This Is AuburnElectronic Theses and Dissertations

Effect of Dietary Energy, Protein, Lysine, Versatile Enzyme, And Peptides on Commercial Leghorns




Gunawardana, Priyantha

Type of Degree



Poultry Science


Two experiments were conducted to determine the effect of increasing dietary lysine on performance, egg composition, egg solids, egg quality, in seven commercial brown egg layer strains, and to determine the nutrient (lysine) requirements that allow for the best performance in phase one and two. Lysine had significant effects on egg weight, egg mass, feed conversion, percent albumen solids, yolk color, shell color, albumen weight, egg shell and albumen components. There were significant strain effects on egg production, feed consumption, egg weight, egg mass, feed conversion, specific gravity, yolk weight, shell color, shell, albumen and yolk components, yolk, albumen and whole egg solids. All strains peaked in production over 94% and were laying 94 to 96% at 36 weeks of age. Average egg weight (21wk to 36wk) was 60.3g, varying from 59.0 to 62.8 g between strains. Average feed intake was 112.3g/hen/day varying from 109.6 to 116.7g/hen/day between strains. Increasing dietary lysine from 0.747 to 0.917% significantly improved feed conversion from 2.20 to 2.06 g feed/g egg and increased egg mass from 51.8 to 54.32 g/hen/day. Average lysine intake of hens fed 0.917% level was 1023mg/hen/day varying from 1005 to 1070mg/hen/day between strains. During phase two, increasing dietary lysine increased egg production, egg weight, egg mass and improved feed conversion as observed in phase one. However, increasing dietary lysine increased feed consumption during phase two. Increasing dietary lysine from 0.680 to 0.828% significantly improved feed conversion from 2.03 to 1.91 g feed/g egg and increased egg mass from 54.0 to 59.30 g/hen/day. Average lysine intake of hens fed 0.828% level was 939 mg/hen/day varying from 907 to 964 mg/hen/day between strains. Because egg and ingredient prices often change, there can be no fixed dietary lysine level for optimal profits. Protein had a significant effect on egg production, egg mass, feed intake, feed conversion, egg weight, percentage of egg shell components, yolk color , and yolk and albumen weight. Increasing dietary energy to 238 kcal ME/kg by addition of poultry oil, feed intake linearly decreased. Increasing dietary energy also significantly increased body weight and egg yolk color.