WHAT DO THE COWS HAVE TO SAY ABOUT NDF AND STARCH DIGESTION?

Transcription

1 WHAT DO THE COWS HAVE TO SAY ABOUT NDF AND STARCH DIGESTION? 2014 Ohio Nutrition Workshop Rock River Laboratory Dr. John Goeser, PAS & Dipl. ACAN Animal Nutrition and R&I Director Rock River Lab, Inc. Adjunct Asst. Professor University of WI Madison, Dairy Science

2 Agenda: 45 Min. Industry Outlook Nutrition/Ration program aim & utility Basic levels used to assess nutrient utilization Better using digestion coefficients within rations What do the cows have to say? The next 15 years

3 Industry Outlook (CIH, 2014) Margin Focus Adapted from CIH Group. Accessed online Dec 2,

4 Nutrients and Nutrition Nutrients are those that furnish nourishment (Miriam-Webster, 2014 accessed online) CP, carbohydrates and fat are nutrients 9.4, 4.2 and 5.6 calories per g, respectively (NRC, 2001) Calories make milk NDF = Starch???? Image source: crossfitrebels.com

5 CHO Digestion impact on milk New Crop corn silage and HMSC? 10 unit less diet rumen starch digestion 10 lbs. less milk (e.g vs lb./cow) 150 g less microbial CP Substantial change in new crop CS/Hlg NDFD? 10 unit change in diet TTNDFD 11 lbs. less milk (e.g vs 81.6 lb./cow) 127 g less microbial CP Estimated with modified NRC (1989; 2001) equations How do we better forecast these responses? Milk image source:

6 Carbohydrate Digestibility Affects Health & Production Properly balancing NFC and NDF is critical for health and production in high producing dairy cows. Variations in fiber digestibility affect production more than variations in starch digestibility Starch digestibility => 3-5 lb/day Fiber digestibility => 6-7 lb/day

7 Nutrition Program Aim Energy (calories) can be considered a nutrient How do we get there? Nutrient % (CP, NDF, etc) Nutrient Digestibilities (NDFD, etc) Total Digestible Nutrients, TDN ME or NE L Weiss, 1998 Weiss, 1998

8 Digestion Coefficients Challenging aspect to ruminant nutrition Which NDFD or Starch D time point?!?

9 Factors Affecting Digestion Seed / genetics Dry matter content Growing environment Fermentation / preservation Crop / feed processing Rumen dynamics Interactions with other ingredients Passage rate Dry matter intake Production level / stage Body size Forage to Concentrate ratio Etc

10 Where does nutrient k d fit? Nutrient % (CP, NDF, etc) Nutrient Digestibilities (NDFD, etc) Total Digestible Nutrients, TDN ME or NE L

11 Think of k d & dig. Nutrient Pool size like fuel economy (Combs, pers. comm.)

12 Rumen Works the Same! Same NDF k d (fuel economy) Different digestible Pool sizes (tank).3 liters performance! Different NDF k d (fuel economy) Same digestible Pool sizes (tank) Also 3 liters performance!

13 Diet forecast starts with a practical digestion measure 1. Lab bench rumen and intestinal in vitro Meaning outside the body (Miriam-Webster, 2014) 2. Rumen or intestinal incubation rumen/intestinal in situ Meaning in the natural or original position (Miriam- Webster, 2014) 3. Through the animal in vivo Meaning in the living body (Miriam-Webster, 2014)

14 Diet forecast starts with a practical digestion measure

15 Rumen or intestinal in vitro digestion

16 Rumen in situ digestion

17 Cow level in vivo digestion

18 Now what? How do we use digestion results within ration models? Can we improve ration performance? What do the cows have to say?

19 Ration Model Approaches Empirical Models e.g. NRC (2001) TDN1x = dcp x dfat + dnfc + dndf -7 d is the digestibility coefficient Based on prior data Mechanistic Models e.g. CNCPS (Tylutki et al., 2008) TDN = dcpa 1 + dcpa 2 + d d determined with pool size, k d and k p measures

20 Formulating with CHO Digestion results Two core theories Empirical: NRC (2001) Biology or similar Old Book values Recent - 48 h in vitro digestion and other regression values Future??? Mechanistic: CPM, CNCPS Biology or similar Old Book CHO k d and pool size values More recent Lab measured CHO k d and pool sizes Future??? The next 15 years?

21 What do Cows have to say? Meta-Analyses summary from those reporting in vivo digestion results for lactating cattle (Goeser, 2014) Description Nutrient Animal Type Digestion Site Author(s) Treatment Digestion means Coefficient, % SD Mixed TMRs NDF Lactating Dairy Cow Rumen Firkins et al. (2001) Mixed TMRs NDF Mixed Rumen Hannigan et al. (2013) Corn silage based TMRs NDF Lactating Dairy Cow Rumen Ferraretto and Shaver (2012) NA TMRs containing barley based grain NDF Lactating Dairy Cow Rumen Ferraretto et al. (2013) NA TMRs containing corn based grain NDF Lactating Dairy Cow Rumen Ferraretto et al. (2013) NA n or Weighted means NDF Rumen Alfalfa and Grass Forage based TMRs NDF Lactating Dairy Cow Total Tract Goeser (2008) Corn and Sorghum Forage based TMRs NDF Lactating Dairy Cow Total Tract Goeser and Combs (unpublished) Mixed TMRs NDF Lactating Dairy Cow Total Tract Firkins et al. (2001) Mixed TMRs NDF Mixed Total Tract Hannigan et al. (2013) TMRs NDF Mixed Total Tract Krizsan et al. (2010) Corn silage based TMRs NDF Lactating Dairy Cow Total Tract Ferraretto and Shaver (2012) NA TMRs containing barley based grain NDF Lactating Dairy Cow Total Tract Ferraretto et al. (2013) NA TMRs containing corn based grain NDF Lactating Dairy Cow Total Tract Ferraretto et al. (2013) NA n or Weighted means NDF Total Tract Mixed TMRs Starch Lactating Dairy Cow Rumen Firkins et al. (2001) Mixed TMRs Starch Mixed Rumen Hannigan et al. (2013) Corn silage based TMRs Starch Lactating Dairy Cow Rumen Ferraretto and Shaver (2012) NA TMRs containing corn based grain Starch Lactating Dairy Cow Rumen Ferraretto et al. (2013) NA TMRs containing barley based grain Starch Lactating Dairy Cow Rumen Ferraretto et al. (2013) NA n or Weighted means Starch Rumen Mixed TMRs Starch Lactating Dairy Cow Total Tract Firkins et al. (2001) Mixed TMRs Starch Mixed Total Tract Hannigan et al. (2013) Corn silage based TMRs Starch Lactating Dairy Cow Total Tract Ferraretto and Shaver (2012) NA TMRs containing barley based grain Starch Lactating Dairy Cow Total Tract Ferraretto et al. (2013) NA TMRs containing corn based grain Starch Lactating Dairy Cow Total Tract Ferraretto et al. (2013) NA n or Weighted means Starch Total Tract

22 What do Cows have to say? TMR - Fiber - Starch Rumen in vivo NDF = 42.0 ± 24 Starch = 59.3 ± 31 Total Tract in vivo NDF = 48.5 ± 22 Starch = 92.4 ± 6.5 (Goeser, 2014)

23 How accurate are we NDFD? Rumen NDFD (30 h) = TMR reality based on in vivo meta-analysis = Legume traditional in vitro = Corn silage traditional in vitro Rumen NDF Digestion, % of Nutrient

24 How Accurate Are We NDFD? Total Tract NDFD (30 h) = TMR reality based on in vivo meta-analysis = Forage TTNDFD (Combs, 2013) Total Tract NDF Digestion, % of Nutrient

25 Typical NDF and TTNDFD values Forage NDF Average High Low TTNDFD TTNDFD TTNDFD Alfalfa < 40% 42% > 48% < 36% Corn Silage < 40% 42% > 48% < 36% Grasses < 45% 42% > 48% < 36% A 2-3 unit change in ration TTNDFD corresponds to a one pound change in milk yield.

26 TTNDFD further Validated TTNDFD Adapted and from associated Goeser et al. model (2014) inputs are related to dairy cattle digestion measures Lopes et al. (2014) and Goeser et al. (2014) separately validated TTNDFD measures Adapted against from Lopes total et al. tract (2014) in vivo measures Lopes et al.: in vivo TTNDFD = *in vitro TTNDFD Slope P < 0.001, R 2 = 0.61 Goeser et al.: in vivo TTNDFD = *in vitro TTNDFD Slope P < 0.01, R 2 = 0.30

27 2014 Crop Year Silage?

28 How accurate are we Starch D? Rumen Starch D results summary = TMR reality based on in vivo meta-analysis = predicted using k d from 7 h in situ data = predicted using k d from 7 h in vitro data Rumen Starch Digestion, % of Nutrient

29 What Are Real Rumen 7 h Starch D Values? Opportunities? Estimates based on rumen potentially digestible starch values from meta-analysis dataset and assuming 5%, 20% and 35% / h Starch k d for Low, Avg and Max scenarios, respectively.

30 Capturing Starch D Opportunities Heuer, 2014 M.S. Thesis

31 Formulating with CHO Digestion results Two core theories Empirical: NRC (2001) Biology or similar Old Book values Recent - 48 h in vitro digestion and other regression values Future Cow-level validated digestion coefficients TTNDFD (Combs, 2013) Rumen and T.T. starch digestion Mechanistic: CPM, CNCPS Biology or similar Old Book CHO k d and pool size values More recent Lab measured CHO k d and pool sizes Future More robust pool size, k d and k p measures NDF and now Starch The next 15 years? Better agree with what cows say

32 Mechanistic model opportunities?

33 Mechanistic model opportunities?

34 Empirical model opportunities?

35 Contact John Goeser, PhD PAS Office: on Twitter

36 References Combs, D.K TTNDFD: A new approach to evaluate forages. Proc Cornell Nutrition Conference for Feed Manufacturers. Syracuse, NY. Goering, H. K., and P. J. Van Soest Forage fiber analyses. Apparatus, Reagents, Procedures and Some Applications. In U. S. G. P. Office Agricultural Handbook No Agricultural Research Services, U.S. Dep. Agric. Washington, DC. Goeser, J.P Comparing new crop corn silage to old crop What might cause the new crop slump? Proc California Animal Nutr. Conf., Fresno, CA. Goeser, J.P What do the cows have to say about NDF and starch digestion? Proc Four State Dairy Nutrition and Management Conference. Dubuque, IA. pg Goeser, J.P, and C.R. Heuer Total tract NDF digestion predicted using rumen in vitro measures is related to commercial dairy in vivo total tract nutrient digestion. J. Dairy Sci. Vol. 97, E- Suppl. 1. Pg 775 Heuer, C.R Masters of Science Thesis. University of Wisconsin-Madison. Lopes, F. K. Ruh, D.K. Combs, L.F. Ferraretto, S.M. Fredin, C. Arndt, R.D. Shaver and L.E. Armentano Validation of a new approach to estimate total tract fiber digestibility from in vitro NDFD values. J. Dairy Sci. Vol. 97, E-Suppl. 1 pg National Research Council Nutrient Requirements of Dairy Cattle, 6th Revised Ed. National Academy Press, Washington, D.C. National Research Council Nutrient Requirements of Dairy Cattle. 7th Revised ed. National Academy Press, Washington, D.C. Tylutki, T.P., D.G. Fox, V.M. Durbal, L.O. Tedeschi, J.B. Russell, M.E. Van Amburgh, T.R. Overton, L.E. Chase and A.N. Pell Cornell net carbohydrate and protein system: A model for precision feeding of dairy cattle. Anim. Feed Sci. Tech. 143: Weiss, W.P Estimating the available energy content of feeds for dairy cattle. J Dairy Sci. 81:

37 Meta-analysis references Ferraretto, L.F. and R.D. Shaver Meta-analysis: effect of corn silage harvest practices on intake, digestion and milk production by dairy cows. Prof. Anim. Sci. 28: Ferraretto, L.F., P.M. Crump, and R.D. Shaver Effect of cereal grain type and corn grain harvesting and processing methods on intake, digestion, and milk production by dairy cows through a meta-analysis. J. Dairy Sci. 96: Firkins, J.L., M.L. Eastridge, N.R. St-Pierre, and S.M. Noftsger Effects of grain variability and processing on starch utilization by dairy cattle. J. Anim. Sci. 79(E. Suppl.):E Goeser, J.P Improvement of rumen in vitro NDF digestibility techniques and data analysis. PhD thesis. University of Wisconsin Madison, Madison, WI. Hannigan, M.D., J.A.D.R.N. Appuhamy, and P. Gregorini Revised digestion parameter estimates for the Molly cow model. J. Dairy Sci. 96: Krizsan, S. J., S. Ahvenjärvi, and P. Huhtanen A meta-analysis of passage rate estimated by rumen evacuation with cattle and evaluation of passage rate prediction models. J. Dairy Sci. 93: