Deficient Amino Acids in a 22% Protein Corn-Soybean Meal Diet for Young Turkeys

Three similar poult experiments were conducted to determine which amino acids are most deficient in a 22% protein corn-soybean meal diet supplemented with .3% DL-methionine. Diets were formulated to contain 1) 30% protein, 2) 22% protein, and 3) 22% protein plus all essential amino acids. Nine additional diets consisted of the latter diet excluding at least one added essential amino acid. All diets were fed to poults from 8 to 18 or 20 days of age. Removing either valine, lysine, threonine, or isoleucine from the amino acid mixture significantly reduced (P<.05) body weight gain by 9.3, 8.0,6.0, and 4.1%, respectively. These reductions, however, were not as great as the 13.9% reduction obtained by feeding the unsupplemented 22% protein diet. Results indicate that the 22% protein corn-soybean meal diet may be more deficient in nitrogen for nonessential amino acid production than in any one essential amino acid.