This study was carried out with the objective of evaluating the effects of supplementation of two levels of crude protein (14 and 16% CP) and vitamin E (25 and 250mg VE/kg) in the diet on the performance and egg composition of broiler breed hens and on the performance of their progeny during the laying period (24-to-54 weeks of age). Thus 480 female and 48 male Ross breeder 18-week-old birds were randomly distributed in 16 floor pens, with 30 females and three males in each one. The diets were based on corn and soybean meal, and all them were isoenergetics (2750kcal ME/kg). The experimental design was a complete randomized block and the treatments were arranged in 2 × 2 factorial (CP × VE levels) with two repetitions each. Egg production/hen/day, egg weight, egg number/hen housed, viability, final female body weight and egg yolk percentage were not affected (P>0.05) by the treatments, and no interaction between CP and VE was observed. Hens fed diet with 16% CP, supplemented with 25 or 250mg VE/kg, had smaller egg shell and greater albumen percentage (P<0.05). Diet with 250mg VE/kg resulted in greater alpha tocopherol concentration in the yolk (P<0.05). No effects of CP or VE levels were observed on incubation performance in both studied ages (32nd and 52nd week), i.e., on incubated egg weight, on eclodibility, on relationship between egg weight and neonatal chick weight, and on subsequent performance of the progeny. However, greater neonatal chick weight (P<0.01) was observed in those from 32 week-old broiler breed hens fed diet containing 16% CP and 250mg VE/kg. It can be concluded that a 14% CP with 25mg VE/kg diet provides sufficient CP and VE to assure the productive and reproductive performance of broiler breeder hens during the laying period.
Broiler breed hen; protein; vitamin E; egg production; egg composition
