Enzyme activities in placental tissues from cows with and without retained fetal membranes.

The aim of this study was the determination and the comparison of activities of AST, ALT, GGT, 5'-NU and CK in the placental tissues of cows with and without retained fetal membranes. Placental samples were obtained from 16 cows immediately after parturition and divided into 2 groups: A-not retained (n = 10, NRF), B-retained (n = 6, RF). The activities of the examined enzymes were determined in supernatants of homogenized tissues using spectrophotometric methods and ready kits. The activity of AST was statistically significantly lower in the maternal part of the placenta in group B than in group A. There were no differences in ALT activity. The activity of GGT was statistically significantly higher in the maternal part of the placenta in group B than in group A. The activity of 5'-NU was statistically significantly higher in the maternal part than in the fetal part of placenta in both groups examined. The activity of CK did not differ, except for statistically significant lower activity in the fetal part of the placenta in group B. The results can suggest that the metabolism of amino acids is altered to some extend in cases of the retained placenta. Changes in GGT my indicate on imbalance in free radicals generation and neutralisation. Energetic status may not be influenced by the retention of the fetal membranes. Further experiments concerning more frequent sample collecting during whole periparturient period are necessary.