Effect of different levels of vitamin premix during finisher period on performance and carcass characteristics of broiler chicks fed wheat and barley based diet

In this experiment, the effect of different dietary vitamin premix levels was evaluated between 29 and 42 day of age on broiler chicken performance, and carcass characteristics in floor system. A total of 504 day-old male broiler chicks (Ross 308) were allocated to 7 treatment groups, with 4 replicates per treatment group and 18 birds per replicate pen. This experiment was a completely randomized design and the dietary treatments were: T1) the basal diet with no vitamin premix during at 29-42 days; T2) the basal diet 33.33% vitamin premix during 29-42 days; T4) the basal diet 66.66% vitamin premix during at 29-42 days and T6) 100% vitamin premix during at 29-42 days and treatments 3, 5 and 7 to 35 days, respectively, similar treatments 2, 4 and 6 and at age 36 days after treatment as a dietary were not vitamin premix. Feed intake and weight gain were measured at 35 and 42 days of ages and feed conversion ratio was calculated. Also, at 35 and 42 days of age, after slaughtered and measured carcass weight and percentage of thigh, breast, abdominal fat liver and heart. Results showed that different levels of vitamin premix did not impair performance and carcass characteristics during the final period of broilers (P>0.05). In conclusion, it is possible to withdraw vitamin premix from finisher diets.