In this study, there was evaluation of pregnancy per AI (P/AI) as a result of the first postpartum AI following four ovulation-synchronization treatments. Treatment regimens were Ovsynch-56 (OVS, n = 875; GnRH1-7d-PGF2α-56h-GnRH2-16h-FTAI), CIDR-OVS (n = 1001; OVS plus CIDR inserts between GnRH1 and PGF2α), Double-Ovsynch (DOVS, n = 663; imposing Pre-OVS followed by breeding-OVS 7 days later), and Modified-DOVS (M-DOVS, n = 1397; imposing Pre-OVS followed either by breeding-OVS or CIDR-OVS based upon the ovarian structure at GnRH1). Cows with a corpus luteum were assigned to a breeding-OVS treatment regimen and those that did not have a corpus luteum were assigned to the CIDR-OVS treatment regimen. Compared with OVS, the P/AI of the cows in the M-DOVS (OR = 1.5, P = 0.001) and CIDR-OVS (OR = 1.4, P = 0.017) was greater at day 30. At day 70, only in the M-DOVS group was there a greater P/AI compared with the OVS group (OR = 1.7, P < 0.001). Pregnancy loss between days 30 and 70 was greater in cows of the CIDR-OVS (OR = 1.9, P = 0.014) compared with those of the OVS group. In cows of the M-DOVS, the dominant ovarian structures (follicle, corpus luteum or cyst) at different time-points of the pre-synchronization period and occurrence of estrus at the end of this period were not associated with P/AI at day 30 post-AI. In conclusion, imposing CIDR-OVS in cows that did not respond to pre-synchronization treatments, resulted in an enhanced pregnancy percentage with the use of the DOVS.

中文翻译：

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在两次Ovsynch治疗方案后，使用CIDR-Ovsynch方案治疗对预同步治疗无效的母牛，可提高总妊娠率。

在这项研究中，由于四个排卵同步治疗后首次产后AI，对每个AI（P / AI）的妊娠进行了评估。治疗方案为Ovsynch-56（OVS，n = 875;GnRH1-7d-PGF2α-56h-GnRH2-16h-FTAI），CIDR-OVS（n = 1001; OVS加上GnRH1和PGF2α之间的CIDR插入物），双Ovsynch（ DOVS，n = 663；在7天后实施Pre-OVS，然后进行育种OVS），以及Modified-DOVS（M-DOVS，n = 1397；实施Pre-OVS，然后进行育种-OVS或CIDR-OVS，基于GnRH1的卵巢结构）。将具有黄体的母牛分配给繁殖-OVS治疗方案，将没有黄体的母牛分配给CIDR-OVS治疗方案。与OVS相比，第30天，M-DOVS（OR = 1.5，P = 0.001）和CIDR-OVS（OR = 1.4，P = 0.017）的奶牛的P / AI更高。在第70天，与OVS组相比，只有M-DOVS组的P / AI更高（OR = 1.7，P <0.001）。与OVS组相比，CIDR-OVS奶牛的第30天至第70天的妊娠损失更大（OR = 1.9，P = 0.014）。在M-DOVS奶牛中，预同步期不同时间点的主要卵巢结构（卵泡，黄体或囊肿）和该期末发情的发生与每天的P / AI无关30后AI。总之，将CIDR-OVS强加于对同步前处理无反应的母牛，使用DOVS可提高妊娠率。014）与OVS组的相比。在M-DOVS奶牛中，预同步期不同时间点的主要卵巢结构（卵泡，黄体或囊肿）和该期末发情的发生与每天的P / AI无关30后AI。总之，将CIDR-OVS强加于对同步前处理无反应的母牛，使用DOVS可提高妊娠率。014）与OVS组的相比。在M-DOVS奶牛中，预同步期不同时间点的主要卵巢结构（卵泡，黄体或囊肿）和该期末发情的发生与每天的P / AI无关30后AI。总之，将CIDR-OVS强加于对同步前处理无反应的母牛，使用DOVS可提高妊娠率。