THE EFFECT OF SUPRAPHYSIOLOGICAL DOSES OF VITAMIN E ON PERFORMANCE OF BROILER BREEDERS FLOCK

: The effect of supplementary vitamin E levels on the performance of broiler breeder flocks was studied. A completely randomized design with four treatments (100, 500, 1000, or 1500 IU vitamin E/kg) and three replicates per treatment was used. Each replicate included seven females and one male broiler breeder. Rearing conditions, lighting, temperature, humidity, amount of feed, and the amount of other nutrients in the diet were equal for all treatment groups and according to specifications of the management guide for broiler production. Eggs from each replicate were collected up to six times daily for nine weeks. Every three days, eggs were transferred to a hatchery and their characteristics were determined. The results showed 5- to 15-fold Vitamin E levels over the recommended daily dose had significant negative effects on hatchability and related parameters as well as on herd economic index (P<0.05).