Hanwoo Experiment Station, National Institute of Animal Science, Rural Development Administration, Pyeongchang, Gangwon-Do, South Korea.
Theriogenology. 2013 Nov;80(8):855-61. doi: 10.1016/j.theriogenology.2013.07.010. Epub 2013 Aug 9.
Ineffective estrus detection is the foremost limiting factor in the fertility of farmed cattle worldwide. Failure to detect estrus or erroneous diagnosis of estrus results in great economic losses in Korea each year. This study was carried out in order to comprehensively describe the estrus behaviors and conception rates of different estrus synchronization protocols applied to 40 cycling native Korean cattle (Hanwoo). The cows were grouped into four (n = 10) and treated with the following protocols: (1) Day -15: controlled intravaginal drug-releasing device (CIDR) for 12 days; Day -5: prostaglandin F2α (PGF2α), (2) ovulation synchronization (OVS): Day -15: GnRH; Day -6: PGF2α; Day -4: GnRH, (3) Day -15: progesterone-releasing intravaginal device for 12 days; Day -5: PGF2α; and (4) Day -15: PGF2α; Day -4: PGF2α. Artificial insemination was performed 12 hours after the detection of estrus using frozen-thawed semen. Estrus signs were compared using a charge-coupled device camera (CCDC) and a control method (direct visual observation). The pregnancy of the cows was determined by transrectal ultrasonography at Days 25 to 30 postinsemination. The results indicated that the day of estrus return was significantly earlier using the CCDC method compared with direct visualization (P < 0.05). Mounting of other cows was the most predominant sign of estrus among the flock (P < 0.05), as analyzed using the CCDC. In the OVS group, a lower rate of mounting was observed than in the other three groups. Moreover, significantly fewer estrus behaviors were noticed in the OVS protocol group (P < 0.05). Both first service conception and overall conception rates were significantly higher (P < 0.05) in the CIDR and OVS treatment groups. In conclusion, the CIDR and OVS protocols appear to be the best practice for the synchronization of estrus for reproductive competence through the CCDC in Hanwoo cows. However, CIDR has a practical advantage over OVS with respect to estrus detection.
乏情检测是全球养殖牛群繁殖力的首要限制因素。在韩国，每年因未能检测到发情或发情诊断错误而导致巨大的经济损失。本研究旨在全面描述不同发情同步方案在 40 头循环的本地韩国牛（韩牛）中的发情行为和受孕率。将牛分为四组（n = 10），并分别用以下方案处理：（1）-15 天：持续 12 天的阴道内控释装置（CIDR）；-5 天：前列腺素 F2α（PGF2α），（2）排卵同步（OVS）：-15 天：GnRH；-6 天：PGF2α；-4 天：GnRH，（3）-15 天：持续 12 天的阴道内孕酮释放装置；-5 天：PGF2α；（4）-15 天：PGF2α；-4 天：PGF2α。发情检测后 12 小时，使用冻融精液进行人工授精。发情迹象通过电荷耦合器件摄像机（CCDC）和对照方法（直接视觉观察）进行比较。牛的妊娠通过直肠超声在授精后 25 至 30 天确定。结果表明，与直接可视化相比，使用 CCDC 法发情返回的天数明显更早（P < 0.05）。在羊群中，其他牛的交配是最主要的发情迹象（P < 0.05），这是通过 CCDC 分析得出的。在 OVS 组中，观察到的交配率低于其他三组。此外，在 OVS 方案组中，发情行为明显减少（P < 0.05）。CIDR 和 OVS 治疗组的首次配种受孕率和总受孕率均显著提高（P < 0.05）。总之，CIDR 和 OVS 方案似乎是通过 CCDC 实现韩牛发情同步的最佳实践，从而提高繁殖能力。然而，CIDR 在发情检测方面比 OVS 具有实际优势。
