Mississippi State University
Lemley, Caleb O.
Rude, Brian J.
Date of Degree
Graduate Thesis - Open Access
Master of Science (M.S.)
College of Agriculture and Life Sciences
Department of Animal and Dairy Sciences
The objective of this study was to examine hepatic steroid inactivation and luteal function throughout bovine gestation. In pregnant beef cows, cytochrome P450 3A activity decreased from mid- to late-gestation, while progesterone concentrations tended to increase from mid- to late-gestation. Uridine diphosphate-glucuronosyltransferase activity per kg of body weight was increased in pregnant vs non-pregnant dairy cows. Total corpus luteum (CL) blood perfusion tended to be increased in pregnant vs non-pregnant dairy cows. Hepatic portal blood flow per kg of body weight was increased in pregnant vs non-pregnant dairy cows. Hepatic steroid inactivating enzyme activity, CL blood perfusion, and portal blood flow did not differ between pregnant and non-pregnant beef cows. There was no difference in progesterone concentrations in pregnant vs non-pregnant dairy or beef cows. The current study highlights the relevance of further investigation into steroid secretion and inactivation and their impact on the maintenance of pregnancy in cattle.
Hart, Caitlin G., "Examining Hepatic Steroid Inactivation and Luteal Function throughout Bovine Pregnancy" (2014). Theses and Dissertations. 2106.