敖汉细毛羊育种目标性状的确定及边际效益的计算

Determination of Breeding Objective Traits of Aohan Merino Sheep and Calculation of Their Marginal Benefit

[目的]为敖汉细毛羊的遗传选育提供理论依据。[方法]根据内蒙古赤峰市敖汉种羊场细毛羊群1997-2004年的早期性状和母羊产毛性状的鉴定记录，确定敖汉细毛羊的育种目标性状，并利用“差额法”对各育种目标性状的边际效益进行计算。[结果]从敖汉细毛羊3类性状（产毛性状、繁殖性状和生长发育性状）中共确定了6个育种目标性状，即净毛量、羊毛细度、羊毛长度、育成羊剪毛后体重、成年羊剪毛后体重、断奶羔羊数。其中成年母羊和育成羊净毛量的边际效益和相对重要性较大，分别为32．081、30．477和43．137％、36．870％。敖汉细毛羊产毛性状、繁殖性状、生长发育性状的相对重要性之比为7：2：1。[结论]净毛量是敖汉细毛羊最重要的育种目标性状。

[Objective] The aim was to provide the theoretical basis for genetic breeding of Aohan merino sheep. [Method] According to the identification record of early traits of merino sheep herd and wool waits of female merino sheeps from Aohan sheep breeding farm in Chifeng City of Inner Mongolia in 1997 - 2004, the breeding objective traits of Aohan merino sheep were detennined. And the marginal benefit of different breeding objective traits was calculated with difference method. [ Resuh ] From 3 kinds of characteristics （wool trait, reproductive traits, growth and development trait ） of Aohan merino sheep, 6 breeding objective waits such as wool yield, fiber diameter, fiber length, body weight after sheafing of yeanling group and adult sheep, number of weaned lambs were determined. Among which, the marginal benefit and relative value of wool yield of adult female sheep and yeanling sheep were bigger, being 32.081, 30.477 and 43.137 %, 36.870 % resp. The ratio of relative value of wool waits, productive trait and growth traits was 7：2：1. [ Conclusion] Wool yield was the most important breeding objective traits of Aohan merino sheep.