羊近交衰退的研究进展

Research progress of inbreeding depression in sheep

近交衰退是动物育种中必须考虑的因素之一。文章介绍了近交衰退产生的机制,以及近交对羊繁殖性状、生长性状和绒毛性状影响的研究进展。分析发现,除了绒毛品质(长度和细度)外,近交对所有分析性状均产生不利影响。近交显著降低母羊繁殖力和羔羊存活率,同时随着近交的增加,母羊产羔性能也略有下降,羔羊初生重、断奶重、2月龄体重、3月龄体重、6月龄体重、9月龄体重及周岁重均表现出不同程度的衰退。近交增加到一定程度后,对产绒量有不利效应,但对绒毛长度和细度无显著影响。

Inbreeding depression is one of the factors must be considered in animal breeding. This paper introduces the mechanisms of the gener- ation of inbreeding depression and the research progress of the effect of inbreeding on reproductive traits, growth traits and fleece traits of sheep. The analysis finds that inbreeding has negative effects on all analyzed traits except for the quality （length and fineness） of fleece. Inbreed sig- nificantly decreases ewe fertility and lamb survival rates, and ewe lambing performance decrease slightly with the increase in inbreeding. Mean- while, the birth weight, weaning weight, body weight at two, three, sixth, and nine months of age, and yearling body weight of lambs exhibits varying degrees of decline. After, inbreeding increases to a certain degree, it has a negative effect on fleece yield, but has no significant effect on the length and fineness of fleece.