This experiment was conducted to evaluate effects of dietary methionine levels on growth performance,serum biochemical parameters,carcass performance and development of some organs,and determine the methionine requirement of Lueyang Black-boned Chickens aged from 13 to 18 weeks.Six hundred Lueyang Black-boned chickens at 12-week-old were selected,with 300 male and 300 female separately fed and randomly divided into five groups,each six replicates of 10 chickens.A single factorial experiment containing 5 methionine levels (0.22％,0.32％,0.42％,0.52％ and 0.62％) was undergone.The results showed as follows:1) Different methionine levels had significant effects on the average daily intake (ADFI) of 13 to 15 week-old female chickens (P＜0.05),the feed/gain (F/G) of 13 to 15 week-old male chickens was significantly affected by the methionine levels (P＜0.05).When methionine levels were 0.32％-0.42％ the F/G of male and female chickens were lower than that in other groups.In addition,different methionine levels had no significant effects on the F/G of 16 to 18 week-old male and female chickens (P＞0.05).Furthermore,different levels of methionine affected the F/G of 13 to 18 week-old male chickens (P＜0.05),while no significant effects on the female (P＞0.05).Compared with other treatment groups,the minimum F/G of 13 to 18 week-old male and female chickens was in the treatment group 2 (0.32％).2) There were no significant effects on the serum biochemical parameters of 13 to 18 week-old male and female chickens (P＞0.05).3) Methionine levels had significantly effects on the eviscerated rate and breast muscle percentage of 13 to 1 8 week-old male chickens (P＜0.05).Compared with other groups,the eviscerated rate of treatment group 2 (0.32％) was highest.The carcass performance of female chickens was not affected significantly by the methionine levels (P＞0.05).4) Different levels of methionine had no significantly effects on the development of internal organs,immune organs as well as some digestive organs (P＞0.05).In conclusions,the dietary methionine levels in the range of 0.32％-0.42％ were suggested for 13 to 18 weeks Lueyang Black-Boned chickens.
国家科技期刊平台
NSTL
维普
万方数据
