Abstract:

A 2×5 factorial experiment containing two CP levels(14%, 20%)and five threonine levels(0.5%, 0.58%, 0.66%, 0.74% and 0.82%) was conducted to evaluate the effects of different CP and threonine levels on feather development of starter Peking ducks. Four hundred and eighty onedayold male Peking ducks were randomly divided into 10 groups with 6 replicates in each group and 8 ducks in each replicate. These ducks were raised with experimental diets from 1 to 21 days of age. The results showed that threonine and CP in diets significantly affected the feather meat, one thousand downs weight, down length, one hundred plumages weight and plumages length(P<0.01). Dietary threonine levels from 0.74% to 0.82% did not affect feather reproduction rate, one thousand downs weight, down length, one hundred plumages weight and plumages length at higher dietary CP levels(P>0.05). However, dietary threonine levels from 0.74% to 0.82% significantly increased feather reproduction rate, one thousand downs eight, down length, one hundred plumages weight and plumages length at lower dietary CP levels(P<0.01). These results indicate that dietary threonine levels significantly affected feather development of starter White Peking ducks. Feather development need higher levels of threonine.