Effect of Different Levels of Dietary Vitamin E on Broiler Breeder Performance and Humoral Immunity

Total numbers of 280 Arian broiler breeders were divided at random into seven experimental groups receiving graded levels of supplementary vitamin E (0, 20, 40, 60, 80, 100 and 120 IU/kg diet) between 26-35 weeks of age. Egg production, egg weight, fertility, livability and hatchability (30 and 35 weeks of age) were not influenced by the level of vitamin E in the breeder diet. But birds receiving 40 IU of vitamin E/kg diet had higher hatchability of fertile eggs compared to 0 and 20 IU of vitamin E/kg groups at 35 weeks of age (90.79% vs. 85.09% and 86.60%, respectively). Dietary levels of vitamin E did not affect antibody titer (IgG) against Newcastle disease virus at 35 weeks of age. Antibody titer of day old chicks from breeders receiving 60 IU of vitamin E/kg were higher (P≤0.05) than chicks from hens fed 0 and 20 IU of vitamin E. The results of this experiment suggest that the vitamin E requirement of broiler breeders for persisting of hatchability may be 40 IU/kg and for maximizing passive transfer of antibody from breeder to progeny may be higher.