Abstract USDA National Animal Germplasm Program is responsible for collecting germplasm from agriculturally relevant species in the US and developing methods for its efficient and effective storage and utilization. Lack of low cost and effective use of assisted reproductive technologies in sheep has been problematic and impacts the effective use of germplasm. While ram semen can be cryopreserved, methods for its use via non-surgical artificial insemination (AI) are not well developed. Consequently, we performed multiple trials to identify methods that result in ewe fertility when using cryopreserved ram semen, synchronized estrous, and timed non-surgical AI to identify factors that influence fertility. Experiment 1 used Black Welsh Mountain sheep and resulted in 51 % of bred ewes lambing. Statistical analysis showed age of the ewe, ram, and interaction of ewe age X time of AI effects were not significant. However, AI time relative to CDIR removal impacted fertility (P 0.05). Experiment 3 utilized both breeds of sheep and resulted in mean fertility of 48 and 13 % for Black Welsh Mountain and Rambouillet, respectively. Analysis of the fertility results in experiment 3 included the effects of ewe breed, time of AI, ram, and the 2 and 3-way interaction terms. The three-way interaction of ewe breed X ewe age class X AI time was significant (P

中文翻译：

---

绵羊非手术人工授精的关键因素

摘要 美国农业部国家动物种质计划负责从美国农业相关物种中收集种质，并开发有效储存和利用的方法。绵羊辅助生殖技术缺乏低成本和有效利用一直是一个问题，并影响了种质资源的有效利用。虽然公羊精液可以冷冻保存，但通过非手术人工授精 (AI) 使用的方法还没有得到很好的发展。因此，我们进行了多项试验，以确定在使用冷冻保存的公羊精液、同步发情和定时非手术 AI 来确定影响生育能力的因素时导致母羊生育能力的方法。实验 1 使用了黑威尔士山羊，结果是 51% 的母羊产羔。统计分析显示母羊、公羊、母羊年龄X时间交互作用不显着。然而，相对于 CDIR 去除的 AI 时间影响了生育能力（P = 0.05）。实验 3 使用了两个品种的绵羊，结果 Black Welsh Mountain 和 Rambouillet 的平均生育率分别为 48% 和 13%。实验 3 中生育力结果的分析包括母羊品种、AI 时间、公羊以及 2 和 3 种交互作用项的影响。母羊品种X母羊年龄等级XAI时间三元交互作用显着（P 实验 3 中生育力结果的分析包括母羊品种、AI 时间、公羊以及 2 和 3 种交互作用项的影响。母羊品种X母羊年龄等级XAI时间三元交互作用显着（P 实验 3 中生育力结果的分析包括母羊品种、AI 时间、公羊以及 2 和 3 种交互作用项的影响。母羊品种X母羊年龄等级XAI时间三元交互作用显着（P