EN
The aim of study was to investigate pre-partum and postpartum changes in the total anti-oxidant capacity (TAC), total peroxide (TPX) and oxidative stress index (OSI) of cows with dystocia compared with healthy animals. The possible relationships between these markers and relevant blood parameters were also investigated. Examinations were performed in a herd of 200 Holstein cows, aged 3-6 years. Blood samples were taken both during the 7th month of pregnancy and within the first 15 minutes postpartum. After calving, the cows were divided into two groups according to the type of birth: Group 1 dystocia (n=16) and (Group 2) normal partum (n=21). Additionally, cows in the dystocia group were divided into three subgroups, according to the reason for the dystocia: absolute birth weight (the high birth weight of calf), twin pregnancy and presentation. The results indicated that there were no changes in oxidative stress either in dystocia or during normal parturition eutoci. Oxidative stress may be decreased using an antioxidant supplement during the pre-partum period. The study also showed that oxidative stress does not affect dystocia. It may also be concluded that additional antioxidant supplementation may be required in absolute birth weight and twin pregnancy to reduce TPX levels. Analyses of urea, uric acid, and creatinine, as well as the enzyme activities of lactate dehydrogenase, alanine and aspartate transferase pre-partum do not appear to be useful for predicting dystocia. However, decreasing serum total protein may be a parameter to be used in diagnosing pathological conditions in pregnancy - particularly during late pregnancy.