Effects of alpha-tocopherol and selenium on pregnant sows and their piglets' immunity and performance.

Four groups of 12 pregnant sows of the same genetic background, with similar litter size, living under the same housing conditions and having the same hygienic and nutritional standards, were used. In control animals (gC), a basic feed was provided, in which the dietary level of alpha-tocopherol was 20 mg/kg of feed and that of selenium (Se) was 0.45 mg/kg of feed (standard ration). Sows in the second group (gE) received basic feed supplemented with 30 mg alpha-tocopherol per kg (50 mg/kg of feed, in total). To those in the third group (gSe) basic feed was provided but additionally they were injected with 30 mg Se (sodium selenite) on days 30, 60 and 90 of pregnancy. For the sows in the fourth group (gESe), basic feed was supplemented with 30 mg alpha-tocopherol per kg. In addition they received 30 mg injectable Se (sodium selenite) on days 30, 60 and 90 of pregnancy. The experiment started on day 30 of pregnancy and lasted until weaning day (28 days post-farrowing). It was found that alpha-tocopherol and selenium act synergistically. Piglets born from sows in gESe had the highest immunoglobulin concentration level up to weaning day. All productive and clinical parameters (number of piglets born/litter, number of weaned piglets/litter, and piglets' average body weight at birth and on weaning day) were greater in these piglets in comparison with the animals of the other groups. Diarrhoea problems were minimal in the piglets in gESe.