“鲆优1号”牙鲆生长和育种性能分析及亲本选留

Analysis of growth performance and breeding value of "Ping You No.1" Japanese flounderand selection of parents

对"鲆优1号"牙鲆(Paralichthys olivaceus)进行育种性能分析,并研究育种值选择在牙鲆育种中的应用。测量了2 425尾450日龄左右"鲆优1号"牙鲆全长和体质量。采用SPSS软件进行表型参数分析,运用DMU软件,采用REML法进行方差组分估计,并通过BLUP方法预测个体估计育种值(EBV)。根据表型值和育种值的比较结果进行亲本选留。结果显示,运用DMU软件包估计牙鲆全长和体质量遗传力分别为0.266、0.302。全长、体质量育种值与表型值相关系数分别为0.685和0.677,都表现为极显著相关(P<0.01)。经家系间比较,"鲆优1号"牙鲆的表型值均值和育种值均值都高于其他家系,表现出了明显的生长优势和很好的育种性能。按照30%的选择强度分别根据育种值、表型值选留优良家系,两种方式选留家系的相同率为71.43%。将育种值选择与表型值选择进行比较发现,全长和体质量的育种值选择效率分别比表型选择高35.38%、32.29%,说明育种值选择优于表型选择。

The Japanese flounder （Paralichthys olivaceus） is widely cultured throughout the coastal areas of North China. In recent years, the species has exhibited growth rate depression, decreased fertility, and decreased disease resistance because of a number of factors, including changes in the environment and decreased quality of parent fish. Thus, the development of fast-growing offspring by cross breeding and selection would aid the sustainable development of the Japanese flounder culture industry. We used several parental lines of Japanese flounder with the traits of disease resistance and fast growing and Korea stock （KS） to establish 24 families, including a ＂Ping You NO.l＂ family. We measured the total length and body weight of these families at 450 days after hatching. We estimated the heritability of total length and body weight using a restricted maximum likelihood approach. The breeding value of all animals at 450-day was predicted using best linear unbiased prediction. The heritability of total length and body weight were 0.266 and 0.302, respectively, suggesting both traits have moderate heritability. The correlation coefficients between breeding values and phenotypic values of the growth traits were 0.685 and 0.677 （both P〈0.01）. Both growth and breeding ability were higher in Ping You No. 1 than in the other families. We used a selection standard of-30%, and found that 71.43% families of all were the same, selected based on breed- ing value and phenotypic value, respectively. Comparison of selection efficiency based on breeding value or phe- notypic value revealed that the breeding value was better than the phenotypic value for growth traits： 35.38% to total length and 32.29% to body weight.