中国瘦肉猪新品系DⅣ系不同近交程度对经济性状的影响

The influence of different degrees of inbreeding on economic traits in the new line (DⅣ) of Chinese lean-type plgs:

根据中国瘦肉猪新品系ＤⅣ系群猪的研究资料，我们逐头计算了个体近交系数，然后按近交系数（％）高低依次分为０～０．７８，０．７９～１．５６，１．５７～３．１２，３．１３～６．２４，６．２５～１２．４，１２．５～２５等６个组，对各项繁殖性状、肥育性状、胴体性状与肉质性状进行了分组统计和方差分析。结果表明：当近交系数在６．２４％～１２．４％范围内时，后备猪生长发育和同胞测定猪的肥育性能表现最佳，当近交系数大于１２．５％时，主要经济性状出现下降趋势。

Individual inbreeding coefficient was calculated in the population of new DⅣ line of the Chinese lean pig. Inbreeding coefficient (%) was divided into six groups: 0～0.78,0.79～1.56,1.57～3.12,3.13～6.24,6.25～12.4,12.5～25. Reproductive, fattening and carcass in each group were analyzed by analysis of group and variance. Results showed that replacement pigs could acquire maxmum fattening performance according to sib test when inbreeding coefficient was in the rang of 6.24%～12.4%. The major ecomomic traits displayed a declining tendency if the coefficient was larger than 12.5%.