Effect of Dietary Fat and Protein on Performance, Egg Composition, Egg Solids, and Egg Quality of Hy-line W-36 Hens During Phase 1

A 4X3 factorial experiment with four dietary fat levels and three protein levels was conducted to determine the influence of dietary fat on performance, egg composition, egg solids, and egg quality of Hy-line W-36 hens at different protein levels. This experiment lasted 16 weeks. Hy-line W-36 hens (n = 1440) in phase 1 (21 weeks of age) were randomly divided into 12 treatments (8 replicates of 15 birds per treatment). There was no significant interaction on all parameters between protein and dietary fat. Protein had a significant effect on egg weight, egg mass, feed conversion, albumen weight, percent whole egg solids, and yolk color. Dietary fat had a linear effect on feed intake. As dietary fat increased from 0 to 3.35%, feed conversion linearly improved. A further increase of dietary fat from 3.35 to 5.04% had no additional effect on feed conversion. There was no significant difference in egg specific gravity among hens fed diets supplemented with 0%, 1.67% and 3.35% fat levels. Increasing dietary fat from 3.35 to 5.04% significantly decreased egg specific gravity. As protein increased, albumen weight significantly increased and percent whole egg solids significantly decreased. Increasing dietary fat significantly increased percent yolk, yolk/albumen ratio and percent whole egg solids, but decreased percent albumen. Based on feed conversion and egg specific gravity, the addition of 3.35% fat might be sufficient for optimal performance and egg quality of Hy-line W-36 hens during phase 1.