奶牛繁殖性状遗传学研究策略

Dairy farming

奶牛的繁殖力为数量性状,由微效多基因控制,受到遗传、管理、营养等多方面因素的影响。由于奶牛的繁殖力与产奶性状呈负遗传相关,并且低遗传力将导致选择效果不理想,使得奶牛繁殖性能在过去的20年间呈现缓慢衰退趋势,尤其在高产奶牛群体中表现突出。近年来,多个国家相继将部分繁殖性状引入奶牛综合选择指数,通过给予权重期望实现平衡育种的目标。本文从数量遗传学角度解析传统育种中对繁殖性状的选育,综述其与产奶性状以及其他功能性状的相关性,展示基因组选择时代繁殖性状的研究策略及应用前景。

Fertility traits in dairy cattle belong to quantitative traits, which follow polygene hypothesis and are likely to be affected by genetics, management and nutrition factors. Genetic correlations between milk yield and reproductive measures are negative. Along with an intense selection for increased milk yield, reproductive performance has declined in many countries during the past 20 years, especially in high producing dairy cows. However, the low heritability of fertility traits makes genetic improvement by traditional breeding programs slow. In recent years, aimed to achieve balance breeding system, most leading dairy countries have included the genetic progress of fertility into their comprehensive performance index for dairy cattle. For a quantitative genetics prospective, this paper focuses on genetic selection for fertility traits in conventional breeding, meanwhile, summarize the relationships between fertility and milk production traits as well as other important functional traits. Then, current review also presents the efficient strategies and opportunities for cattle fertility research in the era of genome.