Limiting amino acids in meat and bone and poultry by-product meals
| Autor: | Drew Shain, Mark Klemesrud, Terry J. Klopfenstein, Daniel Herold, Austin Lewis |
|---|---|
| Rok vydání: | 1998 |
| Předmět: |
Male
Meat Rumen Protein digestion Biology Weight Gain Feed conversion ratio Bone meal Poultry chemistry.chemical_compound Random Allocation Methionine Genetics Animals Urea Food science Amino Acids Poultry Products chemistry.chemical_classification Biological Products Minerals Sheep General Medicine Meat and bone meal Amino acid Diet chemistry Dietary Supplements Regression Analysis Animal Science and Zoology Cattle Dietary Proteins Digestion Food Science |
| Zdroj: | Journal of animal science. 75(12) |
| ISSN: | 0021-8812 |
| Popis: | In situ, digestion, and growth studies were conducted to evaluate four meat and bone meals and six poultry by-product meals as sources of escape protein and to predict the first-limiting amino acid for growing calves. Escape protein values, determined by 12-h in situ incubation, ranged from 41.7 to 51.0% of CP for meat and bone meals; poultry by-product meals ranged from 32.0 to 39.8%. True protein digestion in the gastrointestinal tract of lambs differed among protein sources (P < .05), ranging from 79 to 95%. In each of three growth trials, 60 steers (258 +/- 24, 241 +/- 23, and 230 +/- 16 kg for Trials 1, 2, and 3, respectively) were supplemented with 4 of the 10 protein sources along with a urea supplement. Protein sources were fed at 30, 40, 50, and 60% of the supplemental CP, with urea supplying the remainder. Protein efficiency differed among treatments ( P < .10), ranging from .61 to 1.55. Amino acid composition was determined for each protein source, and the individual metabolizable amino acids were regressed on the protein efficiency values. Escape protein values were correlated (R2 = .75) with protein efficiency but had a negative slope. Metabolizable methionine was the only amino acid moderately correlated (R2 = .40, slope = 1.9) to protein efficiency, whereas other amino acids either correlated poorly or had negative slopes. These data indicate that the protein value of meat and bone meal and poultry by-product meal is limited by the amount of metabolizable methionine they contain. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|