Performance of pureline broiler breeders fed two levels of vitamin E

• Published in: Poultry science 2001-09, Vol.80 (9), p.1258-1262
• Main Authors: Siegel, P B, Price, S E, Meldrum, B, Picard, M, Geraert, P A
• Format: Article
• Language: English
• Subjects: Age Factors; Agricultural sciences; Animal production studies; Animals; Antioxidants - analysis; Antioxidants - pharmacology; Behavior, Animal - drug effects; Body Weight; Chickens - blood; Chickens - genetics; Chickens - physiology; Dose-Response Relationship, Drug; Egg Yolk - chemistry; Eggs - analysis; Female; Life Sciences; Oviposition - drug effects; Time Factors; Vitamin E - administration & dosage; Vitamin E - analysis; Vitamin E - blood; Vitamin E - pharmacology
• ISSN: 0032-5791
• DOI: 10.1093/ps/80.9.1258

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 production 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 production differed between diets (300 > 10 IU/kg). These differences between diets were consistent with the greater number 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 amount of feed, BW gains were greater for Line B than A and for the 300- than the 10-IU/kg level of vitamin E. Heterophil (H):lymphocyte (L) ratios, percentage livability, and relative asymmetries of shank length and diameter were similar among groups. Pullets from Line B and those fed the higher level of vitamin E exhibited more fear than their counterparts. Head shaking did not differ between vitamin E levels; however, there was a line-by-time of day interaction for this behavior. The 30-fold difference in dietary vitamin E was reflected by a 15-fold difference in plasma vitamin E levels in both lines. For vitamin E level in the yolk, however, there was a line-by-diet interaction. The interaction resulted from no difference between lines at the 10 IU/kg level and differences of 10- and 6+-fold in Lines B and A at the 300 IU/ kg level, respectively. Overall, responses to continuous feeding of vitamin E at these levels were influenced by genetic stock, age, duration of feeding, and measurement criteria.