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Ewe Nutrition for Lambing
Grassroots Ewe Nutrition 01
In this bookletEwe Nutrition for Lambing
Introduction 02
Why is nutrition so important? 03
Understanding the problem 04
Nutritional planning 05
Tools for assessing nutritional needs 06
Common nutritional problems 07associated with ewes pre-lambing
Other indicators of poor nutrition 08
What to do next 09
Grassroots Ewe Nutrition02
The booklet has been writtenwith the help of the followingXLVet members:
Russell Fuller VetMB MRCVS,Tyndale Vets
Joe Henry BVMS MRCVS,Alnorthumbria VeterinaryGroup
Iain Richards BVSc Cert SHP,XLVets
The majority of conditionsseen in sheep
around lambingtime are directlyattributable to
inadequate nutrition.
IntroductionEwe Nutrition for LambingCorrect ewe nutrition is perhaps the single most influential factorbehind periparturient losses, fromadult sheep as well as lambs.
Much has been done in recent years to providecorrect nutritional advice for dairy farmers, withpart of the approach being ration formulation. This booklet discusses many of the problems thatare associated with ewe nutrition and providespractical solutions to them. It contains some recentresearch material as well as simple and practicaladvice from sheep practitioners.
Why is nutritionso important?
The twin-bearing (or more) ewe is under great nutritional stressduring the last six weeks of pregnancy. This relates almostentirely to the huge demand that the multiple foetuses placeupon the ewe at a time when she is increasing the growth of her udder and coping with a combination of low food availability and poor weather.
The majority of conditions seen in sheep aroundlambing time are directly attributable to inadequatenutrition. This can include problems such as smothering, which may be due to an underfed lambbeing too weak to get out of the way. Getting thefeeding right will increase lamb survival, increaseprofits and reduce labour.
If you have had problems in your flock relating to any of the following, nutrition is likely to be the primary cause:
l Twin lamb disease
l Hypocalcaemia
l Hypothermia of lambs
l Joint ill (naval ill)
l Watery mouth/rattle belly
l Liver abscesses
l Pneumonia
l Lamb dysentery
Even conditions that occur later in the lamb's life,such as joint ill or some of the clostridial diseasescan be attributable to poor colostrum, as a result of poor nutrition.
Ewe nutrition can be simplified into energy and
protein requirements
Grassroots Ewe Nutrition 03
Grassroots Ewe Nutrition04
Understandingthe problem
Practical issues:l Grazing
l Housing
l Trough space
l Water availability
l Ewe health
l Lamb numbers
The fitness of a ewe to carry lambs to term shouldbe assessed as part of a pre-tupping routine.However, conditions such as lameness, which willreduce the ewe's ability to walk to available food,can arise later into pregnancy and need to be considered and adjustments made to help the ewe. Many farmers are naturally concerned aboutturning over pregnant ewes; however, the recentadvances in lameness suggest it may be moreappropriate to treat lame sheep with an antibioticprescribed by your vet. This will be of minimal interference and has no ill-effect on the growing lambs.
Physical constraints:A ewe can only consume 2-2.5% of her bodyweight in dry matter (DM), therefore all the requirements for this period of intense growth mustbe contained in this volume. For an 80kg ewe thisequates to 1.6 to 2.0kg DM. This is complicated by a 10% reduction in dry matter intake (DMI) duringthe final two weeks of pregnancy.
In the last six weeks ofpregnancy the followingtakes place:
l The lamb has its greatest growth
l The ewe's udder grows
l Colostrum is produced
l Brown fat is laid downin the lamb
This all places greatdemands upon the ewefor energy and protein.She therefore needs a balanced diet as well asbeing able to physicallyeat and drink.
Nutritional planning
Ewe nutrition can be simplified into energy and protein requirements and in many cases energycan be the main focus. As the lamb can only utiliseglucose, the diet must provide sufficient for thelamb and for the ewe's daily needs. The energyrequirements for ewes carrying different numbersof lambs is well established and can be comparedto the energy available for the diet. The bulk ofenergy has to come from forage so that a forageanalysis is vital. In creating a diet, it is accepted thatthere can be huge variation between forages, even form the same field, but the analysis forms a starting point. Fine tuning is discussed later.
By knowing the forage analysis, the analysis of theconcentrate and the calculated DMI of the ewe, theenergy content of the ration can be determined. By comparing this to the known requirements, theenergy excess or deficiency can be seen and anycorrections made. Whilst the calculations are notdifficult, your XLVets practice has a nutritionalspreadsheet that can perform these.
This method can also be applied to homemadediets, and to a TMR.
Assuming all other factorslisted before are correct,the make-up of the dietbecomes the most important factor. Themajority of farms will usea combination of grazing,forage (hay or silage) andcommercial concentrates.This will be augmented or replaced by straightssuch as fodder beet. Ifcommercial concentratesare used, then macro andmicro mineral balanceswill probably be correct.If, however, a home-maderation is used, mineralrequirements need to be considered.
Grassroots Ewe Nutrition 05
Grassroots Ewe Nutrition06
Tools for assessing nutritional needs
Scanning for foetal numbers is a very cost effective procedure that can make a huge difference to ewe feeding for the following reasons:
l Barren ewes are identified early, so donot receive supplementary feeding
l Single bearing ewes can be identifiedand fed accordingly, they may get
sufficient energy from forage alone,reducing supplementary feed costs
l Twin and above ewes are identified so thatthey can be fed and monitored separately
As well as being beneficial for nutrition, identifying foetal numbers can help as part ofyour worming plan, if wormers are to be used at lambing.
This is another vital aspect of ewe feeding.The ideal Body Condition Score (BCS) atlambing is 3.0-3.5 for lowland breeds and 2.5-3.0 for hill breeds. If ewes are in poorercondition then supplementary feeding needsto start earlier. If in good condition, then someenergy deficits can be overcome by relying on the ewe's own reserves.
Scanning
Condition scoring
It is well known that all the planning possiblecannot accurately predict how a diet is actually fed. The only way to accuratelyassess the diet is to test the ewes to find outhow they are responding through blood samples. This is best done approximately sixweeks before lambing, ideally with a minimumof six ewes from each management group.
Analysis can include the following:l B-hydroxybutyrate (BHB)
l Albumin
l Total protein
l Blood Urea Nitrogen (BUN)
l Calcium
Results from the analysis above willshow if the energy or protein contentof the diet needs adjusting.
Fine tuning and metabolic profiles
Survival rates of ewes with twin lamb diseaseis generally considered poor and there are amultitude of treatment regimes, all havingvarying success. There is an argument thatthe effort and cost of treatment is better putinto the remaining healthy ewes.
TREATMENT OPTIONS:Glucose supplementsTwin lamb disease is a hypoglycaemia in the ewe, so replacing this is desirable. However thedemands are such that even a constant intravenous infusion may not be sufficient, althoughis a good measure in the short term. Oral glucosewill not work as it is metabolised by rumen flora so glucose precursors such as glycol need to beused. Work from one XLVet practice suggests that dosing four times a day is more beneficial than the traditional twice daily regime.
SteroidsMuch has been made recently of the use of lowdose dexamethasone. However, as the twin lambewe is known to have high level of circulating corticosteroid it is difficult to see how this would beeffective so further discussion with your XLVetspractice would be recommended for this option.
Non-steroidal drugs (NSAID's)Recent work has also shown the use of NSAID's to be effective. There is evidence to show that thecomplex biochemistry associated with twin lambcauses release of inflammatory factor that have an effect on appetite. Suppressing these canencourage the ewe to eat.
Inducing birthAs the major reason for the occurrence of twinlamb disease is the presence of the lambs, inducing birth is often the best means of a cure.However, this can be difficult to achieve in practiceand should be discussed in detail with your veterinary surgeon.
Twin lamb diseaseTwin lamb disease shouldbe considered not as anindividual condition, butas a warning that theflock is under nutritionalstress. This would applyeven if another illness or condition, such aslameness, is present in the ewe.
Common nutritional problems associated with ewes
pre-lambing
Grassroots Ewe Nutrition 07
Grassroots Ewe Nutrition08
Other indicatorsof poor nutrition
Ewe mastitis/AgalactiaInsufficient milk, in an otherwise healthy ewe, isalmost certainly due to poor ewe nutrition, so anycases of mastitis or agalactia should be consideredas a warning of inadequate flock nutrition.
Increased numbers ofhypothermic lambsWhilst cold and wet weather can be a problem,large numbers of hypothermic lambs would suggest poor ewe feeding. Unless conditions arevery severe, a lamb should have enough reservesof brown fat to be able to stand and suckle.
Lamb deathUsing post mortems to assess nutritionAn uncomplicated post-mortem examination on a lamb takes very little time and can provide vital information. The lamb will first be examined externally to see if it has walked (i.e. stood to suckle).
Then, internally your vet will assess the following:
l Lungs - inflated/not inflated
l Stomach - full/empty
l Intestines - full/empty
l Brown fat - present/absent/used
l Abscesses
l Trauma - rib fractures and liver ruptures
Undertaking a basic post mortem on a number oflambs can highlight commonalities, for example ahigh number of lambs that have not suckled, soadjustments to management or diet can beimplanted on-farm.
Even conditions that occur later in the lamb's life, such as joint ill or some of theclostridial diseases can be attributable to poor colostrum,as a result of poor nutrition.
What to do next
Contact your local XLVetspractice and ask to speak tosomeone about GrassrootsEwe Nutrition for Lambing.
To find your local XLVetspractice and learn moreabout feeding ewes toensure success at lambingtime visit the XLVets website www.xlvets.co.uk.
Grassroots Ewe Nutrition 09
LAMBING CHECKLISTq Arm length disposable gloves
q Lubricant
q A head rope or lambing snare
q Disinfectant solution
q Calcium injection
q Energy supplement like propylene glycol to treat twin lamb disease
q Syringes and needles
q Antibiotic injections for treating mastitis and metritis
q Anti-inflammatory injection for use after lambing
q Prolapse retainers
q Strong iodine (10% tincture of iodine)for dipping navels
q Colostrum (ideally frozen sheepcolostrum, if not goat or cow or powdered colostrum substitute)
q Thermometer
q Stomach tubes
q A warming box
q Glucose for intraperitoneal injection of hypothermic lambs
q Oral antibiotics for watery mouth treatment
www.grassroots.xlvets.co.uk
