The effect of vitamin premixes reduced or withdraw in wheat based finisher diet on performance, bone ash, and immunity response of broiler chickens

This experiment was carried out to study the effect of vitamin premix (VP) reduce/withdraw of finisher wheat based diet on growth performance, carcass efficiency, tibia bone ash, and humoral immune response of broiler chickens. Three hundred and fifty, one day-old male broiler chicks (Ross 308) were used in a complete randomized design (CRD) experiment with 7 treatments of 5 replicates and 10 birds each. The dietary treatments were: T1 (control), fed the basal diet containing 2.5g VP/kg of diet; T2, T3 and T4, The reduce dietary VP levels to 1.25 g/kg of diet from 25, 31 and 37 day of ages respectively; T5, T6 and T7, The complete withdrawal dietary VP from 25, 31 and 37 day of ages respectively. The results showed; reduced dietary VP levels to 1.25g/kg of diet from 25d of age did not impair effects on growth performance. The complete withdrawal dietary VP from 25d significantly decreased growth performance (P