NDSU Animal and Range Sciences Nutritional Strategies to Reduce Nutrient Excretion and Odor in Beef, Dairy, and Swine Operations Dr. Greg Lardy

NDSU Animal and Range Sciences or Precision Nutrition for Livestock Feeding Operations

NDSU Animal and Range Sciences Outline Introduction What nutrients should we be concerned with? Phosphorus Nitrogen Dietary strategies to minimize excretion

NDSU Animal and Range Sciences Nutritional Strategies in Beef Cattle Operations

NDSU Animal and Range Sciences Rumen Diet P g/d Saliva P ~30-40 g/d Serum (~1 g) Intestine Fecal P Source: Wadsworth and Cohen, lb steer example Meat & Organs ~450 g P Bone ~2000 g P P Metabolism in Beef Cattle

NDSU Animal and Range Sciences Dietary P in Feedlot Diets

NDSU Animal and Range Sciences P intake, g/d ADG, lb/d NRC recommendation Industry Average P Requirements in Yearlings Source: Erickson et al., 1999

NDSU Animal and Range Sciences P intake, g/d ADG or F:G (lbs) ADG F:G P Requirements in Calves NRC recommendation Industry Average Source: Erickson et al., 1999

NDSU Animal and Range Sciences urinary P fecal P P intake, g/d Total P excreted, g/d P Excretion in Calves Source: Erickson et al., 2001

NDSU Animal and Range Sciences Cannot determine P requirements, too low – Bones, blood, performance Does the requirement matter? NRC recommendations for feedlot cattle are too high Industry has markedly overfed (relative to requirement) – Progress has been made Implications: $ & environment P Requirements

NDSU Animal and Range Sciences 15,690 acres 8,624 acres Assume: 50% of surrounding land used 30 lb/ac P applied (agronomic) 10,000 hd feedlot, 90 acres.35 to.40% P 234,000 lb/yr.22 to.30% P 128,000 lb/yr P Mass Balance F or a 10,000 Head Feedlot Assume: (same)

NDSU Animal and Range Sciences Assumes all proteins are equal Important point: protein is nitrogen %N * 6.25, protein is ~16% N Does not account for bacterial needs in ruminants Is simple, but incorrect Protein Requirements Crude Protein (CP) System

NDSU Animal and Range Sciences NH 3 + Carbon = Microbial Protein (BCP) Feed protein urea, corn protein MP DIP UIP RUMEN SMALL INTESTINE Metabolizable Protein (MP) System BCP Protein Requirements

NDSU Animal and Range Sciences Predicted requirement over feeding period Protein Requirements

NDSU Animal and Range Sciences Requirement compared to industry average diets Protein Requirements

NDSU Animal and Range Sciences Change the diet to match these requirements, i.e. PHASE FEED Protein Requirements

NDSU Animal and Range Sciences Initial wt., lb Final wt., lb DM Intake, lb·d a 24.5 b ADG, lb·d Feed efficiency.158 a.166 b.170 a.164 b ITEM ConPhaseConPhase YearlingsCalves Performance Impacts Source: Erickson and Klopfenstein, 2001

NDSU Animal and Range Sciences 72.8 lb intake 7.9 lb animal 64.9 lb excreted 16.7 lb (26%) manure 2.1 lb (3%) runoff Average diet N, 13.5% CP 46.0 lb (71%) volatilized N Mass Balance-Conventional Feeding Yearlings (Summer) Source: Erickson and Klopfenstein, 2001 Feedlot pen

NDSU Animal and Range Sciences N Mass Balance Phase-Fed Yearlings (Summer) Feedlot pen 59.4 lb intake 7.9 lb animal 51.5 lb excreted 18.7 lb (36%) manure 1.5 lb (3%) runoff 31.3 lb (61%) volatilized Source: Erickson and Klopfenstein, 2001

NDSU Animal and Range Sciences N Mass Balance Phase-Fed Yearlings (Summer) 59.4 lb intake 7.9 lb animal 51.5 lb excreted 18.7 lb (36%) manure 1.5 lb (3%) runoff 31.3 lb (61%) volatilized REDUCED 19 % REDUCED 32.5 % Source: Erickson and Klopfenstein, 2001 Feedlot pen

NDSU Animal and Range Sciences 81.4 lb intake 10.1 lb animal 71.3 lb excreted 39.9 lb (56%) manure 2.1 lb (3%) runoff 29.3 lb (41%) volatilized Average diet N, 13.5% CP N Mass Balance Calves Fed Conventional Diet in Winter-Spring Source: Erickson and Klopfenstein, 2001 Feedlot pen

NDSU Animal and Range Sciences 72.2 lb intake 10.0 lb animal 62.2 lb excreted 35.0 lb (56.5%) manure 2.2 lb (3%) runoff 24.9 lb (40%) volatilized N Mass Balance Phase-Fed Calves in the Winter-Spring REDUCED 15 % REDUCED 12.5 % REDUCED 11.3 % Source: Erickson and Klopfenstein, 2001 Feedlot pen PHASE fed

NDSU Animal and Range Sciences Overfeeding protein increases N losses Nutrition: – may decrease N inputs by 10 to 20% – reduces N excretion by 12 to 21% – reduces N volatilization by 15 to 33% N Balance Summary

NDSU Animal and Range Sciences Volatilization is dependent on 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 N balance Summary (continued)

NDSU Animal and Range Sciences Nutritional Strategies in Dairy Operations

NDSU Animal and Range Sciences The Challenge for Dairy Producers Properly formulate rations to Optimize milk yield Minimize N, P, and K excretion in urine/manure

NDSU Animal and Range Sciences 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! Lactating cows require ~0.40% P excretion (lb) [P] in Diet Lbs of P Excreted

NDSU Animal and Range Sciences Protein Degradability and N Excretion RDP: rumen degradable protein Diets with high RDP result in greater excretion of N in manure Diets need adequate RUP (rumen undegradable protein), or “escape” protein N excretion (lb) High RDP Low RDP

NDSU Animal and Range Sciences The Bottom Line  The amount of N, P, and K in the diet has a HUGE effect on the yearly excretion of these nutrients

NDSU Animal and Range Sciences Milk Production and Land Needed As milk yield increases, so do nutrient requirements and nutrient excretion For herds producing 70 to 100 lbs of milk, a 100-cow group will require acres to manage N ~1.5 acres per cow Need at least 2.25 acres per cow for P

Dietary N and P: Effect on Land Needed 19.5% CP diet (alfalfa, no supplemental RUP) vs. 17.0% CP (using RUP) results in 20% more N in manure and 20% more land needed For 100-cow group, you would need up to 25 acres more land Dietary P ranging from 0.43% to 0.52% results in 30% more land needed 100-cow group needs 50 more acres of land

Phosphorus Requirements High-producing dairy cows require ~0.40% P in the diet DM for OPTIMAL Milk production Reproductive performance Dry cows require ~0.25% P in dietary dry matter However, it is not uncommon to feed 0.50% to 0.60%

NDSU Animal and Range Sciences Feeding Excess P Costs $$$ P is the most expensive mineral commonly supplemented in dairies Example: Feeding 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

Use Sources of Phosphorus With High Availability High availability Monocalcium phosphate Dicalcium phosphate Monosodium or ammonium phosphate Medium availability Steamed bone meal Sodium tripolyphosphate Low availability Low-fluorine rock phosphate Soft rock phosphate

NDSU Animal and Range Sciences Phytate Phosphorus Phytate-P is not readily available to nonruminants such as swine Generally found in plant forms of P Rumen microbes produce phytase Releases P from phytate Phytate-P is available to ruminants

NDSU Animal and Range Sciences Potassium Requirements The requirement is about 0.90% to 1.2% of diet DM During heat stress, increase K to 1.5% or 1.6% When heat stressed, more K is lost via sweat and saliva The maximum tolerable level is 3.0% diet DM

NDSU Animal and Range Sciences Potassium Supplementation Supplementation seldom needed If needed, use potassium chloride or other commercial premix Most forages contain high K concentrations Do not rely on book values Often, analyzed values are much higher than listed in books

NDSU Animal and Range Sciences RUP and RDP Requirements Lactating cows require 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 Requirement for RUP = 35% to 38% of CP Requirement for RDP = 62% to 65% of CP

NDSU Animal and Range Sciences Feeding Strategies to Control N Excretion Increase dry matter intake Improve forage quality Consider forage protein fractions Consider feeding method Consider supplemental protein sources

The Bottom Line Are high milk yield and minimal nutrient excretion mutually exclusive? No, you can do both! Focus on Testing all forages/feeds Properly formulating rations Soil testing Proper soil fertilization Maximizing feed intake Cow comfort and proper grouping

NDSU Animal and Range Sciences Nutritional Strategies in Swine Operations

NDSU Animal and Range Sciences Under field conditions, animals use nutrients with mediocre efficiency: –Phosphorus: 30% –Nitrogen: 30% to 35% Under lab conditions: –Phosphorus: almost 100% –Nitrogen: 70% There is a lot of potential for reducing waste Nutrition: The Simple Way to Reduce Nutrient Excretion

NDSU Animal and Range Sciences Feed Waste: An Expensive Waste of Nutrients Feed waste: Adherence: pigs take 1.5 g feed away from feeder 60 times per day (~ 4% of “intake”) Spillage: pigs push 3.4% of feed out of feeder (practical range 1.5% to 20%) Feed provided Feed waste Waste

NDSU Animal and Range Sciences Presuming 5% waste on average Responsible for 7.5% of N in waste Similar contribution for Cu, Zn, P 35% of carbohydrates Major source of odor Feed Waste: An Expensive Waste of Nutrients

NDSU Animal and Range Sciences Management is Key Traditional guidelines Proper feeder care and adjustment can reduce feed waste drastically Bottom of feeder should be 50% covered with FRESH feed –Pig needs to exert effort to eat Feeders should be inspected at least weekly –Clean and adjust where necessary

NDSU Animal and Range Sciences 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 feeder to gain access to feed

NDSU Animal and Range Sciences Feeder 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 Feed gets trapped and spoils Feeder Design May Add to the Problem

NDSU Animal and Range Sciences 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 Augments feed waste

NDSU Animal and Range Sciences Wet-dry or liquid feeders Back and forth motion is prevented Reduces feed waste Increases feed intake Increases gain Present Feed in Most Palatable Form

NDSU Animal and Range Sciences Not All Nutrients in the Diet Are Digested For a typical diet, 8% of protein and 70% of phosphorus is not digested Indigestible proteins are fermented in large intestines Contribute to odor Remains are excreted Contribute to waste Feed provided Feed waste Waste Intestinal secretions (enzymes, cells) Inefficiencies

NDSU Animal and Range Sciences Select Highly Digestible Ingredients

NDSU Animal and Range Sciences New Crops May Offer Solutions As Well Low-phytate corn and soybean have much higher phosphorus digestibility Low-stacchyose soybean meal has greater protein and energy digestibility

NDSU Animal and Range Sciences Opportunities to Improve Digestibility Processing feed properly Grinding Pelleting Addition of exogenous enzymes to improve digestibility Phytase Xylanase or beta-glucanase Wheat or barley based diets

NDSU Animal and Range Sciences Processing Can Improve Nutrient Digestibility Grinding Grind feed to uniform particle size of ~ 600 microns Pelleting Improves protein digestibility 3.7%

NDSU Animal and Range Sciences Other Opportunities to Improve Digestibility Addition of enzymes Wheat and barley based diets Xylanase/beta-glucanase Improve digestibility by 2 to 9% Use of phytase to improve P availability 30 to 50% improvement

NDSU Animal and Range Sciences Maintenance Results in Waste Feed provided Feed waste Intestinal secretions (enzymes, cells) Nutrients absorbed Feed consumed Inefficiencies Waste Undigested feed and secretions Maintenance Maintenance is obligatory Basic function of life Nutrients used for “maintenance” are ultimately catabolized (broken down) Maintenance requirement depends on size of animal

NDSU Animal and Range Sciences Reduce Relative Maintenance Costs by Increasing Gain By improving daily lean gain, maintenance waste becomes relatively less important Optimize production Optimize management Optimize animal health Optimize nutrition, etc.

Base Formulations on Available Nutrients Availability of nutrients is not uniform N > P, and Lys > Cys in typical feed Presuming all nutrients are equally available increases waste Diets formulated on total or digestible amino acids 10-58

NDSU Animal and Range Sciences Match Diet to 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

NDSU Animal and Range Sciences Examples Split-sex feeding  Barrows require more energy for maintenance than gilts  Increase energy to protein ratio of the feed for barrows Match Diet to Animal’s Requirement

Where Does All of the Waste End Up? Feces contain the remnants of the digestive process Undigested feed Endogenous losses Odor Excess zinc and copper Excreted through bile and excreted as feces Uptake of calcium and phosphorus is regulated Excess is excreted in feces Feed waste Inefficiencies * enzyme prod. * tissue accretion Mismatch Undigested feed and secretions Maintenance } Feces Urine Manure pit

NDSU Animal and Range Sciences Urine contains the remnants of metabolism Urea from protein breakdown Some diverted to feces Excess potassium, sodium, and chlorine Where Does All of the Waste End Up?

NDSU Animal and Range Sciences Summary Nitrogen and phosphorus are key nutrients to focus on Nutrient excretion can be reduced by proper nutrition Feed to animal’s requirements Test feedstuffs Reduce feed waste

NDSU Animal and Range Sciences Questions??

NDSU Animal and Range Sciences Acknowledgements This presentation was adapted from the LPES curriculum which is available at: