Influence of Increased Dietary Selenium on Glutathione Peroxidase Activity and Glutathione Concentration in Erythrocytes of Lactating Sows

We studied the influence of different selenium (Se) levels on some parameters of the antioxidant potential of lactating sows. The experiment involved 15 sows of the Large White breed divided into 3 equal groups. The addition of Se (from Se-enriched yeast) amounted to 0.0, 0.25 and 0.50 mg per kg of diet in the control, Se1 and Se2 groups, respectively. Erythrocyte Se concentration, glutathione peroxidase (GPx) activity and reduced/oxygenated glutathione ratio were measured as some of the indicators of the sow’s antioxidant status. Supplementation of Se at 0.25 mg/kg of diet increased Se concentration (by 50.0%; P<0.01), GPx activity (by 17.0%: P<0.05) and reduced/ oxygenated glutathione ratio (by 29.7%; P<0.05). Addition of Se at 0.50 mg/kg of diet increased Se concentration (by 63.6%; P<0.01), GPx activity (by 34.7%; P<0.01) and reduced/oxygenated glutathione ratio (by 64.0%; P<0.01). A significant relationship (P<0.01) was found between the Se concentrations and activity of GPx in erythrocytes from sows in the Se1 and Se2 groups (r=0.76 and 0.77, respectively). Percentage of piglets weaned/born was higher (P>0.05) in the Se2 than in the Se1 and control groups. In summary, addition of 0.25 or 0.50 mg Se/kg of diet can improve antioxidant status of lactating sows, but addition of 0.25 mg Se/kg may be also sufficient.