Wang W, Luo J, Sun S, Xi L, Gao Q, Haile A B, Shi H, Zhang W, Shi H
Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, China.
Reprod Domest Anim. 2015 Feb;50(1):23-8. doi: 10.1111/rda.12444. Epub 2014 Nov 3.
The aim of this study was to evaluate whether the season of ejaculate collection influences seminal quality parameters of pre- and post-freeze-thawing in Xinong Saanen bucks. Ejaculates were collected from eight bucks throughout the four seasons (spring, summer, autumn and winter) in a 12 months' time period, identified in the Northern Hemisphere. Semen samples were evaluated by the combinations of conventional and Computer-Assisted Sperm Analysis (CASA) when fresh and after frozen-thawed, respectively. The results clearly demonstrated that season of ejaculate collection influenced (p < 0.05) fresh semen quality. Highest semen quality was observed during autumn. On the contrary, undesirable indices (significantly lower, p < 0.05) were observed in winter as compared with the other remaining seasons. CASA has clearly shown the influences of seasonal variations on semen motility parameters. Furthermore, season of ejaculate collection was also found to influence sperm freezability. Semen characteristics after frozen-thawed followed a similar pattern with that of fresh ejaculate except in spring. The results revealed that sperm quality was higher (p < 0.01) in summer and autumn than in spring and winter. In conclusion, seasonal variation influences semen quality in Xinong Saanen bucks. In addition to summer and autumn, fresh ejaculates in spring can also be successfully used for AI. Sperm from ejaculates collected during summer and autumn are more suitable for cryopreservation. Hence, it is possible to increase the efficiency of goat breeding by manipulating the seasonal variations of semen quality for immediate AI and/or cryopreservation.
本研究旨在评估采精季节对西农萨能种公羊冻融前后精液质量参数的影响。在北半球12个月的时间内，于春、夏、秋、冬四季从8只公羊采集精液。分别在精液新鲜时和冻融后，通过传统方法与计算机辅助精子分析（CASA）相结合的方式对精液样本进行评估。结果清楚地表明，采精季节对新鲜精液质量有影响（p<0.05）。秋季精液质量最高。相反，与其他季节相比，冬季出现了不理想的指标（显著更低，p<0.05）。CASA清楚地显示了季节变化对精液活力参数的影响。此外，还发现采精季节会影响精子的冷冻能力。除春季外，冻融后的精液特征与新鲜精液相似。结果显示，夏季和秋季的精子质量高于春季和冬季（p<0.01）。总之，季节变化会影响西农萨能种公羊的精液质量。除夏季和秋季外，春季的新鲜精液也可成功用于人工授精。夏季和秋季采集的精液中的精子更适合冷冻保存。因此，通过控制精液质量的季节变化以立即进行人工授精和/或冷冻保存，有可能提高山羊繁殖效率。
