Cevik M, Yilmazer C, Kocyigit A
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Pol J Vet Sci. 2017 Sep 26;20(3):501-506. doi: 10.1515/pjvs-2017-0060.
This study examined the effect of melatonin implantation during the non-breeding season on the reproductive performance of ewes and the testicular dimensions of rams. In seasonally anestrus Kivircik and Charollais ewes and rams were subjected to melatonin. Estrus response was significantly higher in treated than control ewes of both breeds (p<0.001). The pregnancy rate was significantly lower (p<0.001) in the control than in the treated animals. The twinning rate was significantly lower in melatonin implanted Kivircik than Charollais ewes (p<0.05). The testicular dimensions after 42 days of melatonin treatment increased in both breeds. Scrotal length (SL) increased in Kivircik and Charollais rams (p<0.01). The increase in scrotal circumference (SC) was more marked in the Charollais (P<0.01) than in the Kivircik rams. There was a large increase in testicular volume (TV) in both Kivircik (p<0.01) and Charollais (p<0.001) rams. This study shows that melatonin implants can be applied to induce estrus in ewes approximately four months earlier than breeding season. Melatonin implantation in the non-breeding season significantly increased testicular dimensions in Kivircik and Charollais rams thus increasing their reproductive potential.
本研究考察了在非繁殖季节植入褪黑素对母羊繁殖性能和公羊睾丸尺寸的影响。对季节性发情的基维里克羊和夏洛莱羊母羊及公羊进行褪黑素处理。两个品种经处理的母羊发情反应均显著高于对照母羊（p<0.001）。对照动物的妊娠率显著低于经处理的动物（p<0.001）。植入褪黑素的基维里克羊双羔率显著低于夏洛莱羊（p<0.05）。褪黑素处理42天后，两个品种的公羊睾丸尺寸均增大。基维里克羊和夏洛莱羊公羊的阴囊长度（SL）增加（p<0.01）。夏洛莱羊公羊阴囊周长（SC）的增加比基维里克羊公羊更显著（P<0.01）。基维里克羊（p<0.01）和夏洛莱羊（p<0.001）公羊的睾丸体积（TV）均大幅增加。本研究表明，植入褪黑素可使母羊发情时间比繁殖季节提前约四个月。在非繁殖季节植入褪黑素可显著增加基维里克羊和夏洛莱羊公羊的睾丸尺寸，从而提高其繁殖潜力。
