Author : Joseph Andrew Binversie
Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (756 download)
Book Synopsis Modifying the Double-ovsynch Protocol to Include Human Chorionic Gonadotropin to Synchronize Estrus in Dairy Cattle by : Joseph Andrew Binversie
Download or read book Modifying the Double-ovsynch Protocol to Include Human Chorionic Gonadotropin to Synchronize Estrus in Dairy Cattle written by Joseph Andrew Binversie and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The objectives of this study were to determine whether conception, ovulation rates, presynchronization rates, or follicle and CL characteristics were altered after modifying the Double-Ovsynch (DO) protocol to include human chorionic gonadotropin (hCG) compared to the conventional DO protocol in dairy heifers and lactating dairy cows. We hypothesized that replacing the first injection of gonadotropin releasing hormone (GnRH) in the DO protocol with hCG would increase the proportion of females that ovulate, thus improving the presynchronization rate leading to increased conception rates. Ovulation rates were increased in cows administered hCG compared to GnRH, but subsequent synchronization, and conception rates did not differ between treatments. A greater proportion of hCG-treated cows tended to fail to have undergone luteolysis compared to those treated with GnRH. In conclusion, no improvement in overall fertility was achieved by replacing the first injection of GnRH in the DO protocol with hCG.