腾冲马同期发情和定时输精技术研究

Synchronization of Oestrus and Timed Insemination of Tengchong Mares

本实验旨在探究孕酮缓释硅胶栓结合氯前列醇钠和促性腺激素释放激素(GnRH)类似物处理对母马同期发情和定时输精效果的影响。在繁殖季节,选取43头不同胎次的健康空怀腾冲母马,分为A、B组。A组(n=23)中第1、2、3胎次母马数量分别为6、10、7头,均肌注1 mL GnRH类似物记作第0天,第2天阴道内埋植阴道孕酮缓释硅胶栓,第8天肌肉注射4 mL氯前列醇钠,第11天取栓的同时再次肌肉注射4 mL氯前列醇钠,第12~16天B超检查卵泡发育状态。当卵泡直径到33 mm时,注射GnRH类似物1 mL,8 h后用低温保存的公马精液进行输精,输精后24 h和48 h检查母马排卵率,配种后15 d检查受胎率。B组(n=20)均为第2胎次,不做任何激素处理,在自然发情条件下进行B超检测和人工授精处理,记录其发情、排卵和受胎率。结果表明:A组在处理的第12~16天,86.95%的母马卵巢出现直径大于33mm的卵泡,一次输精后的情期受胎率为65.00%;B组在12~16 d内,20.00%的母马卵巢出现直径大于33mm的卵泡,情期受胎率为75.00%。本实验方案对前3胎次母马的发情同步率和怀孕率没有显著差异。因此,本实验处理方案可以使母马群在配种季节集中发情和配种,大大减少卵泡发育的检查时间和配种次数,并能获得较理想的受胎率。

This study was aimed to research the effect of intravaginal application of progesterone-releasing device(PRID) with Cloprostenol Sodium(PG) and GnRH analogue to estrus synchronization and timed insemination of mares. During breeding season, a total of 43 healthy and non-pregnant mares were divided into group A and group B. In group A, the numbers of mares which had born one, two and three foals were 6, 10 and 7, respectively. All of them were intramuscularly injected 1 mL GnRH analogue on d 0. On d 2, a PRID was administered intravaginally for 9 days, and 4 mL PG was intramuscularly injected on d 8. On d 11, the PRID was took off and 4 mL PG was intramuscularly injected at the same time. Then, estrus status was examined by ultrosound between d 12 and d 16. When follicles developed to 33 mm, a total of 1 mL GnRH analogue was intramuscularly injected, and cooling semen was inseminated 8 h later. The ovulation rate was checked after injection 24 h and 48 h, and pregnancy rate was detected after ovulation 15 days. All mares had born two foals in group B as control. The results indicated that, there were 86.95% mares appeared 33 mm follicles between d 12 and d 16, and the pregnancy rate was 65.00% after insemination in group A. The appearance rate of 33 mm follicles was 20.00% between d 12 and d 16, and the pregnancy rate was 75.00% in group B. In conclusion, there was no difference in estrus synchronization and pregnancy rate between mares which had one, two and three foals(P>0.05). Thus, this estrus synchronization allow mares to concentrate on estrus and insemination during 5 days without affecting the conception rate, which make the breeding work more convenient by reducing palpation and insemination times.