Are We Feeding Our Cows Too Much Protein

Are We Feeding Our Cows Too Much Protein? Degradation Feed Proteins (Esophagus) Peptides & Free AA World Dairy Expo October 2005 URINE Feed NPN Microbial Synthesis Escape (Omasal orifice) MICROBE PROTEIN Ammonia overflow NH 3 N-Recycling LIVER UREA Glen Broderick U.S. Dairy Forage Research Center Madison, Wisconsin USDFRC Dairy Cows Uses Crude Protein 2-3 X More Efficiently than Beef Animals USDFRC Feed N utilization Manure N utilization USDFRC How can Nitrogen Excretion be Reduced Without Losing Production? USDFRC Strategies to Reduce N Excretion 1. 2. 3. Feed the Minimum Crude Protein (CP). Accurately Track Dietary CP. Use Model (e.g., NRC) to Meet Needs for RumenDegraded Protein (RDP) & Rumen-Undegraded Protein (RUP). Reduce Rumen Degradability of Forage CP. Feed “Complementary” RUP & Protected AA. Use New Approaches to “Fine-Tune” Feeding. 4. 5. 6. USDFRC Effect of CP (Solvent SBM) or Energy on Protein Yield 2.50 -----32% NDF----b b -----28% NDF----a a a Milk protein, lbs/day 2.25 -----36% NDF----cd cd c 2.00 d 1.75 1.50 15.1 16.7 18.4 15.1 16.7 18.4 15.1 16.7 18.4 USDFRC Dietary CP, % Effect of CP (Solvent SBM) on Milk & Protein Yield (Olmos & Broderick, 2003) 85 Milk yield max = 16.7% CP Milk yield, lbs/day 80 2.75 Milk protein, lbs/day 75 Milk protein max = 17.1% CP 2.50 70 13 14 15 16 17 18 19 2.25 20 USDFRC Dietary CP, % of DM Effect of Forage Source & CP on Production (Wattiaux & Karg, 2004) Forage/CP (%) Alfalfa silage Corn silage 16.5 18.0 16.2 17.1 53.8 101.6 101.6 3.77 2.80 11.7 55.8 103.0 102.3 3.51 2.80 12.2 53.4 108.7 101.4 3.35 2.91 11.5 54.0 107.4 101.2 3.26 2.89 12.8 Prob.1 For. Prot. 0.41 0.03 0.84 0.08 0.20 0.35 0.30 0.97 0.95 0.35 0.88 < 0.01 Item DMI, lb/d Milk, lb/d 3.5% FCM, lb/d Fat, lb/d True protein, lb/d MUN, mg/dl 1No significant Forage*Protein interactions were observed (P > 0.60). USDFRC Effect of Dietary CP on the Lactation Curve (Wu & Satter, 2000) Symbol wk 1-16 15.4% 17.4% 17.4% 19.3% wk 17-44 16.0% 16.0% 17.9% 17.9% FCM 23,570b 25,640a 26,020a 25,480a Manure N 279c 309b 358a 355a USDFRC Strategies to Reduce N Excretion 1. Feed the Minimum Crude Protein (CP). 2. Accurately Track Dietary CP. 3. Use Model (e.g., NRC) to Meet Needs for RumenDegraded Protein (RDP) & Rumen-Undegraded Protein (RUP). 4. Reduce Rumen Degradability of Forage CP. 5. Feed “Complementary” RUP & Protected AA. 6. Use New Approaches to “Fine-Tune” Feeding. USDFRC Sampling Forage is Most Important USDFRC Changes in CP Over a 17-Week Trial Alfalfa silage Corn silage High moisture corn 48% Soybean meal 55 Crude protein, % of DM 50 25 10 5 1 3 5 7 9 11 13 15 17 USDFRC Week of Experiment Relationship of Dietary CP to MUN (Nousiainen et al., 2004) USDFRC Strategies to Reduce N Excretion 1. Feed the Minimum Crude Protein (CP). 2. Accurately Track Dietary CP. 3. Use a Ration Formulation Model (e.g., NRC) to Meet Needs for Rumen-Degraded Protein (RDP) & RumenUndegraded Protein (RUP). 4. Reduce Rumen Degradability of Forage CP. 5. Feed “Complementary” RUP & Protected AA. 6. Use New Approaches to “Fine-Tune” Feeding. USDFRC NRC (2001) Protein Model 1. Meet Microbial Needs for RDP. 2. Supply Metabolizable Protein to Meet Cow Needs with RUP. 3. Match Protein Quality to Cow’s Requirements (Not All RUP sources are Equal). USDFRC Matching Rumen Available Energy with RDP Get The Most Bang Out of Your Dietary Carbohydrate (But Not Too Much) USDFRC Effect of Processing on Digestion of Corn Starch (Owens et al., 1986) Processing Method Proportion of Starch Digestion, % Rumen Small Large Total Intestine Intestine tract 13 14 6 8 4 1 89 94 95 Cracked Corn 69 78 Ground Corn High Moisture Corn 86 USDFRC Rumen Ammonia & Production of Cows fed Alfalfa Silage & Ground HMEC (Ekinci & Broderick, 1997) 25 HMEC (4.3 mm) Milk Yield (lbs/day) 70 + 5.3 + 0.26 2.2 Protein Yield (lbs/day) Rumen ammonia, m M 20 65 2.0 15 60 1.8 Milk Protein HMEC Ground HMEC 10 5 Ground HMEC (1.7 mm) 0 0 6 12 18 24 USDFRC Time after feeding, h Effect of Replacing Alfalfa Silage with Concentrate (Valadares et al., 2000) 100 Milk & FCM yield & DM intake, lbs/day 90 3.5% FCM 80 Milk Fat & Protein yield, lbs/day 70 Fat Dry Matter Intake 3.5 60 3.0 50 Protein 2.5 40 20 35 50 65 2.0 USDFRC Dietary concentrate, % of DM Over-Feeding Grain Depresses Rumen pH & Milk Fat (Valadares et al., 2000) 6.75 3.75 Milk Fat Content, % Rumen pH 6.50 3.50 6.25 Rumen pH Milk Fat, % 20 35 50 65 3.25 6.00 3.00 USDFRC Dietary Concentrate, % of DM Lameness from Over-Feeding Grain Too Little Fiber in the Diet Results in Release of Histamine & Metalloproteinases, leading to Foot & Leg Damage. USDFRC Replacing Alfalfa Silage with Corn Silage (Brito & Broderick, 2003) Alfalfa Silage:Corn Silage 37:13 24:27 10:40 Item 51:0 Composition (% of DM) Alfalfa Silage Corn Silage Crude Protein Production DM Intake (lbs/d) Milk Yield (lbs/d) Rumen NH3 (mg N/dl) USDFRC 50.5 0 17.2 58.4a 91.5a 10.5a . . 37.1 13.3 17.0 57.1a 92.6a 10.0ab . . 23.6 26.7 16.8 55.1b 91.5a 8.7b . 10.2 40.0 16.6 51.1c 87.1b 6.2c . . a,b,c(P < 0.05) Feeding Sugar with Alfalfa Silage 1. Replacing Dietary Starch with ~2.5% Sugar Increased Intake, OM Digestibility & Fat Yield. 2. Reduced Rumen Ammonia. 3. Small Effects on Milk & Protein Yield. USDFRC Strategies to Reduce N Excretion 1. Feed the Minimum Crude Protein (CP). 2. Accurately Track Dietary CP. 3. Use Model (e.g., NRC) to Meet Needs for RumenDegraded Protein (RDP) & Rumen-Undegraded Protein (RUP). 4. Reduce Rumen Degradability of Forage CP. 5. Feed “Complementary” RUP & Protected AA. 6. Use New Approaches to “Fine-Tune” Feeding. USDFRC Harvest Alfalfa as Silage or Hay? USDFRC Mean Composition of Alfalfa Silage & Hay Item DM, % CP, % DM NPN, % CP Est. RDP, % CP NDF, % DM NEL, Mcal/kg DM Ash, % DM USDFRC Silage 41 20.6 51.9 71 38 1.51 10.4 Hay 86 18.1 8.0 73 38 1.50 9.8 Change, % ---12 -85 NS NS NS -6 Photo are nee Production on 50% Alfalfa Silage or Hay +/- Fish Meal (FM) Supplementation (Vagnoni & Broderick, 1997) +4.0 90 89.7 Alfalfa Silage +0.5 a Alfalfa Hay Alfalfa Silage + FM Alfalfa Hay + FM a 86.6 a 3.0 +0.22 2.80 b 85 a +0.04 a a 2.65 2.8 80 b 2.6 75 2.4 USDFRC Milk yield, lbs/day Protein, lbs/day Strategies to Reduce N Excretion 1. Feed the Minimum Crude Protein (CP). 2. Accurately Track Dietary CP. 3. Use Model (e.g., NRC) to Meet Needs for RumenDegraded Protein (RDP) & Rumen-Undegraded Protein (RUP). 4. Reduce Rumen Degradability of Forage CP. 5. Feed “Complementary” RUP & Protected AA. 6. Use New Approaches to “Fine-Tune” Feeding. USDFRC CP Supplement & Production (AS, CS, HMSC, 16.5% CP; Brito, 2004) Diets1 SSBM CSM Item Urea CM P>F ---------------(lbs/day)--------------DM intake Milk yield Milk protein Milk fat 1SSBM 48.7c 72.5b 2.03c 2.23c 53.4b 88.2a 2.71ab 2.69ab 54.5ab 89.3a 2.60b 2.60b 54.9a 90.6a 2.80a 2.84a < 0.01 < 0.01 < 0.01 < 0.01 = Solvent Soybean Meal; CSM = Cottonseed Meal; CM = Canola Meal a,b,c(P < 0.05) USDFRC CP Supplement & Omasal Protein Flows (Brito, 2004) Diets1 SSBM CSM Item RUP (“Bypass”) Microbial protein Total protein 1SSBM Urea CM P>F -----------------g/d-------------------538c 987b 1348a 1150ab <0.01 2706a 2706a 2775a 0.04 2344b 2882c 3693b 4054a 3925ab <0.01 = solvent soybean meal; CSM = cottonseed meal; CM = canola meal a,b,c(P < 0.05) USDFRC Strategies to Reduce N Excretion 1. Feed the Minimum Crude Protein (CP). 2. Accurately Track Dietary CP. 3. Use Model (e.g., NRC) to Meet Needs for RumenDegraded Protein (RDP) & Rumen-Undegraded Protein (RUP). 4. Reduce Rumen Degradability of Forage CP. 5. Feed “Complementary” RUP & Protected AA. 6. Use New Approaches to “Fine-Tune” Feeding. USDFRC Supplementing Rumen Protected-Met While Decreasing CP Item CP, % 18.6 RP-Met, g/d 0 Milk, lbs/d 87.7ab Milk/DMI 1.72ab Protein, lbs/d 2.54 MUN, mg/dl Milk N/NI, % 14.5a 26c 17.3 8 91.7a 1.80a 2.71 11.8b 30b 16.1 17 91.9a 1.77ab 2.71 9.4c 32b 14.8 25 87.5b 1.69b 2.65 7.9d 34a P>F 0.06 0.06 0.19 < 0.01 < 0.01 < 0.05) RP-Met = Mepron USDFRC a,b,c,d(P New Approaches to Consider 1. Protected Amino Acids • • • Rumen-Protected Met Sometimes Effective. Rumen-Protected Lys (Feeding with Corn Distillers). Other Possible Zero-N “Amino Acids” (RP-MHA). 2. Slow-Release RDP (Bugs Fed N at “Right Rate”) • • Slow-Release RDP from True Protein. Alfalfa Hay has Slow Release RDP vs. Alfalfa Silage. 3. Suppressing Rumen Protozoa • • USDFRC Protozoa Waste Protein but Improve Rumen Stability. Suppress Protozoa & Use Rumen Supplements. Same Milk for Less Crude Protein 1. More Profits, Less Pollution, Better Manure 2. How Much Over-Feeding of Protein is Risk Management (“Safety Margin”)? 3. How Low Can We go & Maintain Production? USDFRC