

see also specific stubbles, eg. lupin stubblegrain supplements

nutritive value 76–7

problems with 75–6

grazing managementannual pastures 22–3

dryland lucerne 33

feed on offer (FOO) indicator 22, 23

lupin stubbles 57, 58

saltland pastures 30–1

sub-clover pastures 23

subtropical perennial grasses 44, 45, 46

summer fodder crops 49–50

tagasaste 37

to control insects 24

green fodderannual pastures 20–1

nutritive value 67

gross energy 15

growing season, and pasture production 20–1

halophytes 29

hay frozen pasture or crop 71–2

hays 9diseases caused by 67


types of 69–71

health requirements, sheep marketing 8

high grain diets, lot-fed lambs 81–2

high input system, carryover lambs 10

hydatid disease 93–4

information sources 96, 98

insect control, annual pastures 24

internal parasites 90–1

kikuyu grass 45, 46

lamb market 8

lambs, live export 11

Lathyrus stubble 60

leafy nine-awn 41

legume stubbles 53

see also grain legume stubbleslentil stubble 60

lice 83

lignin 14, 15

limestone 18

live export market 11–12

long seasons, and digestible dry matter 16

lot-feeding prime lambs 80–4

economics 83

feedlot consideration factors 80–1

finishing in small paddocks 81

growth rates 16, 83

health 83

husbandry/management 84

mob size 80

ration considerations 81–2

welfare and safe food issues 84

low input system, carryover lambs 9

lucerne (dryland)case study 35, 36

costs of establishment 32

economic value 35

feed quality 4

grazing management strategies 33, 35

landcare considerations 35

quantity and availability of feed 33–4

salt tolerance 33

sheep growth rates 35, 36

soil types and pH 32–3

special considerations 35

stocking rates 34

where to grow 32–3

lucerne hay 71

lupin hay 67, 71

lupin seed 58, 82

training weaners to recognise 58–9

lupin stubble 55, 56, 57

Albus lupin 59

expected weight gains 57

grazing strategy for prime lambs 57, 58

residual grazing 58

lupinosis 28, 56, 57, 67, 71, 83, 92

lupinsas cover crop for medic pasture 63–4

as supplementary feed 53, 54, 76

crude protein content 17

see also sandplain lupins; sweet lupins

macro-minerals 17

magnesium 87

maintenance energy requirement 16

maize 48

mature grass-dominant tropical pasture,digestible dry matter 15–16

meat colouracidity effects 86

feed additives to prevent stress 87

finish on high energy diets 86–7

muscle sugars influence on 86, 87, 88

shearing and feeding effects 87

significance of 86

medic pasture cover cropped with sweet lupins 63

trial results 63–4

medics, in pasture–crop systems 24

Merino lambs 10

lot-feeding growth rate 83

metabolisable energy content of feeds 15–16

metabolisable energy intake 16, 82

microbial protein 14, 16, 17, 74–5, 76

millets 48, 49

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mineral supplements 18

minerals 17–18, 82

molybdenum 18

Morawa dryland lucerne trial 36

muscle glycogen (sugars) 86, 87, 88

mutton market 12

native perennial grasses in permanent pastures 40–2

crossbred lamb production, case study 41, 42

feed quality 41, 42

neurotoxins 60

nitrate poisoning 35, 50

nitrogen 6

nitrogen excretion 17

nitrogen:sulphur ratio 76

non-protein nitrogen 6

nutritional requirements, ruminants 14–18

oaten grains, nutritive value 76–7

oaten hay 70

Orf 91

over the hook 8

oxalates 46

paddock sales 8

pasture availability, seasonal variation 26

pasture growthand rainfall 21

seasonal variability 23

pasture hay 71

pasture management tactics 24

pasture systems, for different environments 25

pennisetums 48, 49

perennial grasses 29

native 40–2

subtropical 43–6

perennial salt tolerant shrubs 29

permanent pastures 25

native perennial grasses in 40–2

persian clover 29, 30, 31

pest control, annual pastures 24

phase pastures 25

phomopsis 57, 59

phosphorus 17

pink eye 83, 93

plant protein 14

pneumonia 83, 93

pregnancy toxaemia 92

prime lamb market 8–10

Prograze manual 22, 24

protected protein 17

protein 6–17

protein supplementation 17, 74–5

protein synthesis 16, 17, 76

protein wastage 17

prussic acid poisoning 49, 50

puccinellia 29, 30, 31

pulpy kidney 35, 59, 83, 90

rainfalland feed on offer 23

and pasture growth 21

ram lambs, live export 11

red gut 35

redlegged earthmite 24

rotational grazinglucerne 33, 35

native perennial grass based pasture 41

saltland pastures 30

subtropical perennial grasses 44, 45, 46

rumen 4

rumen microbes 14, 16, 17, 53, 74–5

ruminantsnutritional requirements 14–18

uniqueness of 14

rumination 4

saleyard auction 8

saline soils, saltland pasture species for 29–30

salmonellosis 93

salt tolerancelucerne 33

subtropical perennial grasses 43

summer fodder crops 47

saltbush 29, 30

saltland pastures 9

costs of establishing 29

economic returns 31

feed quality 0–1


need for supply of good quality water 31

quantity and availability of feed 30

where to grow 29–30

sandplain lupins 27

Anthracnose in 28

as hay 71

available feed 27

grazing potential 27–8

problems to avoid 28

scabby mouth 91

vaccination against 8, 11, 83, 91

seasonal feed availability 26

seasonal variability, pasture growth 23

seed levels, measuring 58

selenium deficiency 18, 46, 83

serradellas 24, 45

Setaria pastures 6

sheep health issues 91–4

see also specific conditions, eg. lupinosissheep measles 94

sheep meat enterprises in WA 8–12

short seasons, and digestible dry matter 16

silage 68

diseases caused by 67

nutritive value 69

urea treated cereal silage 68–9

soil salinity 29–30

and lucerne growth 33


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soil types and pHlucerne 32–3

subtropical perennial grasses 43tagasaste 37

soluble sugars 14, 15

sorghums 47, 49

spear grass 41

split cereal grain 54

starch 14, 15

stocking ratesdryland lucerne 34

lupin stubbles 57–8

saltland pastures 30

sandplain lupins 28

subtropical perennial grasses 45–6

strawberry clover 45, 46

straws 2, 75, 77, 78

stress, and meat colour 86, 87

stubblescomposition 53

digestible dry matter 16


sheep performance on 52–5

see also specifics, eg. lupin stubblesub-clover pastures, grazing management 23

sub-clovers, in pasture–crop systems 24

subtropical perennial grassesclimate 43

cost of establishment 43–4

feed availability 44

feed quality 45

grazing management 44, 45, 46

health issues 46

salt tolerance 43

soil types and pH 43

stocking rates 45–6

sucker lambs 8–9, 21

sulphate of ammonia 16

sulphur 8

sulphur amino acids 76

summer fodder cropscase study, sorghum 49

feed quality 49

germination temperatures 50


grazing problems 50

landcare 50

production potential 48

salt tolerance 47


types of 47–8

supplementary feeding 74

during summer 22

for energy 74, 75

for protein and good rumen function 74–5

problems with grain supplements 75–6

successful 76–8

timing of 76

to maintain young sheep on stubbles 53

supplementary feeds 53, 54, 75–7

sweet lupins 61, 62

as cover crop for medic pasture 63–4

as hay 71

sweet sorghum 48, 49

tagasastecost of establishment 37

feed availability 37–8

feed quality 38

grazing management 37

growth rate of out of season prime lambs 38–9

rainfall zones 37

returns from 39


species 39

tall wheat grass 29, 30, 31

temperate millet 48

thiamine deficiency 18, 82

trace elements 17, 18

urea 16, 17, 49

urea treated cereal silage 68–9

urinary calculi 17, 83

urine 15, 17

vitamin A deficiency 18, 82, 83

vitamin B1 deficiency 18, 82

vitamin B12 deficiency 18, 83

vitamin D deficiency 82, 83

vitamin E deficiency 18, 82, 83

vitamins 18, 82

volatile fatty acids 14

WA blue lupins see sandplain lupinswater belly 17, 83

water erosion 80

water requirements 31, 56–7, 80, 94

water-soluble vitamins 18

water table, salt tolerant species to lower 30

waterlogged soils 29–30

weanerson sandplain lupins 28

supplementary feeding 22

training to recognise lupin seed 58–9

welfare (animal) 84, 96

Western Australian Meat Marketing Cooperative(WAMMCO) 10

wethers, live export 11–12

wheat stubble, digestible dry matter 16

wheaten hay 70

wind erosion 57, 59

windmill grass 41

windrowed pasture 71

wire grass 1

Woolpro manual 24

worms of sheep 90

yellow serradella, in pasture–crop systems 24

yolk boils 92

young ryegrass/clover pasture, digestible dry matter 15

IMPORTANT DISCLAIMERIn relying on or using this document or any advice or information expressly or impliedly contained within it, you accept allrisks and responsibility for loss, injury, damages, costs and other consequences of any kind whatsoever resulting directly orindirectly to you or any other person from your doing so. It is for you to obtain your own advice and conduct your owninvestigations and assessments of any proposals that you may be considering in light of your own circumstances. Further, theState of Western Australia, the Chief Executive Officer of the Department of Agriculture, the Agriculture Protection Board, theauthors, the publisher and their officers, employees and agents:ó do not warrant the accuracy, currency, reliability or correctness of this document or any advice or information expressly or

impliedly contained within it; and ó exclude all liability of any kind whatsoever to any person arising directly or indirectly from reliance on or the use of this

document or any advice or information expressly or impliedly contained within it by you or any other person.

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