Performance of Pureline Broiler Breeders Fed Two Levels of Vitamin E

ABSTRACT Reported in this paper is an experiment designed to evaluate responses of two commercial broiler dam purelines (A and B) continuously fed 10 or 300 IU of vitamin E/kg from 168 to 441 d of age. Prior to Day 168, all pullets were fed diets containing 10 IU of vitamin E/kg. During the early laying period, percentage hen-day ovulations and percentage hen-day normal egg pro-duction were similar for both lines and diets. During the latter part of the laying cycle, there were differences between lines for these traits (A> B), as well as for BW and egg weight for which line differences were reversed (A < B). Also during this period, percentage hen-day ovulations and percentage hen-day normal egg produc-tion differed between diets (300> 10 IU/kg). These differ-ences between diets were consistent with the greater num-ber of females that entered lay and higher hen-housed egg production of the 300- than 10-IU/kg group. Although during the laying cycle all females received a fixed (Key words: broiler pureline, vitamin E, egg production, relative asymmetry, body weight