Authors : A. Dehghan , M. Emady and M. Aminlari
Abstract: In this study Collagenase-Like Enzyme Specific (CLES) activity was measured in placentomes of cows with or without Retained Fetal Membranes (RFM) and its correlation with steroid hormones was also evaluated. Preparum dairy cows (n = 12) were randomly assigned to two groups. The control cows (n = 7) were calved spontaneously and released their fetal membranes within 12 h of calving and served as the Non-RFM group. Treatment cows (n = 5) received dexamethasone for induction of calving. All treated cows did not release their fetal membranes within 12 h after calving and served as the RFM group. In the Non-RFM group, blood samples were collected 2-3 days before calving and every 12 h thereafter until calving. In the RFM group, blood samples were collected immediately before dexamethasone injection and every 12 h thereafter until calving. In both groups two other samples were collected at around calving and 12 h after calving. Tissue samples were taken from placentomes of both groups, around 12 h after calving and CLES activity was determined. The results did not show any significant difference in CLES activity between the 2 groups. Serum estradiol-17 (E2) concentration was not statistically different between the 2 groups but its changes over time between groups was found to be significantly different. A significant difference between the groups in Estradiol/Progesterone (E2/P4) ratios was also observed. The results of our study indicate that prepartum estrogens concentrations can influence collagenase activity in placentomes and may have an important role in maturation and release of fetal membranes.
A. Dehghan , M. Emady and M. Aminlari , 2007. Relationship Between Collagenase-Like Specific Activities in Placentome and the Level of Steroid Hormones in Retained and Non-Retained Fetal Membrane Cows . Journal of Animal and Veterinary Advances, 6: 745-751.