Logo Module 2: Nutritional Strategies to Minimize Nutrient Loss to Manure By Dave Hansen

Logo

Module 2: Nutritional Strategies to Minimize Nutrient Loss to Manure

By Dave Hansen

Certified Nutrient Management Planning 2-2Logo

Goal

The goal of this module is to help producers maximize nutrient utilizationon their animal operations while avoiding waste and overfeeding.

Dave Hansen


Objectives

The main objectives of this module are to provide information to CAFO Owner/Operators regarding:

Basic concepts in animal nutrition.

How to improve nutrient yield.

Techniques for reducing ammonia loss.

Economic considerations when reducing nitrogen (N) and phosphorus (P) excretion.


Contents

1.Basic nutrient cycling in animal systems

2.National Research Council (NRC) guidelines

3.Dietary strategies to improve nutrient efficiency Dairy Beef Swine Poultry


Basic Nutrient Cycling

The idea is the same regardless of animal (or bird) type: to provide adequate nutrients while minimizing waste.

Providing nutrients in excess of animal requirements results in increased costs of production and contributes to potential environmental problems.


Basic Nutrient Cycling (continued)Inefficiencies can be caused by a variety of factors including housing conditions, management, genetics, and feed quality.

Nutrients available for growth

Feed provided

Feed waste

Intestinal secretions

(enzymes, cells)Nutrients absorbed

Feed consumed

Nutrients used for growth

Inefficiencies

Inefficiencies

Growth

Mismatch

Waste

Maintenance

Undigestedfeedand secretions

Nutrient paths in animal feeding operations.Source: van Heugten and van Kempen 2000


Nutrient Flow in an Animal Operation


Basic Nutrient Cycling

Nitrogen and P present different challenges.

Improving the efficiency of N use often includes changes in the source of N, such as improving forage quality or supplementing with amino acids.

Improving the efficiency of P use often includes reducing unnecessary additions of supplemental P (as with ruminants) or increasing the availability of dietary P through such techniques as adding phytase (as with swine and poultry).


NRC Guidelines

In 1916 the National Academy of Sciences organized the NRC to “…associate the broad community of science and technology with the Academy’s purposes of furthering knowledge and advising the federal government.”

The various subcommittees address animal nutrition issues and develop guidelines for each animal type.


NRC Guidelines (continued)

These guidelines are updated periodically to incorporate new information.

The following tables are for dairy, beef cattle, swine, and poultry.


NRC Guidelines: DairyHolstein, 1,5000 lb., average body condition 65 mo.age

90 Days in Milk Early Lactation Dry, Pregnant 270 Days in Gestation

BW 1,656 lb

Milk yield, lb/d 55 77 99 120 55 77

Dry matter intake lb/d

44.7 51.9 59.2 66 29.7 34.3 30.1

Net energy, Mcal/lb 0.62 0.67 0.7 0.73 0.94 1.01 .48

Diet % RDP 9.5 9.7 9.8 9.8 10.5 10.5 8.7

Diet % RUP 4.6 5.5 6.2 6.9 7 9 2.1

Crude Proteina % 14.1 15.2 16.0 16.7 17.5 19.5 10.8

Calcium, % 0.62 0.61 0.67 0.60 0.74 0.79 0.45

Phosphorus,% 0.32 0.35 0.36 0.38 0.38 0.42 0.23

Potassiumb, % 1.00 1.04 1.06 1.07 1.19 1.24 0.52

Sodium, % 0.22 0.23 0.22 0.22 0.34 0.34 0.10

Copperc, ppm 11 11 11 11 16 16 13

Zinc, ppm 43 48 52 55 65 73 22


NRC Guidelines: Beef, Finishing

Body Weight, lb. 525 650 775 900 1025 1150 Dry Matter Intake, lb/d 14 17 19.5 21.5 23.5 25.5

Crude Protein, lb/d

Daily Gain, lb. 1.0 1.22 1.36 1.49 1.57 1.65 1.72 1.8 1.55 1.69 1.82 1.86 1.91 1.95 2.5 1.87 2.01 2.13 2.14 2.15 2.16 3.3 2.18 2.32 2.43 2.40 2.38 2.36 4.0 2.49 2.62 2.73 2.66 2.60 2.54

Calcium, lb/d

1.0 0.04 0.04 0.05 0.05 0.00 0.05 1.8 0.06 0.06 0.06 0.06 0.06 0.06 2.5 0.08 0.08 0.08 0.07 0.07 0.07 3.3 0.10 0.09 0.09 0.09 0.08 0.08 4.0 0.11 0.11 0.10 0.10 0.09 0.09 Phosphorus, lb/d 1.0 0.02 0.02 0.03 0.03 0.03 0.03 1.8 0.03 0.03 0.03 0.03 0.04 0.04 2.5 0.04 0.04 0.04 0.04 0.04 0.04 3.3 0.04 0.04 0.04 0.05 0.05 0.05 4.0 0.05 0.05 0.05 0.05 0.05 0.05


NRC Guidelines: Beef, Cows

Months Since Body DM

CP

Calving Weight Intake Ca P

lb. lb. ------------------ lb/d ------------------ 0 (Calving) 1,340 24.6 2.20 0.06 0.04 1 1,200 26.8 2.71 0.08 0.05 2 (Peak Milk) 1,200 27.8 2.97 0.09 0.06 3 1,205 28.4 2.82 0.08 0.06 4 1,205 27.4 2.54 0.07 0.05 5 1,205 26.5 2.26 0.06 0.04 6 1,210 25.7 2.04 0.06 0.04 7 (Weaning) 1,215 24.2 1.45 0.04 0.03 8 1,225 24.1 1.49 0.04 0.03 9 1,240 24.0 1.57 0.04 0.03 10 1,260 23.9 1.69 0.06 0.04 11 1,290 24.1 1.89 0.06 0.04

Protein, Ca, and P requirements for beef cows


NRC Guidelines: SwineNutrient

Pig Weight 3-5 kg

(7-11 lb)

Pig Weight 5-10 kg

(11-22 lb)

Pig Weight 10-20 kg (22-44 lb

Pig Weight 20-50 kg

(44-110 lb)

Pig Weight 50-80 kg

(110-176 lb)

Pig Weight 80-120 kg

(176-265 lb) Crude Protein, %

26.0

23.7

20.9

18.0

15.5

13.2

Lysine, % total

1.5

1.35

1.15

0.95

0.75

0.60

Lysine, % appt. ileal dig

1.26

1.11

0.94

0.77

0.61

0.47

Calcium, % 0.90 0.80 0.70 0.60 0.50 0.45 P, % total

0.70

0.65

0.60

0.50

0.45

0.40

P, % avail.

0.55

0.40

0.32

0.23

0.19

0.15

Potassium, % 0.30 0.28 0.26 0.23 0.19 0.17 Sodium, % 0.25 0.20 0.15 0.10 0.10 0.10 Copper, mg 6 6 5 4 3.5 3 Zinc, mg 100 100 80 60 50 50


NRC Guidelines: Poultry-Chickens

Nutrient Layer-80a,b

Layer-100a,b

Layer-120a,b

Broiler 0-3 wk

Broiler 3-6 wk

Broiler 6-8 wk

Protein, % 18.8 15.0 12.5 23.0 20.0 18.0

Ca, % 4.06 3.25 2.71 1.00 0.90 0.80

Pc, % 0.31 0.25 0.21 0.45 0.35 0.30

Potassium, % 0.19 0.15 0.13 0.30 0.30 0.30

Copper, mg ? ? ? 8 8 8

Zinc, mg 44 35 29 40 40 40

Sodium, % 0.19 0.15 0.13 0.20 0.15 0.12

a Grams feed intake/hen dailyb Based on dietary metabolizable energy concentration of approximately 2,900 kcal/kg (1,318 kcal/lb) and an assumed 90% egg production rate (90 eggs daily per 100 hens).c Phosphorus is nPP.1Adapted from Tables 2-3, 2-6, 3-1, 5-1. Nutrient Requirements of Poultry, 9th Revised Edition, 1994. National Research Council.


NRC Guidelines: Poultry-TurkeysNutrient Turkey

0-3 wk 3-6 wk 6-9 wk 9-12 wk 12-15 wk 15-18 wk

Protein, % 28.0 26.0 22.0 19.0 16.5 14.0

Ca, % 1.2 1.0 0.85 0.75 0.65 0.55

P, %c 0.6 0.5 0.42 0.38 0.32 0.28

Potassium, % 0.7 0.6 0.5 0.5 0.4 0.4

Copper, mg 8 8 6 6 6 6

Zinc, mg 70 65 50 40 40 40

Sodium., % 0.17 0.15 0.12 0.12 0.12 0.12

a Grams feed intake/hen dailyb Based on dietary metabolizable energy concentration of approximately 2,900 kcal/kg (1,318 kcal/lb) and an assumed 90% egg production rate (90 eggs daily per 100 hens).c Phosphorus is nPP.1Adapted from Tables 2-3, 2-6, 3-1, 5-1. Nutrient Requirements of Poultry, 9th Revised Edition, 1994. National Research Council.


NRC Guidelines: Poultry-OtherNutrient Duck

0-2 wk

Duck

2-7 wk

Duck

Breeding

Turkey Tom

Turkey Hen

Protein, % 22.0 16.0 15 12.0 14.0

Ca,% 0.65 0.60 2.75 0.50 2.25

P,%C 0.40 0.30 ? 0.25 0.35

Potassium, %

? ? ? 0.4 0.6

Copper, mg ? ? ? 6 8

Zinc, mg 60 ? ? 40 65

Sodium, % 0.15 0.15 0.15 0.12 0.12a Grams feed intake/hen dailyb Based on dietary metabolizable energy concentration of approximately 2,900 kcal/kg (1,318 kcal/lb) and an assumed 90% egg production rate (90 eggs/100 hens daily).c Phosphorus is nPP.1Adapted from Tables 2-3, 2-6, 3-1, 5-1. Nutrient Requirements of Poultry, 9th Revised Edition, 1994. National Research Council.


Feed Waste Poor feeder design, poor feeder

management, and spoilage during storage can lead to losses as great as 20%.

Example: Swine “rooting” through feed can cause 3.4% waste.

Example: Feed costs account for as much as 70% of the cost of raising poultry–a little waste means big $$.


Dietary Strategies to Improve Nutrient Efficiency


Strategies for Dairy Producers Properly formulate

rations to Optimize milk yield. Minimize N, P, and

potassium excretion in urine/manure.


Strategies for Dairy Producers (continued) Precisely meet requirements for

Milk production. Maintenance. Gestation.


Key Concepts of Nutrient Balance on a Dairy Farm

Understand nutrient INPUTS, OUTPUTS, and % of nutrients that remain on the farm or that are lost to the environment.

Assess your nutrient balance. This allows you to determine management options that increase the recycling of nutrients from cropland to cattle and back to crops again.


Key Concepts of Nutrient Balance on a Dairy Farm (continued) The percentage of dietary N and P that remain

on the dairy farm can be as high as 76% and 81% (respectively).

Point: Profitable milk production includes both milk productivity and efficiency of nutrient utilization.


Nitrogen Strategies for Dairy Increase dry matter uptake. Improve forage quality. Consider forage protein fraction. Consider feeding method. Consider supplemental protein source. Monitor blood urea nitrogen (BUN) and milk urea

nitrogen (MUN).


Nitrogen Balance

76%71%64%% Remaining on farm

90.251.53.9Remainder

28.320.52.2Total Outputs

00.01Crops sold

1.91.90.1Cattle sold

26.418.62.0Milk

Output

118.572.06.1Total inputs

00.10Purchased cattle

13.914.61.3N fixation by legumes

78.543.83.8Purchased feed

26.113.51.0Purchased fertilizer

-----(tons of N per year)-----Input

50032045

Size of Dairy, Number of Cows*

Table Mass N balance for New York dairy farms.Source: Klausner 1993


A Few Terms and Definitions Crude protein (CP) = N x 6.25 Rumen degradable protein (RDP) = CP that is

degraded in the rumen; required by bacteria to grow

Rumen undegradable protein (RUP) = “escape or bypass” CP that is NOT degraded in rumen but passes to lower tract


Increase Dry Matter Uptake The percentage of CP required to supply adequate

protein for milk production varies with intake level.

Increasing dry matter intake by 5% reduces the CP needed by about 1%.

Higher intake levels also increase microbial protein synthesis in the rumen.

Increasing intake level, then, can decrease the need for higher dietary protein.


Improve Forage Quality “High-quality” forage contains more protein, less

fiber, and more energy, resulting in more protein and digestible dry matter for the animals, which can help reduce the amount of N inputs from off-farm sources.


Forage Protein Fractions

Supplementing a highly degradable (e.g., legume silage) forage with a less degradable forage (e.g., corn silage) can improve milk production at lower CP levels.

Common supplemental RUP sources include blood meal, distillers grains, and soybeans.


Feeding Method

Feeding sequence, frequency, and grouping strategy can impact N utilization.

Lactating cows require a proper balance of RUP and RDP to meet requirements for metabolizable protein (MP).

MP is the protein that the cow actually absorbs and uses for production.


Feeding Method (continued) Requirement for RUP = 35% to 38% of CP Requirement for RDP = 62% to 65% of CP A study by Van Horn (1992) showed the impact

of considering RUP and RDP. The lactating cows fed the proper amount of

RUP to supplement RDP generated 223 pounds of N per year in manure.


Feeding Method (continued)

The cows fed simply to satisfy Total CP (i.e., a higher percentage of RUP) generated 260 pounds of N per year in manure.


Monitor BUN and MUN The MUN test

> 18 mg/dl indicates that too much protein is being fed or there is not enough dietary starch.

High MUN is related to Lower reproductive performance. Higher feed costs. Health problems. Poorer milk production.


Monitor BUN and MUN (continued)

MUN analyses can be used to signal potential problems with feeding programs.


Phosphorus Strategies for Dairy Phosphorus is an expensive supplement. Most commercial mixes include P. Current guidelines specify 0.32% to 0.42% P for

lactating cows. It is common for producers to feed as much as

0.60% P. Numerous studies show no production benefit

from these high levels of P!


Phosphorus Balance

Mass P balance for New York dairy farmsSource: Klausner 1993

75%59%81%% Remaining on farm

18.26.21.8Remainder

6.04.30.43Total Outputs

000.01Crops sold

0.50.50.05Cattle sold

5.53.80.36Milk

Output

24.210.42.2Total inputs

00.030

14.28.41.0Purchased feed

5.52.01.2Purchased fertilizer

-----(tons of P per year)-----Input

50032045

Size of Dairy, Number of Cows*


Effect of P Intake on P Excretion

Increasing P content from 0.40% to 0.60% of diet dry matter increases P output from 40 to 69 lbs/cow/year!

0

10

20

30

40

50

60

70

0.4 0.5 0.6

P excretion (lb)


Sources of P High availability

Monocalcium phosphate Dicalcium phosphate Monosodium or ammonium phosphate

Medium availability Steamed bone meal Sodium tripolyphosphate


Sources of P (continued)

Low availability Low-fluorine rock phosphate Soft rock phosphate


Phytate P Phytate-P is not readily available to non-

ruminants such as swine. However, rumen microbes produce phytase.

Releases P from phytate So, phytate-P is available to ruminants. And, it is not necessary to over-supplement P

above requirements.


Feeding Excess P Costs $$$

P is the most expensive mineral commonly supplemented in dairy cows. Example: A diet containing 0.45% P vs. a diet

containing 0.55% P would save about $0.05 per cow daily.

For 100 cows a year, that is $1,825.


Feeding P: The Bottom Line

The milking herd should be grouped by production level so that multiple rations can be formulated over the complete lactation.


The Bottom Line for Dairies Are high milk yield and minimal nutrient excretion

mutually exclusive? No, you can do both! Focus on

Testing all forages/feeds. Properly formulating rations. Maximizing feed intake. Cow comfort and proper grouping.


Strategies for Beef Cattle Develop a general understanding of N (protein)

and P metabolism in feedlot cattle.

Understand current methods for decreasing N and P excretion by manipulating beef feedlot diets P requirements Protein requirements


Nitrogen Management

Discuss protein requirements Impact of lowering dietary N


Dietary Protein

All excess protein above requirements have no value.

Excess protein is absorbed in the small intestine. Protein is de-animated in the liver. Urea is subsequently excreted in urine at

the kidney.

Theory for lowering protein


Dietary Protein (continued)

Urea is rapidly converted to ammonia following deposition. Therefore, Feeding less protein leads to less urea

excretion. Lower urea excretion should decrease

ammonia.


Dietary Protein (continued)CP system Assumes all proteins are equal.

Important point: protein is N

% N * 6.25, protein is ~16% N

Does not account for bacterial needs.

Is simple but incorrect!


Protein RequirementsMP system DIP * TDN * microbe efficiency = BCP

(degradable N and energy)

Efficiency dependent on rumen pH, ~8-8.5

BCP*.64 to determine protein at S.I.

UIP * .80 to estimate protein at S.I.

BCP + UIP = MP


Protein Requirements (continued)

NH3 + carbon = microbial protein (BCP)

Feed proteinurea, corn protein

MP

DIPDIP

UIP

Rumen

Small Intestine

MP system

BCP BCP


N Balance Summary Overfeeding protein increases N losses.

Nutrition may: Decrease N inputs by 10% to 20%. Reduce N excretion by 12% to 21%. Reduce N volatilization by 15% to

33%.


N Balance Summary (continued) Volatilization depends on the time of year.

Summer–60 to 70% of N excreted Winter/spring–40% of N excreted

Based on annual occupancy, lose 50% of N excreted.


P Management

P intake

Ex.

AD

G

x

x

xx

x

x

x

xx

x xxx x

x

x

x

x

NRC predicts requirements from 0.22% to 0.32% of diet DM.


Dietary P in Feedlot Diets

0.270.35

0.520.59

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

85% Corn 85% Corn +Supplement

Byproduct Byproduct +Supplement

% d

iet

P (

DM

-bas

is)

SupplementByproductCornRoughage


P Requirements: Yearlings

0.14 16.4 28.3 3.64

0.19 19.9 27.5 3.64

0.24 27.6 28.9 3.72

0.29 32.0 27.5 3.55

0.34 36.2 28.5 3.84SE .7 1.0 .20

Bone Ash

P intake Phalanx

% DM g/d g % HCW

Erickson et al., 1999. J. Anim. Sci.


P Requirements: Yearlings (continued)

PhalanxMetacarpal

Erickson et al., 1999. J. Anim. Sci.


P Requirements: CalvesFeed % of Diet DM % P

High-moisture corn 33.5 0.32

Brewers grits 30.0 0.08

Corn bran 20.0 0.08

Cottonseed hulls 7.5 0.11

Animal fat 3.0 ----

Supplement 6.0 0.09Note: NaH2PO4 provided as top-dress supplement at increments of 0.06% P.

Base diet = 0.16% P, and 0.22, 0.28, 0.34, 0.40 Erickson et al., 1999. J. Anim. Sci.


P Mass Balance: Summer Yearlings Feedlot Pen

7.2 lbintake

1.9 lbanima

l5.3 lb

excreted

12.8 lbintake

1.9 lbanima

l10.9 lb

excreted0.35% P diet

0.24% P diet

REDUCED

44%

Erickson et al., ISAAFPW, 2000


P Mass Balance: Winter/Spring Calves Feedlot Pen

9.9 lbintake

2.4 lbanima

l7.5 lb

excreted

15.0 lbintake

2.5 lbanimal12.5 lb

excreted0.40% P diet

0.26% P diet

REDUCED

33%

Erickson et al., ISAAFPW, 2000


P Mass Balance (continued)

15,690 acres 8,624 acres

Assume: 50% of surrounding land used30 lb/ac P applied (agronomic)10,000 hd feedlot, 90 acres

0.35%-0.40% P234,000 lb/yr

0.22%-0.30% P128,000 lb/yr

Assume: (same)


P Balance Conclusions Overfeeding P leads to elevated manure P.

Nutrition may:

Decrease P inputs by 33% to 45%.

Reduce P excretion by 40% to 50%.

Direct reduction in acres needed

Expect manure removal = nutrient excretion for P


Beef Strategies Overview

Test feed. Use supplemental protein. Discontinue supplemental P. Consider phase feeding. Utilize differences between DIP and UIP. Use available tools to evaluate your rations.


Summary Nutrition can have a major impact on N and P

excretion for feedlot cattle. Phosphorus supplementation is unnecessary. It is difficult to further decrease P below what

corn provides. Utilizing an MP system may lower N excretion. Decreased urinary N excretion decreases N

volatilization losses.


Summary (continued) Volatization is a large concern. More management options and/or nutritional

techniques need to be explored. Fine-tuning requirements on the MP system is

needed. Eventually, metabolizable amino acids (AAs) will

be useful similar to the ideal protein concept in monogastrics.


Strategies for Swine Feed waste issues

Improving N management

AAs

Improving P management

Phytate-P


Nutrition: The Easy Way to Reduce Waste? Under field conditions, animals use nutrients with

mediocre efficiency:

P: 30%

N: 30% to 35% Under lab conditions:

N: 70%

P: close to 100% There is a lot of potential for reducing waste.


The Key: Understanding Inefficiencies in Nutrient Utilization Many steps are involved in

the utilization of nutrients. Each step has

inefficiencies associated with it.

The key to reducing waste is to understand where utilization can be influenced.

Nutrients available for growth

Feed provided

Feed waste

Intestinal secretions(enzymes, cells)

Nutrients absorbed

Feed consumed

Nutrients used for growth

Inefficiencies

Inefficiencies

Growth

Mismatch

Waste

Maintenance

Undigested feed and secretions


Feed Waste: An Expensive Loss of Nutrients Feed waste

Adherence: pigs take 1.5 g feed away from feeder 60 times/day (~ 4% of “intake”) Portion may be

returned. Spillage: pigs push

3.4% of feed out of feeder (in practice, range 1.5% to 20%).

Feed provided

Feed waste

Waste


Feed Waste: An Expensive Lossof Nutrients (continued) Presuming 5% waste on average:

Responsible for 7.5% of N in waste. Similar contribution for copper, zinc, and P 35% of carbohydrates

Major source of odor


Management: Key to Solving Feed Waste . . . Traditional guidelines:

Proper feeder care and adjustment can reduce feed waste drastically. Bottom of feeders should be 50% covered

with fresh feed.

• Pig needs to exert effort to eat.


Management: Key to Solving Feed Waste . . . (continued)

Feeders should be inspected at least weekly.

• Clean and adjust where necessary.


Feeder Design may add to the Problem. Feeders should be sized properly.

Only one pig per feeder space Challenge given that pigs change in size

Pigs should not have to step in feeders to gain access to feed.


Feeder Design may add to the Problem. (continued)

Feeders should be deep enough to prevent pigs from pushing out feed. Catch 22 but 8 inches deep seems to work

reasonably well.

• Problem exaggerated in wean-finish buildings.

Feeders should not have “dead” corners where feed gets trapped and spoils.


Feeder Design: The “Ideal” Pigs like to chew and swallow with their heads

straight. Traditional feeder design does not allow this over

the feeder. Pig needs to back up.

• Waste falls in the pit. Thus, feeders should be “spacious.” Filling level not an issue?


Present Feed in most Palatable Form. Feed should be pelleted.

Reduces feed waste ~5%

Dry feed is not very palatable. Pigs move back and forth from feeder to

waterer while eating, dropping feed.


Present Feed in most Palatable Form. (continued) Wet-dry or liquid feeders

Back and forth motion is prevented. Reduces feed waste Increases feed intake and weight gain


Select Highly Digestible Ingredients.

Feed Ingredient Digestibility, Content, Digestibility, Content,% % % %

Corn 85 8.5 14 0.28Soybean meal 48 87 49.0 23 0.69Soybean meal 44 84 45.6 31 0.65

Wheat 89 13.3 50 0.37Wheat bran 75 15.7 29 1.20Barley 85 10.6 30 0.36Sorghum 83 9.2 20 0.29Meat & bone meal 84 49.1 95 4.98Poultry byproducts 77 57.7 95 2.41

Fish meal 88 62.9 95 2.20Dicalcium phosph 100 18.50

PhosphorusProtein

Adapted from NRC 1998, and the Rhone-Poulenc Nutrition Guide 1993.


New Crops offer new Solutions.

Low-phytate corn and soybeans have much higher P digestibility.

Low-stacchyose soybean meal has higher protein and energy digestibility.

P %

Normal Corn Low-Phytate

Corn

Total 0.25 0.28

Phytate 0.20 0.10

Bio-available 0.05 0.21


Processing can Improve Nutrient Digestibility. Grinding:

Grind feed to uniform particle size of ~ 600 microns.

Pelleting: Improves protein digestibility 3.7%.


Processing can Improve Nutrient Digestibility. (continued) Expanding/extruding:

Improves pellet quality. Effects on digestibility are very diet-

dependent. Effects can be negative!


Opportunities with Enzymes

Fiber-degrading enzymes Wheat/barley/rye as major ingredients:

Xylanase/beta-glucanase improve digestibility 2% to 9%.

Corn-soy diets: Alpha-galactosidase, proteases, etc.

may prove effective.


Phytase Effect on P Availability Plants contain a large portion of P in the form of

phytate. Pigs cannot digest phytate.

Most plant P is thus unavailable.

Phytase can break down phytate, releasing the P. In a typical diet, P availability increases from

30% to 50%. 30% reduction in P excretion


Feed Quality Affects the Recycling of Enzyme Protein. High-fiber diets reduce the absorption of protein,

including enzymes. Fiber is the single most predictive factor for

apparent protein digestion. Has a strong negative influence


The More Ingredients that are used, the Better the Match!

Feed nutrients often are wasted because the diet is not ideal.

A 1% point reduction in dietary protein results in a 10% decrease in N excretion and ammonia emission.

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

Protein/10 arginine lysine SAA threonine

Per

cen

t

Requirement No synthetics

Lysine added Lys, Met, Thr, Try added


The More Ingredients that are used, the Better the Match! (continued)

Contributors to this issue: Small number of ingredients.

Limits flexibility in matching animal-specific profile.


Formulate on Available Nutrients.Availability of nutrients is not uniform.

In typical feed, N > P and Lys > Cys.

Presuming that all nutrients are equally available leads to larger mismatch, may hurt perfor-mance, and thus increases waste.

50

60

70

80

90

100

110

Soybeanmeal

Sunflowermeal

Rapeseedmeal

Gain

(re

lativ

e)

Total lysine Digestible lysine

Diets formulated on total or digestible amino acids


Diets Should be Optimally Matched to the Animal’s Requirement.

Nutritional requirements change with: Maintenance requirement (affected by sex,

age, and weight). Gain and composition of gain. Health status, environmental conditions, and

activity.


Examples of nutritional strategies:

Split-sex feeding Barrows require more energy for

maintenance than gilts. Increase energy-to-protein ratio of the

feed for barrows.

Diets Should be Optimally Matched to the Animal’s Requirement. (continued)


Diets Should be Optimally Matched to the Animal’s Requirement. (continued)

Temperature outside of thermo-neutral zone Energy is used for thermo-regulation.

Increase energy-to-protein ratio.


Phase Feeding Reduces Waste Nutritional requirements

change continuously. Protein-to-energy

ratio of feed de-creases with age. Diet should be

adjusted to match this decrease.

• Phase feeding

0.40

0.50

0.60

0.70

0.80

0.90

50 100 150 200 250bodyweight (lbs)

Lysi

ne

req

uir

emen

t (%

)

Continuous 3 phase 2 phase 1 phase


Phase Feeding Reduces Waste. (continued)

Inefficiencies occur when the diet provides more nutrients than the animal needs:

More phases = less waste


Phase-Feeding Diets are less Expensive. More phases = less waste and cheaper diets.

But also = more hassle Compromise between number of phases and

benefits achievable

In-line mixers/liquid feeding systems allow for continuously changing the diet composition without increasing hassle.


Diet cost obtained using least-cost feed formulation for a varying number of phases in the feeding program.

$39

$40

$41

$42

$43

1 2 3 4 5 6 7 8 9 10 11 12 13Number of phases

Die

t co

st p

er p

ig

Phase-Feeding Diets are less Expensive. (continued)


Precision Nutrition is Hindered by Feed Manufacturing Issues. Feed manufacturing issues

Variation in ingredient quality Somewhat compensated for by over

formulating (= more waste) Weighing errors Mixing problems


Precision Nutrition is Hindered by Feed Manufacturing Issues. (continued) All augment waste and possibly reduce

performance.

Weighing errors were observed in 14 feed mills specializing in swine feeds.

0

1

10

100

1000

10000

-100 -8

0-6

0-4

0-2

0 020 40 60 80 100

120

140

160

180

200

Weighing error (%±1)

Freq

uenc

y


Is Mineral Nutrition Overdone?

Diets are typically over-formulated as a measure of security. Increases waste.

Sow Diets Finisher Diets Mineral Req. Range Median1 Req. Range Median1 Calcium, % 0.75 0.62-2.01 1.21 0.50 0.57-1.38 0.96 Phosphorus, % 0.60 0.45-1.17 0.84 0.40 0.45-0.78 0.62 Copper, ppm 5 12-222 22 3 9–281 20 Zinc, ppm 50 79-497 167 50 103-205 149


Is Mineral Nutrition Overdone? (continued) The P requirement is higher for maximizing bone

strength than for maximizing gain. Difference of 0.1% point

For non-reproducing animals, formulating diets to maximize gain may be warranted.


Strategies for Poultry Nitrogen management

Amino acid

Phase feeding

Enzymes and additives

Phosphorus management

Available P

Phytate-P


Tracking N in Broilers

Feed N = 100%

Litter

Carcass

NH3-N

51.1%

18.3% 30.6%


Dietary Strategies for N Formulate on amino acids (AAs), not CP.

Optimize the dietary AA profile.

Phase feeding

Utilize the “true AA digestibility” of feeds.

Select feed ingredients with low nutrient availability.

Utilize enzymes and feed additives.

Avoid anti-nutritional factors.


Formulate on Amino Acids Formulating based on AA rather than CP can

lower N content by lowering dietary N input.

Utilizing AAs, such as methionine and lysine, reduces dietary protein from 18% to 16% and reduces the cost of the diet by more than $4/ton.

Although it is possible to reduce dietary CP levels by 3% to 4% (13%-22% N), there are biological limits to the amount of dietary protein that can be replaced with synthetic AAs.


NRC Requirement vs. 23% CP Corn/Soy Diet


Optimize the Dietary AA Profile Matching the birds' dietary AA with their

biological needs minimizes N excretion.

However, simply supplementing AAs, such as methionine and lysine, can result in excesses of other AAs that are then excreted.

A possible solution is an “ideal protein” supplement that provides all the essential AAs in their proper proportion.

These “proper proportions” are not always known!



Phase Feeding

The nutritional requirements of birds change over time. Example: Broilers require approximately 22%

CP at hatching and 16% CP at four weeks.

Commercial programs can include as many as six different phases to step down dietary protein.

Further refinements are possible based on feed sources and timing of grow-out period.


Utilize “True AA Digestibility.”

Amino acid digestibility varies with feed type.

Diets should be based on the digestible fraction rather than simply the amount of AAs present in the feed.

Calculated digestible AA requirements can be 8%-10% lower than total AA requirements.

Formulation based on digestible AAs improves daily gain and feed conversion.


Select “Low-Nutrient” Feeds. Variability in the nutrient values of common

feeds leads nutritionists to add a margin of safety, ensuring that nutritional needs are met. Example: The AA content of meat meal can

vary by as much as 45%.

Rapid ingredient analysis techniques, such as NIR, provide real-time information on the feed's nutritional value.

This information reduces the need for over-formulation as a safety margin.


Meat Meal Variation

AA A B C Mean CV %

Met 0.61 0.41 0.49 0.50 20.13

Cys 0.70 0.30 0.39 0.46 45.62

Lys 2.77 1.93 1.94 2.21 21.82

Thr 1.73 1.12 1.25 1.37 23.45

Arg 3.62 3.00 2.90 3.17 12.3


Utilize Enzymes and Additives. Water-soluble, nonstarch polysaccharides

(NSPs) impede digestion and absorption of fats, proteins, and carbohydrates.

Many important diet constituents, such as soybean and peas, contain complex NSPs.

Phytase improves the digestibility of AAs and protein as well as phytate-P.

Dietary enzymes can improve the digestibility of fiber and carbohydrates.


Avoid Anti-Nutritional Factors.

Many legumes and cereal grains contain compounds that have a negative effect on digestion and the availability of AAs and other nutrients. Soybean contain, among other things, a

trypsin inhibitor that impedes protein digestion.


Avoid Anti-Nutritional Factors. (continued)

Some beans, particularly field beans, have high concentrations of lectins that can reduce growth and decrease nutrient absorption.

Minimizing the use of these inputs will increase nutrient utilization by the birds.


Tracking P in Broilers

Feed P = 100%

LitterCarcass

57.4%35.0%


Dietary Strategies for P

Meet bird P requirements.

Select ingredients with available P.

Use vitamin D.

Use feed additives/enzymes.


Meet Bird P Requirements.

The NRC (1994) recommends 250 mg of available P (non-phytate) per hen per day

Leghorn breeders guide recommends 450 mg-460 mg/day early in lay and 288 mg-390 mg late in the cycle.

Research (Scott et al. 1999, Boling et al. 2000, and Angel 2000) suggests that the NRC guidelines are adequate.


Meet Bird P Requirements. (continued) In a four-week period, 1.2 million hens in a large

complex consume 7.4 million lbs of feed (3,696 tons).

If dietary available P were reduced from 450 mg to 250 mg/hen/day, it represents a $4.82/ton cost savings in dietary dicalcium phosphate, totaling $17,814 in feed costs.

With such a formulation, fecal P2O5 is reduced approximately 35,000 lbs in one month!


Select Ingredients with Available P. Birds do not absorb phytic acid, or phytate-P,

well.

Many cereal grains, such as corn and soybeans, have a high percentage of their total P in the phytate form, which results in an availability of less than 20%.

Animal meals and fish meal have nearly 100% available P.


Select Ingredients with Available P. (continued) Inorganic supplements also have a relatively

high P availability.

New products, such as low-phytate corn, are not yet commercially available but have two to three times as much available P as “standard” corn varieties.


Phosphate Supplement ComparisonCompound Biological Value

Beta-trical phosphate Std 100

Reagent: Monocal PO4 120-135

Reagent: Dical PO4 95-100

Feed: Phosphoric acid 115-125

Feed: Dical/Monocal P 105-115

Feed: Bone meal 90-100

Feed: Rock phosphate 55-75


Use Vitamin D.

Vitamin D deficiencies inhibit P metabolism.

Adding 1,25-dihydroxy vitamin D3 reduced phytate-P excretion by broilers by 35% and increased retention by 20% (Edwards 1993).


Use Feed Additives/Enzymes. Birds absorb phytate-P poorly because they lack

the enzyme phytase.

In addition to improving AA efficiency, adding phytase to poultry diets improves the digestibility of phytate-P.

Reductions in fecal P excretions from using phytase can be as much as 40%.



Use Feed Additives/Enzymes. (continued) Enzymatic “cocktails” containing a mixture of

enzymes, including phytase, have been found to be more effective that phytase alone.

Such cocktails can improve calcium retention, weight gain, feed conversion, and toe tibia ash.


Numerous dietary and management strategies exist to reduce

N excretions. P excretions.

Significant reductions can be achieved without significant expense by using the information and guidelines available from the NRC and from various research and Extension publications.

Overall Summary

Documents

Logo Module 2: Nutritional Strategies to Minimize Nutrient Loss to Manure By Dave Hansen