Tenhagen B A, Drillich M, Heuwieser W
AG Bestandsbetreuung and Qualitätsmanagement der Tierklinik für Fortpflanzung, Fachbereich Veterinärmedizin, Freie Universität Berlin, Königsweg 63, D-14163, Germany.
J Vet Med A Physiol Pathol Clin Med. 2000 Dec;47(10):577-84. doi: 10.1046/j.1439-0442.2000.00317.x.
The effect of two insemination policies after synchronization of oestrus on reproductive performance in two groups of cows was investigated. Oestrus was synchronized by two treatments with prostaglandin F2 alpha (PGF2 alpha) at a 14-day interval. Cows in Group 1 (n = 234) were inseminated twice on appointment 66 and 90 h after the second treatment. Cows in Group 2 (n = 222) were intensively watched for signs of oestrus after the synchronization protocol and inseminated on observed oestrus. Cows with abnormal discharge after synchronization were excluded from breeding and inseminated later during the study period. Service rate within 1 week after synchronization was higher in Group 1 than in Group 2 (89.3 versus 67.1%). Conception rates on first service did not differ between groups (33.2 versus 30.0%). Days to first service and days open were shorter in Group 1 (P < 0.05). The number of cows culled for infertility did not differ between the groups. Endometritis 14-20 days post-partum decreased the percentage of cows pregnant at the end of the study period in both groups but did not have a significant effect on conception rates and days open. It is concluded that additional inseminations required in the timed artificial insemination protocol were economically justified by the reduction in days open in comparison with insemination on observed oestrus after synchronization.
研究了两组奶牛发情同步后两种授精策略对繁殖性能的影响。通过间隔14天用前列腺素F2α（PGF2α）进行两次处理来同步发情。第1组（n = 234）的奶牛在第二次处理后的66和90小时按预约进行两次授精。第2组（n = 222）的奶牛在同步方案后密切观察发情迹象，并在观察到发情时进行授精。同步后有异常分泌物的奶牛被排除在繁殖之外，并在研究期间稍后进行授精。第1组同步后1周内的输精率高于第2组（89.3%对67.1%）。两组首次输精的受胎率没有差异（33.2%对30.0%）。第1组首次输精天数和空怀天数较短（P < 0.05）。两组因不育而淘汰的奶牛数量没有差异。产后14 - 20天的子宫内膜炎降低了两组在研究期末怀孕奶牛的百分比，但对受胎率和空怀天数没有显著影响。得出的结论是，与同步后观察到发情时授精相比，定时人工授精方案中所需的额外授精因空怀天数的减少而在经济上是合理的。
