Estimation of L-arginine requirement for Xinyang Black laying hens from 33 to 45 weeks of age

Abstract

The present study was conducted to estimate dietary L-arginine (Arg) requirement for the hybrid layers from 33 to 45 wk of age. Eight hundred and sixty-four 31-week-old Xinyang Black commercial laying hens were randomly allotted to 6 treatments with 4 replicates of 36 birds. The dietary treatments were corn-corn gluten meal based diets containing 0.64, 0.86, 1.03, 1.27, 1.42, and 1.66% L-Arg, respectively. Feed intake, egg weight, laying rate and FCR of layers responded quadratically (P < 0.05) to the increasing of dietary L-Arg levels; albumen height in 1.27% L-Arg group was the highest (P < 0.05) compared with that in other groups, and 1.27% L-Arg group had higher (P < 0.05) Haugh units than that in 0.64% and 0.86% L-Arg groups. Based on quadratic broken-line regression analysis, the L-Arg requirement of Xinyang Black laying hens (33 to 45 wk) was 1.26% and 1.25% of the diet for feed intake and egg weight, respectively.