Department of Clinical Veterinary Sciences, Faculty of Veterinary Medicine, University of Helsinki, Paroninkuja 20, 04920 Saarentaus, Finland.
Acta Vet Scand. 2009 Nov 30;51(1):48. doi: 10.1186/1751-0147-51-48.
The study was designed to test the effect of fixed-time artificial insemination (fixed-AI) after the slightly modified Ovsynch protocol on the pregnancy rate in beef cattle in Finnish field conditions. The modification was aimed to optimize the number of offsprings per AI dose.
Ninety Charolais cows and heifers were entered into the program an average of 1.8 times. Thus, 164 animal cases were included. Animals were administered 10-12 microg of buserelin. Seven days later animals without a corpus luteum (CL) were rejected (20.7%) while the remaining 130 cases with a CL were administered prostaglandin F2alpha, followed 48 h later with a second injection of buserelin (8-10 microg). Fixed-AI was performed 16-20 hours after the last injection.
The pregnancy rate was 51.5% (67/130). The pregnancy rate after a short interval (50-70 d) from calving to entering the program was significantly higher than that after a long interval (>70 d).
This protocol seems to give acceptable pregnancy results in beef herds and its effect on saving labour is notable.
本研究旨在测试改良后的 Ovsynch 方案后固定时间人工授精（fixed-AI）对芬兰田间条件下肉牛妊娠率的影响。该改良旨在优化每剂人工授精的后代数量。
90 头夏洛来牛和小母牛平均进入该计划 1.8 次。因此，共纳入 164 个动物病例。动物接受了 10-12μg 的布舍瑞林。7 天后，未发现黄体（CL）的动物被淘汰（20.7%），而剩余 130 个有 CL 的动物接受了前列腺素 F2α，48 小时后再次注射布舍瑞林（8-10μg）。最后一次注射后 16-20 小时进行固定-AI。
妊娠率为 51.5%（67/130）。产后至进入计划的短间隔（50-70d）的妊娠率明显高于长间隔（>70d）。
该方案似乎在肉牛群中获得了可接受的妊娠结果，其在节省劳动力方面的效果显著。
