Selenium and vitamin E in sow diets: I. Effect on antioxidant status and reproductive performance in multiparous sows

This study aimed to evaluate the effects of 2 dietary selenium (Se) sources and 2 vitamin E levels during gestation and lactation on antioxidant status and reproductive performance in multiparous sows. The study was conducted in a 2×2 factorial arrangement with sodium selenite or Se-enriched yeast at 0.30mg Se/kg diet each as the Se sources and vitamin E at 30 or 90 IU/kg. A total of 234 multiparous sows were bred and started on 1 of 4 dietary treatment according to parity and body condition, and then maintained on feed until 21-d postpartum. Serum samples were collected from 6 sows per treatment at d 30, 60 and 90 of gestation (G30, G60 and G90) and d 11 of lactation (L11) for the analysis of Se level and antioxidant status, i.e., total antioxidant capacity (T-AOC), the activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), glutathione (GSH) content and malondialdehyde (MDA) content. Colostrum and 11-d milk were collected for the analysis of Se, antioxidant status and milk composition. Sows fed organic Se produced more live pigs (P<0.10), had greater litter birth weight (P<0.05) and weaned more pigs (P<0.10) compared to sows fed inorganic Se. Serum T-AOC (G60 and L11), SOD activity (G60 and G90), GSH-Px activity (L11), GSH content (L11) and Se level (G30, G60, G90 and L11) increased, and MDA content (G30, G60, G90 and L11) decreased when sows were fed organic Se (P<0.05). The activities of T-AOC (11-d milk), SOD (colostrum), GSH-Px (colostrum and 11-d milk), GSH content(11-d milk), and Se level (colostrum) were greater and MDA content (11-d milk) was lower when sows were fed organic Se (P<0.05). Total solids, solids-not-fat, protein, and lactose levels were greater in 11-d milk (P<0.05), but similar in colostrum, when sows were fed organic Se. The α-tocopherol level in serum at 30 d (P<0.05), 60 d (P<0.10), 90 d of gestation (P<0.10) and 11 d of lactation (P<0.10) and colostrum (P<0.05) and milk (P<0.05) were increased when sows were fed elevated vitamin E diets. No vitamin E level treatment or Se source×vitamin E level interaction was evident for reproductive performance and the indices measured in serum and milk (P>0.05). In conclusion, sow fed organic Se had improved the antioxidant capacity in serum and milk, the milk composition, and the number of pigs weaned compared with sow fed inorganic Se. However, antioxidant status and reproductive performance were not improved when vitamin E was added at 90 vs. 30 IU/kg, and no Se source×vitamin E level interaction was detected. Organic Se or elevated vitamin E in sows diet did not affect major parameter of sow reproduction.