Cooperative Department of Veterinary Medicine, Faculty of Agriculture, Iwate University, Morioka City, Iwate, Japan.
Anim Sci J. 2020 Jan-Dec;91(1):e13477. doi: 10.1111/asj.13477.
For the timed re-insemination at the minimal interbreeding interval, cows were treated with a progesterone (P )-releasing intravaginal device from Days 13-15 to 21 post-insemination (Day 0 = estrus), followed by plasma P assay on Day 23 and then subjected to the Experiments 1 and 2. In Experiment 1, of 18 cows, 6 cows were determined as luteolysis with low (<1 ng/ml) plasma P concentrations on Day 23 and ovulated on Days 24 (3 cows), 25 (1 cow), and 26 (1 cow) except a cow affected by ovarian quiescence. In Experiment 2, all cows were treated with GnRH on Day 23. Cows with low (<1 ng/ml) plasma P concentrations on Day 23 were diagnosed as non-pregnant and subjected to the re-insemination in the morning of Day 24 irrespective of estrous signs. Of 36 cows, 15 cows were diagnosed as being non-pregnant on Day 23. Fourteen cows of the non-pregnant animals were re-inseminated in the morning of Day 24 irrespective of estrous signs and the pregnancy rate of re-insemination was 36%. The conception rates of initial and re-inseminations were 50% (18/36) and 36% (5/14), respectively. The overall pregnancy rate by adding the rates of initial and re-inseminations was 64% (23/36).
对于定时复配，在输精后 13-15 天至 21 天（第 0 天=发情），使用孕酮（P）释放阴道装置处理母牛，然后在第 23 天进行血浆 P 检测，然后进行实验 1 和 2。在实验 1 中，18 头母牛中有 6 头被确定为黄体溶解，第 23 天血浆 P 浓度低（<1ng/ml），并在第 24 天（3 头）、第 25 天（1 头）和第 26 天（1 头）排卵，除了一头受卵巢静止影响的牛。在实验 2 中，所有母牛在第 23 天接受 GnRH 处理。第 23 天血浆 P 浓度低（<1ng/ml）的母牛被诊断为未怀孕，并在第 24 天上午进行复配，无论发情迹象如何。在 36 头母牛中，有 15 头在第 23 天被诊断为未怀孕。在第 24 天上午，不考虑发情迹象，对 14 头未怀孕的动物进行复配，复配的妊娠率为 36%。初配和复配的妊娠率分别为 50%（18/36）和 36%（5/14）。将初配和复配的妊娠率相加，总妊娠率为 64%（23/36）。
