Reproduction Research Unit, U.S. Meat Animal Research Center, State Spur 18D, Clay Center, NE, 68933-0166, USA,
Adv Exp Med Biol. 2014;752:77-96. doi: 10.1007/978-1-4614-8887-3_4.
Animal breeding and reproductive physiology have been closely related throughout the history of animal production science. Artificial insemination provides the best method of increasing the influence of sires with superior genetics to improve production traits. Multiple ovulation embryo transfer (MOET) provides some ability to increase the genetic influence of the maternal line as well. The addition of genetic technologies to this paradigm allows for improved methods of selecting sires and dams carrying the best genes for production and yield of edible products and resistance to diseases and parasites. However, decreasing the number of influential parents within a population also increases the risk of propagating a recessive gene that could negatively impact the species (Reprod Domest Anim 44:792-796, 2009; BMC Genomics 11:337, 2010). Furthermore, antagonistic genotypic relationships between production traits and fertility (Anim Prod Sci 49:399-412, 2009; Anim Genet 43:442-446, 2012) suggest that care must be taken to ensure that increasing the frequency of genes with a positive influence on production does not negatively impact the fertility of the replacement females entering the herd.
动物繁殖和生殖生理学在动物生产科学的历史中一直密切相关。人工授精提供了增加具有优良遗传的父本影响以改善生产性状的最佳方法。多排卵胚胎移植（MOET）也提供了一些增加母系遗传影响的能力。将遗传技术添加到这个范例中，可以改进选择携带最佳生产和产量基因以及对疾病和寄生虫抗性的父本和母本的方法。然而，在种群内减少有影响力的父母数量也会增加传播可能对物种产生负面影响的隐性基因的风险（Reprod Domest Anim 44:792-796, 2009; BMC Genomics 11:337, 2010）。此外，生产性状和繁殖力之间的对抗基因型关系（Anim Prod Sci 49:399-412, 2009; Anim Genet 43:442-446, 2012）表明，必须小心确保增加对生产有积极影响的基因的频率不会对进入畜群的替代雌性的繁殖力产生负面影响。
