Department of Animal Production, College of Food and Agriculture Sciences, King Saud University, P.O. Box 2460, Riyadh, 11451, Saudi Arabia; Department of Theriogenology, Faculty of Veterinary Medicine, Zagazig University, 44519, Egypt.
Department of Animal Production, College of Food and Agriculture Sciences, King Saud University, P.O. Box 2460, Riyadh, 11451, Saudi Arabia; Department of Physiology, Faculty of Veterinary Medicine, Zagazig University, 44519, Zagazig, Egypt.
Anim Reprod Sci. 2018 Aug;195:334-344. doi: 10.1016/j.anireprosci.2018.06.014. Epub 2018 Jun 25.
The effects of a shortened photoperiod on the reproductive performance and hormones of mature dromedary camel bulls (Camelus dromedarius) were evaluated. A group of 6 bulls were blindfolded to induce a daily photoperiod that was ∼2.55 h shorter than the natural day length (10.83L:13.17D), whereas 6 others served as the control group. The trial started in June and continued for 10 weeks during the non-breeding season. The reproductive performance of all animals was evaluated weekly during this time and also during the breeding season, starting in December and continuing for 10 weeks. Camel bulls in the treatment group showed a significant (p < 0.05) increase in testicular volume, scrotal circumference, sexual desire, reaction time, and mating ability scores, and serum melatonin and testosterone concentrations, relative to the control group, during the non-breeding season. In addition, sexual desire and reaction time and mating ability scores were significantly (p < 0.05) higher in the treatment group than in the control during the breeding season. There was no significant difference between the treatment groups in both seasons and the control group in the breeding season regarding semen volume, sperm cell concentration, total motility, progressive motility, plasma membrane integrity, and viability. Shortening the daily photoperiod by blindfolding can improve the reproductive performance of dromedary camel bulls during the non-breeding season and the following breeding season. This simple, inexpensive, and easily applicable method can enable breeders to collect semen of acceptable quality during the non-breeding season.
研究了缩短光周期对成熟单峰驼公牛（Camelus dromedarius）繁殖性能和激素的影响。将 6 头公牛蒙上眼睛，人为将每天的光周期缩短约 2.55 小时，短于自然日长（10.83L:13.17D），而另外 6 头作为对照组。试验于 6 月开始，在非繁殖季节持续 10 周。在此期间，每周评估所有动物的繁殖性能，并在 12 月开始的繁殖季节继续评估 10 周。在非繁殖季节，与对照组相比，处理组的公牛睾丸体积、阴囊周长、性欲、反应时间和配种能力评分以及血清褪黑素和睾酮浓度显著增加（p<0.05）。此外，在繁殖季节，处理组的性欲、反应时间和配种能力评分显著高于对照组（p<0.05）。在两个季节中，处理组和对照组的精液量、精子细胞浓度、总活力、前向运动活力、质膜完整性和活力均无显著差异。用蒙眼的方法缩短每日光周期可以提高单峰驼公牛在非繁殖季节和随后的繁殖季节的繁殖性能。这种简单、廉价且易于应用的方法可以使饲养员在非繁殖季节收集到可接受质量的精液。
