Effect of supplementation of a low-protein corn molt diet with amino acids on early postmolt laying hen performance

Commercial White Leghorn hens (69, 61, or 67 wk of age in Experiments 1, 2, and 3, respectively) were induced to molt by feed withdrawal until approximately 28% body weight loss occurred. All hens were then weighed, and seven replicate groups of 12 hens each were assigned to molt dietary treatments. Molt diets in Experiment 1 consisted of a corn basal diet (7.6% CP) or this diet supplemented with DL-Met, L-Lys, both Met and Lys, or a mixture of eight amino adds. In Experiment 2, L-Trp supplementation in addition to Met and Lys were evaluated, and in Experiment 3, L-Thr supplementation was also evaluated. Various levels of L-Glu supplementation were evaluated in all experiments, and a 16% CP corn-soybean meal diet was used as a positive control in all experiments. Six, seven, and five molt diets were fed for 16, 17, and 17 days and in Experiments 1, 2, and 3, respectively, and performance data were measured for 8 wk of production following initiation of feed removal. In all experiments, hens returned to egg production sooner and regained body weight faster when fed the 16% CP molt diet, compared with those fed the corn basal diet. In Experiment 1, supplementing the basal diet with Met and Lys together or with eight amino adds improved early egg production, egg yield, body weight gain, and feed efficiency compared with hens fed the basal diet. In Experiment 2, supplementation of Trp, Met, and Lys together slightly improved production performance compared with supplementation with only Met and Lys. The addition of Thr to the basal supplemented with Met, Lys, and Trp did not improve postmolt production performance factors in Experiment 3. Glutamic acid supplementation had no consistent effect on postmolt production. Thus, the present study indicated that supplementation of a low-protein corn molt diet with Met, Lys, and Trp enhanced early postmolt layer performance and yielded performance approaching that from the 16% CP diet. Amino add supplementation of a corn molt diet may be more economical than feeding a high-protein molt diet.