Dipartimento di Scienze Veterinarie, Università di Pisa, Pisa, Italy.
Reprod Domest Anim. 2024 Apr;59(4):e14555. doi: 10.1111/rda.14555.
Most of the northern hemisphere donkey breeds are faced with the risk of extinction, thus donkey reproduction is considered an emerging branch of theriogenology, and the management of artificial insemination and induction of ovulation is a crucial point in setting up preservation protocols. For four consecutive cycles, six jennies' ovarian activity was routinely monitored; an ultrasound examination was performed daily from the evidence of a follicle diameter ≥27 mm until ovulation. Upon reaching a follicular diameter ≥32 ± 2 mm (Hour 0), oestrous jennies were treated alternatively with 0.1 mg triptorelin acetate, sc, (TRIP), 0.4 mg/sc of buserelin acetate (BUS) or saline, sc, (CTRL) and examined ultrasonographically at Hours 14, 24, 38, 42, 48, 62 and every 24 h until ovulation. Induction of ovulation was considered successful if ovulation occurred from 24 to 48 h after treatment. 11/12 cycles resulted in ovulation for TRIP and 12/12 for BUS and CTRL groups, respectively. Mean ± SD ovulation time after treatment was 37.3 ± 8.3, 47.1 ± 21.0 and 66.8 ± 25.9 h for BUS, TRIP and CTRL, respectively (p = .0032). Ovulation rates between h24 and h48 were 10/12 (83.3%) for both TRIP/BUS and 2/12 (16.7%) for CTRL, respectively (p = .003). Buserelin and triptorelin-treated jennies had a 25 times higher probability to ovulate between Hours 24 and 48 than controls (p = .003), while there were no jenny and cycle effects on the ovulatory rate. The results of this study show how triptorelin successfully induced ovulation in jennies, like other GnRH analogues previously evaluated.
大多数北半球的驴品种都面临灭绝的风险，因此驴的繁殖被认为是动物繁殖学的一个新兴分支，而人工授精和排卵诱导的管理是建立保护协议的关键点。在连续四个周期中，常规监测了六头母驴的卵巢活动；从卵泡直径≥27mm 的证据开始，每天进行一次超声检查，直到排卵。当卵泡直径达到≥32±2mm（0 小时）时，发情母驴交替接受 0.1mg 醋酸曲普瑞林（TRIP）、0.4mg/sc 醋酸布舍瑞林（BUS）或生理盐水（CTRL）治疗，并在 14、24、38、42、48、62 小时和排卵后每隔 24 小时进行超声检查。如果在治疗后 24 至 48 小时内发生排卵，则认为排卵诱导成功。TRIP 组的 11/12 个周期和 BUS 和 CTRL 组的 12/12 个周期均成功排卵。治疗后排卵时间的平均值±SD 分别为 BUS、TRIP 和 CTRL 组的 37.3±8.3、47.1±21.0 和 66.8±25.9h（p=0.0032）。TRIP/BUS 组的 24 至 48 小时之间的排卵率为 10/12（83.3%），而 CTRL 组为 2/12（16.7%）（p=0.003）。与对照组相比，促黄体生成素释放激素类似物（GnRH）处理的母驴在 24 至 48 小时之间排卵的可能性高 25 倍（p=0.003），而母驴和周期对排卵率没有影响。本研究结果表明，与以前评估的其他 GnRH 类似物一样，曲普瑞林成功地诱导了母驴排卵。
