The effect of grower diet protein level on the performance and some slaughtering characteristics of sex-separated and mixed-sex broilers.

摘要

This trial examined 1350 sex-separated broilers at 24 days of age. Chicks were fed a standard broiler starter diet for the first 21 days. Isocaloric grower diets (16.84, 18.00 and 19.46% crude protein, respectively) were offered to broilers housed in sex-separated and mixed-sex pens from days 24 to 45 of the experimental period. It was shown that while the body weights of sex-separated and mixed-sex broilers were similar, dietary protein level and sex had a significant effect on the body weight of broilers during the experimental period (P<0.01). Male broilers consumed more feed and had better feed conversion than females (P<0.01). However, separate sex rearing had no significant effect on feed consumption or feed conversion rate (P>0.05). As dietary protein level decreased, feed consumption increased numerically and feed conversion was negatively affected (P<0.01). The percent rate of carcass yield, breast, thigh, abdominal fat pad, liver and gizzard was not affected by the dietary protein treatment (P>0.05), but females had heavier abdominal fat and gizzard than males (P<0.01). Some slaughtering characteristics determined in the study were not affected by the broiler rearing methods. In conclusion, rearing male and female broilers separately has no significant effect on their performance. Neither sex had a tolerance to protein deficiency in the growing diets. Therefore, these results do not support the idea of feeding male and female broilers nutritionally different diets based on protein levels.