Performance of Commercial Laying Hens Fed Various Supplemental Amino Acids in a Corn-Soybean Meal Diet

Abstract

Two experiments using Hy-Line® W36 pullets, 26 wk of age, helped determine their lysine (Lys) requirement and the next limiting amino acid in a corn-soybean diet. Corn-soybean meal diets ranging from 16.68 to 13.79% protein were fed in Experiment 1. All diets contained supplemental methionine (Met). The diets were fed with and without supplemental Lys. When unsupplemented diets were fed, Lys intake ranged from 754 to 502 mg/hen/day. The daily Lys requirement was 685.7, 677.4, and 755 mg/hen/day for egg mass (EM), egg production (EP), and egg weight (EW), respectively. When the diet provided less than 560 mg/hen/day of Lys, supplemental Lys did not restore EP. This finding indicated that another amino acid was limiting.In Experiment 2, various combinations of supplemental tryptophan (Trp), arginine (Arg), threonine (Thr), isoleucine (Ile), valine (Val), and glutamic acid (Glu) were fed. Hens receiving the negative control diet during 31-34 wk had daily intakes of 540, 505, 668, 395, 115, 426, 480, and 1968 mg/hen/day total sulfur amino acids (TSAA), Lys, Arg, Thr, Trp, Val, Ile, and Glu, respectively. Supplementing the diet with Met and Lys significantly increased EM. Further improvement in EM resulted from the combination of Thr, Arg, and Trp supplementation. The addition of Val to the diet with Met, Lys, Thr, Arg, and Trp significantly increased EM. However, the addition of Ile was without benefit in the presence or absence of Val. Egg mass was not significantly increased with a diet that contained all amino acids, with Val becoming next limiting after these. In a corn soybean meal diet Met is the first limiting EAA, followed by Lys. Trp and Arg are the next limiting, followed by Val.