Department of Obstetrics Gynaecology and Reproduction, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, Thailand.
Theriogenology. 2010 Nov;74(8):1371-6. doi: 10.1016/j.theriogenology.2010.06.007. Epub 2010 Aug 12.
This study evaluated fertility in swamp buffalo after synchronization of ovulation combined with fixed time artificial insemination. At the start of the study, designated day 0, from a group of 98 female Thai swamp buffalo, 55 buffalo (heifers n° = 20 and cows n° = 35) were selected to be synchronized with GnRH (Day 0) followed by PGF₂alpha (Day 7) and a second treatment with GnRH (Day 9). All buffalo were inseminated at two fixed times 12 h and 24 h after the second injection of GnRH (Ovsynch+TAI group); a second group of 43 buffalo (heifers n° = 19 and cows n° = 24) were not treated and were artificially inseminated (AI) at natural estrus (AI group). Blood samples were taken 22 days after insemination to evaluate progesterone plasma levels. In the Ovsynch+TAI group, overall conception rate (CR; i.e. the number of cows with progesterone >4.0 ng/ml on day 22 after AI divided by the number of animals inseminated), was 38.1% and overall pregnancy rate (PR; i.e. the number of cows that were pregnant at day 50-60 after insemination divided by the number of animals inseminated), was 32.7%. In the AI group overall CR and PR was 34.9%. Within the Ovsynch+TAI group, CR and PR were reduced (P < 0.05) in heifers compared with cows (CR 15.0% vs. 51.4% for heifers and cows, respectively; PR 15.0% vs. 42.9% for heifers and cows, respectively). Within the AI group the efficacy of treatment was similar between heifers and cows (CR and PR 31.6% for heifers and 37.5% for cows). In conclusion, this study indicates that in swamp buffalo it is possible to synchronize ovulation and use timed artificial insemination with the Ovsynch+TAI protocol.
本研究评估了排卵同步结合定时人工授精对沼泽型水牛的繁殖力的影响。在研究开始时，从一群 98 头泰国沼泽型水牛中，选择了 55 头水牛（小母牛 n° = 20，母牛 n° = 35）进行 GnRH 同步（第 0 天），然后使用 PGF₂alpha（第 7 天）和第二次 GnRH 处理（第 9 天）。所有水牛在第二次 GnRH 注射后 12 小时和 24 小时进行两次定时人工授精（Ovsynch+TAI 组）；第二组 43 头水牛（小母牛 n° = 19，母牛 n° = 24）未进行处理，在自然发情时进行人工授精（AI 组）。在授精后 22 天采集血样，以评估孕酮的血浆水平。在 Ovsynch+TAI 组中，总受胎率（CR；即授精后 22 天孕酮>4.0ng/ml 的母牛数除以授精动物数）为 38.1%，总妊娠率（PR；即授精后 50-60 天怀孕的母牛数除以授精动物数）为 32.7%。在 AI 组中，总 CR 和 PR 为 34.9%。在 Ovsynch+TAI 组中，小母牛的 CR 和 PR 低于母牛（CR 分别为 15.0%和 51.4%；PR 分别为 15.0%和 42.9%）。在 AI 组中，小母牛和母牛之间的治疗效果相似（CR 和 PR 分别为 31.6%和 37.5%）。综上所述，本研究表明，在沼泽型水牛中，使用 Ovsynch+TAI 方案同步排卵并进行定时人工授精是可行的。
