The aim of this study was to evaluate the effects of dietary supplementation of vitamin E to sows on sow fertility and serum α-tocopherol, growth and physiological state of their weanling pigs. A total of 60 Large White gilts were randomly allotted to three groups (20 gilts per group) from coitus to lactation phases over a two-parity period to evaluate the effects of dietary vitamin E on fecundity rates and litter size of sows. Each of the three dietary vitamin E treatment combinations involved 0, 40 or 70 IU/kg of dl- α-tocopheryl acetate/kg of diet, and parity 1 and 2. Sow serum α-tocopherol and Selenium (Se) were collected at 30 day post coitum, 99 day of gestation and 21 day lactation. Serum α-tocopherol and Se were collected from piglets at 1 day post natum and on day 21 (weaning age). Data relating to sow fecundity and litter size were also recorded. Results indicate that body weights and body weight gains of sows and their litters increased significantly (P < 0.01) by parity, increasing more from parities 1 to 2, mostly when dietary vitamin E was increased from 40 to 70 IU/kg diet. The highest number of total piglets and number of piglets born alive (12 ± 8.9 vs. 11 ± 0.1) were obtained at parity 2 when dietary vitamin E was increased to 70 IU/kg diet. There was an increase in weights of the piglets when dietary vitamin E was increased in sow’s diet. There was a dramatic increase in serum α-tocopherol and Se concentrations following 40 and 70 IU/kg of vitamin E supplementation during the 30 and 99 day gestation and 21 day lactation periods as parity increased. Se concentrations were about 3 fold higher in the 70 IU/kg vitamin E supplemented group in parity 2 compared to the other groups. In both parities, female piglets had higher serum α-tocopherol and Se concentrations at both 2 day post natum and on day 21 (weaning) compared to the male piglets. Results from this study suggest that supplementing 70 IU/kg α-tocopheryl acetate in sow’s diets appears to enhance growth of their weanling piglets
