Abstract
The experiments were conducted to investigate the effects of supplementary feather meal(FM) and its digest on the taurine content and performance of laying hens. Feeding trial was conducted with 810 78-wk-old ISA-Brown layers for 5wk. The experiment consisted of nine dietary treatments ； T1 ; control(basal diet), T2；Tl + feather meal(FM) 6 ％ diet, T3；T2 + pyridoxin(21 mg/kg) supplemented diet, T4； T1 + H$_2$O$_2$treated FM 6%, T5； T4 + pyridoxin(21 mg/kg) supplemented diet, T6； T1 + cystine(0.25 ％) supplemented diet, T7； T6 + pyridoxin(21 mg/kg) supplemented diet, T8； T1 + synthetic taurine supplemented(0.25％) diet, T9； T1 + synthetic taurine supplemented(0.5 ％) diet. Diets were formulated to be iso-caloric and to meet NRC(1994) requirements of essential nutriente. Birds in treatments T3 showed significantly higher(P＜0.01) egg production, feed intake, feed conversion ratio, egg weight, haugh unit and eggshell strength than those fed other treatments. Supplementation of FM. H$_2$O$_2$treated FM and cystine with or without pyridoxin did not significantly affected taurine content of egg yolk. Only synthetic taurine supplemented diets(T8 and T9) linearly increased(P＜0.01) taurine content of egg yolk.