The effect of L-lysine intake on egg component yield and composition in laying hens

Currently, 24% of the total U.S. egg supply is consumed as liquid egg product (LEP). In addition to egg weight and size, the commercial value of LEP is a function of percentage solids. The influence of L-Lys on LEP, the texture profile analysis of heat formed albumen and yolk gel plugs, and yolk emulsion separations was examined in two experiments. In Experiment 1, 108 layer hens (42 wk of age) were fed three sorghum-soybean diets with Lys levels ranging from 677 to 1,613 mg per hen per d (mg/HD). In Experiment 2, 108 layer hens (23 wk of age) were fed four sorghum diets with Lys levels ranging from 638 to 1,165 mg/HD. In Experiment 1, Lys intake of 1,613 compared to 677 mg/HD significantly increased albumen weight, solids, and protein and egg weight. There were no significant differences in egg production, feed consumption, or yolk weight, protein, and solids. In Experiment 2, Lys intake of 1,165 mg/HD resulted in significantly lower feed consumption, nutrient intake, and egg production. Lysine intake of 1,062 compared to 638 mg/HD resulted in significantly greater albumen solids, protein, and hardness, and egg production. Lysine intake of 828 compared to 638 mg/HD resulted in significant increases in yolk weight, protein, hardness, and emulsion separations. Lysine intakes of 1,062 mg/HD resulted in most yolk parameters returning to levels observed at 638 mg/HD. There were no significant differences in egg weight or yolk solids. This increased understanding of the influence of L-Lys on LEP parameters offers economic benefit to liquid egg producers.