Bezjian Marisa, Abou-Madi Noha, Kollias George V, Parks John E, Cheong Soon Hon, Beltaire Katherine A
Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York 14853, USA.
J Zoo Wildl Med. 2013 Sep;44(3):672-85. doi: 10.1638/2012-0267R.1.
The aims of this study were to determine the reproductive seasonality of four captive markhor goats (Capra falconeri heptneri), to characterize semen collected by electroejaculation, and to compare extenders and processing techniques for semen cryopreservation. Over the course of 1 yr, mean monthly scrotal circumference, serum testosterone, and fecal testosterone were measured and found to be inversely associated with day length. Maximum scrotal circumference (25.2 +/- 0.9 cm), serum testosterone (521.0 +/- 103.4 ng/dl), and fecal testosterone (382.5 +/- 90.3 ng/g) occurred in November, when day length was short (9.7 +/- 0.1 hr). Once a month for 3 mo (December, January, and February), bucks were anesthetized for electroejaculation and semen evaluation. Semen samples were divided into six aliquots for extension and cryopreservation in soy-based Bioxcell or Tris-based extender with 5 or 15% egg yolk, with and without centrifugation. Samples were then thawed for repeat evaluation 1-3 mo later. Postthaw evaluation revealed no significant differences between centrifuged and noncentrifuged samples. Sperm in Tris 5% and 15% egg yolk displayed higher total motility at 0, 3, and 6 hr postthaw and higher progressive motility postthaw compared with sperm in Bioxcell (P < 0.05). Sperm in Bioxcell displayed higher viability than sperm in both Tris-egg yolk extenders (P < 0.01), more intact acrosomes than sperm in Tris-15% egg yolk (P < 0.05), and a tendency for more intact acrosomes than sperm in Tris-5% egg yolk (P < 0.10). Sperm in Tris-5% egg yolk tended to have a higher percentage of morphologically normal sperm compared with Bioxcell (P < 0.10). This study provides evidence that markhor goats exhibit seasonality in scrotal circumference and testosterone levels and that centrifugation may be eliminated from the processing of markhor semen.
本研究的目的是确定四只圈养捻角山羊（Capra falconeri heptneri）的繁殖季节性，对电刺激采得的精液进行特性分析，并比较精液冷冻保存的稀释液和处理技术。在1年的时间里，测量了平均每月阴囊周长、血清睾酮和粪便睾酮，发现它们与日长呈负相关。最大阴囊周长（25.2±0.9厘米）、血清睾酮（521.0±103.4纳克/分升）和粪便睾酮（382.5±90.3纳克/克）出现在11月，此时日长较短（9.7±0.1小时）。在3个月（12月、1月和2月）里，每月对雄羊进行一次麻醉以进行电刺激采精和精液评估。精液样本被分成六等份，分别用含5%或15%蛋黄的大豆基Bioxcell或Tris基稀释液进行稀释和冷冻保存，有无离心处理。然后在1 - 3个月后将样本解冻进行重复评估。解冻后评估显示，离心和未离心样本之间没有显著差异。与Bioxcell中的精子相比，Tris 5%和15%蛋黄中的精子在解冻后0、3和6小时的总活力更高，解冻后的前进运动能力也更高（P<0.05）。Bioxcell中的精子活力高于两种Tris - 蛋黄稀释液中的精子（P<0.01），顶体完整率高于Tris - 15%蛋黄中的精子（P<0.05），且有高于Tris - 5%蛋黄中精子的趋势（P<0.10）。与Bioxcell相比，Tris - 5%蛋黄中的精子形态正常精子百分比有更高的趋势（P<0.10）。本研究提供了证据，表明捻角山羊在阴囊周长和睾酮水平上表现出季节性，并且在捻角山羊精液处理过程中可以省去离心步骤。
