EN
The aim of the present study was the description of the dynamics in erythrocyte GSH-Px activity and serum selenium content changes in sows during 14 days before and 14 days after parturition. The experiment was performed on 36 gilts of 1-3 years old. All animals came from the same farm with a closed production system and were fed the same diet of unknown selenium content. Blood was collected 8 times: 13-14 days before parturition, 6-7 days before parturition, 48-72 hours before parturition, and 12-24 hours before parturition, as well as 12-24 hours after parturition, 48-72 hours after parturition, 6-7 days after parturition and 13-14 days after parturition, always after feeding. Blood was centrifuged to obtain serum and erythrocytes were hemolysed. Erythrocyte GSH-Px activity was determined by the Paglia and Valentine method and expressed in U per g Hb. Serum selenium content was determined by the atomic absorption method. GSH-Px activity 14 days before parturition reached 13.38 U/g Hb and significantly decreased around the 7th day before parturition to 11.26 U/g Hb. 72 hours before parturition the activity of the enzyme increased to 16.85 U/g Hb. Between the 72nd hour before and the 14lh day after parturition GSH-Px activity remained constant. Serum selenium content did not differ significantly in the examined gilts and ranged between 88.9 ug/L and 121.87 ug/L. 24 hours before and 24 hours after parturition the selenium content reached 96.55 ug/L and 88.91 ug/L respectively.