Challenges of Predicting Metabolizable Lysine Content of Ingredients

Transcription

1 Challenges of Predicting Metabolizable Lysine Content of Ingredients Sarah Boucher William H. Miner Agricultural Research Institute Pre-Conference Symposium 71 st Annual Cornell Nutrition Conference East Syracuse, NY October 20 22, 2009

2 Presentation 1. Lysine structure 2. Nutritional consequences of heat processing 3. Estimating lysine damage in the RUP fraction of feeds 4. Digestibility of lysine and RUP in blood meal 5. Summary

3 20 Amino acids Indispensable 1. Arginine 2. Histidine 3. Isoleucine 4. Leucine 5. Lysine 6. Methionine 7. Phenylalanine 8. Threonine 9. Tryptophan 10. Valine Dispensable 1. Alanine 2. Aspartic acid 3. Asparagine 4. Cysteine 5. Glutamic acid 6. Glutamine 7. Glycine 8. Proline 9. Serine 10. Tyrosine

4 Amino Acid Structure α-amino group R 1 O + H 3 N α C C H O

5 Peptide Bond Formation R 1 O R 2 O + H 3 N C H C O H O H + H 3 N C H C O R 1 C O C N R 2 + H 3 N C H H H C O O

6 Lysine Structure NH 2 CH 2 CH 2 CH 2 CH 2 O H 2 N C H C O

7 Protein metabolism in ruminants Crude protein Saliva True protein Peptides NPN Urea RUMEN Amino acids Ammonia Liver RUP Microbial protein Amino acids SMALL INT RUP Microbial protein Endogenous protein Mammary gland Metabolizable protein (absorbed AA) MILK

8 Characteristics of Lysine Cationic amino acid at physiological ph In direct competition with arginine for intestinal absorption Absorption stimulated by intracellular leucine - S. Bröer Physiol Rev 88:

9 Intestinal Lysine Absorption y+l b o,+ Adapted from: S. Bröer Physiol Rev 88:

10 Lysine Structure

11 Heat Processing Reactions 1. Amino acid racemization 2. Protein cross-linking reactions 3. Maillard reaction

12 Maillard Reaction Generally has the greatest impact on nutritional quality of feeds 3 phases: 1. Early 2. Advanced 3. Final

13 Simplified Scheme of Maillard Reaction Reducing sugar + Amino compound Amadori compound Advanced glycation end products Melanoidin formation Adapted from J. Mauron Prog. Fd. Nutr. Sci. 5:5-35.

14 Challenges with Lysine Analysis H 2 N CH COOH (CH 2 ) 4 NH CH Boiling 6N HCl 24 h C = O (HCOH) 3 CH 2 OH Amadori compound

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16 Terminology Bioavailability proportion of ingested dietary AA that is absorbed in a chemical form that renders these AA potentially suitable for metabolism or protein synthesis Digestibility reflects enzymatic hydrolysis of ingested proteins and absorption of AA and peptides from the gastointestinal lumen

17 Terminology Basal endogenous AA losses - the minimum quantities of AA inevitably lost by the animal Standardized digestibility calculated by subtracting only basal endogenous AA losses from outflow of AA

18 Estimating Intestinal AA Digestibility In Vivo Ruminant Digestive Tract Avian Digestive Tract

19 Standardized Digestibility SBM Products Standardized digesitbility, % c b a a a a c b a a a a HSP HSBM SP2 SP3 SBM2 SBM RUP-Lysine RUP-Total AA SE = 2.9 SE = 1.7 a,b,c Means within a series with different superscripts differ, P < 0.01

20 Standardized Digestibility - DDGS Standardized digestibility, % c b a a,b a,b b a a a a HDDGS DDGS1 DDGS2 DDGS3 DDGS4 0 RUP-Lysine RUP-Total AA SE = 2.93 SE = 1.28 a,b,c Means within a series with different superscripts differ, P < 0.01

21 Standardized Digestibility Fish meals a a a a a a a a Standardized digestibility, % b b ANVY CFSH MNHN1 MNHN2 PLCK 10 0 RUPLysine RUP-Total AA SE = 1.88 SE = 1.44 a,b,c Means within a series with different superscripts differ, P < 0.01

22 Terminology Blocked lysine lysine molecules in which the ε-amino group is bound to another compound Reactive lysine lysine molecules in which the ε-amino group is not bound to another compound

23 Estimating Blocked RUP-Lys H 2 N CH COOH (CH 2 ) 4 NH CH Boiling 6N HCl 24 h C = O (HCOH) 3 CH 2 OH fructosyllysine

24 Estimating Reactive RUP-Lys NH 2 CH 2 CH 2 H 2 N O C CH 3 NH NH CH 2 CH 2 C NH 2 NH CH 2 CH 2 H 2 N CH 2 C COOH H 2 N CH 2 C COOH H H Lysine Homoarginine

25 Modified TSP Gargallo et al. (2006) 5 g of rumen undegraded resiude weighed into polyester bags in duplicate Incubated in a pepsin/hcl solution 1 h, 38 C Incubated in a pancreatin solution 24 h, 38 C Bag residues analyzed for AA Gargallo et al. (2006) J. Anim. Sci. 84:

26 Lysine Estimates Soy-products Sample Furosine Blocked RUP-Lys, % Method Homoarginine MTSP Rooster Reactive RUP-Lys, % RUP-Lys digestibility, % RUP-Lys digestibility, % Heated SP SP SP Heated SBM SBM SBM

27 Lysine Estimates DDGS Sample Furosine Blocked RUP-Lys, % Method Homoarginine MTSP Rooster Reactive RUP-Lys, % RUP-Lys digestibility, % RUP-Lys digestibility, % Heated DDGS DDGS DDGS DDGS DDGS

28 Lysine Estimates Fish meal Sample Furosine Blocked RUP-Lys, % Method Homoarginine MTSP Rooster Reactive RUP-Lys, % RUP-Lys digestibility, % RUP-Lys digestibility, % ANVY CFSH MNHN MNHN PLCK

29 Sample Blood meal Homoarginine Reactive RUP-Lys, % Method MTSP 1 MTSP 2 Rooster RUP-Lys digestibility, % RUP-Lys digestibility, % RUP-Lys digestibility, % Heated bovine BM Bovine BM Bovine BM Heated porcine BM Porcine BM Porcine BM

30 Ohio State Modifications of the Three-Step Procedure 1. Foundation for the procedure is the Calsamiglia and Stern (1995) Minnesota three-step procedure 2. Modifications minimized inter assay variation to 5% 3. Validated by Nostfsger and St-Pierre (2003, J. Dairy Sci. 86: ) lactational performance trial 4. Patent pending procedure is intellectual property of Venture Milling

31 Blood Meal RUP digestibility n = 403 Blood meal RUP digestibility RUP digestibility % RUP (%CP) Average RUP digestibility, % = 64.6; SE = 23.1 Data courtesy of Venture Milling. Ring dried blood meal data generated from non-published Ohio State University research using a Modified Minnesota 3-Way analytical procedure.

32 Blood Meal RUP-Lysine Digestibility n = 403 Blood meal RUP lysine digestibility vs RUP digestibility RUP Lys digestibility RUP digestibility Average RUP- Lys digestibility, % = 56.0; SE = 27.1 Data courtesy of Venture Milling. Ring dried blood meal data generated from non-published Ohio State University research using a Modified Minnesota 3-Way analytical procedure.

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34 NRC Crude Protein Fractions Feed Crude Protein Fraction A NPN Fraction B Rest of CP Fraction C Undegraded NRC, 2001

35 RUP digestibility, NRC (2001) RUP digestibility values are the approximate mean values reported using the mobile bag technique and the three step procedure Assumes digestibility of individual AA in RUP is the same as RUP

36 CNCPS Crude Protein Fractions TOTAL BORATE BUFFER NEUTRAL DETERGENT ACID DETERGENT SOL A INSOL SOL A INSOL SOL A INSOL B1 B2 B3 B1 B2 B3 B1 B2 B3 C C C

37 RUP digestibility, CNCPS v.6.1 Absorption of escaped feed protein is calculated by multiplying each protein fraction by its respective intestinal digestibility A 100% B1 100% B2 100% B3 80% C 0% Assumes digestibility of individual AA in RUP is the same as RUP

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39 Ingredient % of DM Corn silage 36.8 Grass silage 16.1 Alfalfa hay 5.8 Corn grain 10.7 Soybean hulls 5.0 Soybean meal 2.1 DDGS 10.7 Soybean meal, expellers 2.3 Blood meal 1.3 Rumen protected Met 0.05 Urea 0.25 Inert fat 1.1 Vitamins/minerals 2.5 Example diet Balanced in NRC (2001) Animal: ~ 85 lbs milk DMI = 53 lbs

40 NRC (2001) Library DDGS Blood meal ring-dried RUP, % CP* RUP digestibility, % Lys, % CP *At DMI = 4.0% of BW and DMI = 50% forage

41 RUP-Lys digestibility Scenario 1: DDGS RUP-Lys digestibility = 63% Blood meal RUP-Lys digestibility = 56% Scenario 2: DDGS RUP-Lys digestibility = 80% Blood meal RUP-Lys digestibility = 90%

42 Example NRC (2001) Scenario 1 Scenario 2 Lys, % of MP Met, % of MP Lys: Met 3.0:1 2.89:1 3.04:1

43 Summary Heat processing of feeds can damage lysine Intestinal digestibility of lysine in the RUP fraction of heated feeds is less than digestibility of total RUP Determining digestible or available lysine content of feeds can improve predictions of MP-Lys supply

44 Acknowledgements Special thanks to Venture Milling and Normand St-Pierre Financial support for some of the research presented was provided by: Adisseo West Central Special thanks to research collaborators Carl Parsons Pam Utterback Hans Stein Sergio Calsamiglia Marshall Stern Carsten Pedersen Lawrence Novtony & Deon Simon at SDSU