不同模型估计牙鲆家系间生长性状遗传参数的比较分析

Comparison and analysis of genetic paramaters of growth traits estimatied by different models for Japanese flounder families

利用中国水产科学研究院北戴河中心实验站2006～2009年间牙鲆选育家系240日龄生长性状的测定记录，对4种不同动物模型估计的生长性状遗传参数进行了比较分析。不同模型分别包括了加性遗传效应、母体遗传效应和全同胞效应。利用MTDFREML程序采用非求导约束极大似然法（DFREML）估计各模型中的方差组分。用似然比检验对不同模型的差异进行检验。结果显示，对于牙鲆240日龄体重、体长和体高，母体遗传效应和全同胞效应都有显著的影响，应用模型Ⅳ进行分析，体重、体长和体高的遗传力分别为0．30、0．32和0．39。体重与体长、体高的正向遗传相关分别为0．93和0．95；体长与体高的正向遗传相关为0．90。

Testing records of growth traits in 240-day age Japanese flounder selective breeding families between 2006 and 2009 at the Beidaihe Central Experiment Station, Chinese Academy of Fishery Sciences, were used to analyze the genetic parameters of growth traits by 4 different animal models. The four models examined additive genetic effect, maternal genetic effect and full-sib effect. The variance components in different models were estimated with the derivative free restricted maximum likelihood （DFREML） method using MTDFREML soft- ware. The differences between different models were tested by likelihood ratio test. The results showed that the maternal genetic effect and full-sib effect were significant for body weight （BW）, body length （BL） and body depth （BD）, and the model Ⅳ should be adopted for analysis. The heritability of BW, BL and BD was 0.30, 0.32 and 0.39, respectively. Positive genetic correlations were found between BW and BL, BW and BD, at values of 0.93 and 0.95 respectively. The positive genetic correlations between BL and BD were 0.90.