EN
The aim of the study was to determine plasma levels of vitamin C and reduced glutathione (GSH) in sows between the day 14 prepartum and day 14 postpartum. The study involved twenty-four sows of three breeds - Polish Large White (PLW), Polish Landrace (PL) and PLWxPL aged 1-3 years. All the animals were from one closed-cycle production farm. The mean vitamin C level on days 13-14 prepartum reached 0.49 ±0.19 mmol/g of protein and decreased significantly (P<05) at 24-48 h postpartum to 0.33 ±0.19 mmol/g of protein. On days 6-7 and 13-14 postpartum, the vitamin C level further decreased to 0.17 ±0.006 and 0.15 ±0.007 mmol/g of protein, respectively. The mean GSH level on days 13-14 before delivery was 0.071 ±0.009 mmol/g of protein and decreased significantly (P0.05) at 24-48 h before delivery to 0.062 ±0.018 mmol/g of protein. In this period, the mean GSH level was similar to that observed during the first 24-48 h postpartum. On day 6-7 after delivery, the level of GSH reached the values observed on days 13-14 and 6-7 prepartum. On days 13-14 postpartum, the level of GSH was found to be 0.115 ±0.029 mmol/g of protein and was significantly higher (P<0.001) compared to that on days 13-14 prepartum. The findings suggest that porcine levels of vitamin C and glutathione decrease during the periparturient period, which may lead to a decreased antioxidant defence system and an imbalance in redox homeostasis.