Supplemental Vitamin E: a requirement for optimizing fecundity rates and litter size in sows

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 per kg of dl-alpha-tocopheryl acetate per kg of diet, and parity 1 and 2. Sow serum alpha-tocopherol and Selenium (Se) were collected on the 30th d post coitum, 99th d of gestation and 21st d of lactation. Serum alpha-tocopherol and Se were collected from piglets at 1 d post birth and 21 d weaning age. Data relating to sow fecundity and litter size were also recorded. Results indicated that body weights and body weight gains of sows and their litters increased significantly (P less than 0.01) by parity, increasing more from parities 1 to 2, mostly when dietary vitamin E was increased from 40-70 IU per kg diet. The highest total piglets and number of piglets born alive (12 + or - 8.9 v. 11 + or - 0.1) were obtained at parity 2 when dietary vitamin E was increased to 70 IU per kg diet. There was an increase in weights of the piglets when dietary vitamin E was increased in the sow's diet. There was a dramatic increase in serum alpha-tocopherol following 40 and 70 IU per kg of vitamin E supplementation during the 30th and 99th d gestation and 21st d lactation periods as parity increased. Se concentrations were about three-fold lower in 70 IU per kg of the vitamin E supplemented group in parity 2 compared with the respective groups. In both parities, female piglets gave higher serum alpha-tocopherol and Se at both 2 d post birth and 21 d weaning periods compared with the male piglets. Based on the results, supplementation 70 IU per kg alpha-tocopheryl acetate in sows diets appears to be most beneficial in optimizing fecundity rates in sows and the survival of their litters.