Luo Jun, Wang Wei, Sun Shuang
Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China.
College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, Liaoning 110866, China.
Asian-Australas J Anim Sci. 2019 Aug;32(8):1284-1295. doi: 10.5713/ajas.19.0486. Epub 2019 Jul 18.
Considerable progress in reproduction of dairy goats has been made, with advances in reproductive technology accelerating dairy goat production since the 1980s. Reproduction in goats is described as seasonal. The onset and length of the breeding season is dependent on various factors such as breed, climate, physiological stage, male effect, breeding system, and photoperiod. The reproductive physiology of goats was investigated extensively, including hypothalamic and pituitary control of the ovary related to estrus behavior and cyclicity etc. Photoperiodic treatments coupled with the male effect allow hormone-free synchronization of ovulation, but the kidding rate is still less than for hormonal treatments. Different protocols have been developed to meet the needs and expectations of producers; dairy industries are subject to growing demands for year round production. Hormonal treatments for synchronization of estrus and ovulation in combination with artificial insemination (AI) or natural mating facilitate out-of-season breeding and the grouping of the kidding period. The AI with fresh or frozen semen has been increasingly adopted in the intensive production system, this is perhaps the most powerful tool that reproductive physiologists and geneticists have provided the dairy goat industry with for improving reproductive efficiency, genetic progress and genetic materials transportation. One of the most exciting developments in the reproduction of dairy animals is embryo transfer (ET), the so-called second generation reproductive biotechnology following AI. Multiple ovulation and ET (MOET) program in dairy goats combining with estrus synchronization (ES) and AI significantly increase annual genetic improvement by decreasing the generation interval. Based on the advances in reproduction technologies that have been utilized through experiments and investigation, this review will focus on the application of these technologies and how they can be used to promote the dairy goat research and industry development in the future.
自20世纪80年代以来，随着繁殖技术的进步加速了奶山羊的生产，奶山羊繁殖取得了显著进展。山羊的繁殖具有季节性。繁殖季节的开始和持续时间取决于品种、气候、生理阶段、雄性效应、繁殖系统和光周期等多种因素。人们对山羊的生殖生理学进行了广泛研究，包括下丘脑和垂体对与发情行为和周期性等相关的卵巢的控制。光周期处理与雄性效应相结合可实现无激素排卵同步，但产羔率仍低于激素处理。已经制定了不同的方案来满足生产者的需求和期望；乳制品行业对全年生产的需求不断增加。用于发情和排卵同步的激素处理与人工授精（AI）或自然交配相结合，有助于非繁殖季节的繁殖和产羔期的分组。在集约化生产系统中，越来越多地采用新鲜或冷冻精液进行人工授精，这可能是生殖生理学家和遗传学家为奶山羊产业提供的用于提高繁殖效率、遗传进展和遗传物质运输的最有力工具。奶畜繁殖中最令人兴奋的发展之一是胚胎移植（ET），这是继人工授精之后的所谓第二代生殖生物技术。奶山羊的多排卵和胚胎移植（MOET）计划与发情同步（ES）和人工授精相结合，通过缩短世代间隔显著提高了年度遗传进展。基于通过实验和研究已应用的繁殖技术的进展，本综述将重点关注这些技术的应用以及它们如何用于促进未来奶山羊的研究和产业发展。
