红鳍东方鲀(Takifugu rubripes)生长性状的遗传参数估计

Estimation of Genetic Parameters of Growth Traits of Redfin puffer(Takifugu rubripes)

通过人工受精的方法获得红鳍东方鲀8个半同胞家系(16个全同胞家系),共测量了790尾红鳍东方鲀8个半同胞家系(16个全同胞家系)135日龄和200日龄的体质量和体长。将135日龄生长性状作为协变量构建3个动物模型,模型(1)包含加性遗传效应、母本遗传效应和全同胞效应;模型(2)包含加性遗传效应和母本遗传效应;模型(3)包含加性遗传效应和全同胞效应。利用DMU软件,采用平均信息约束极大似然法估计各模型中性状的方差组分,用似然比检验法进行不同模型的差异检验。选择最优模型估计红鳍东方鲀200日龄生长性状的遗传参数。结果表明,母本遗传效应对200日龄红鳍东方鲀生长性状无显著影响,确定模型(3)为最优模型。200日龄红鳍东方鲀,体质量和体长的遗传力分别为0.16和0.14,全同胞效应比率分别为0.12和0.13。研究表明,红鳍东方鲀生长性状具备一定的选择潜力,应用家系选育方法能够获得较好的遗传进展。

Redfin puffer is an important marine fish species and is widely cultured in China, Korea and Japan because of its high edible value. It is common that in the development of redfin puffer aquaculture cultivated fingerlings showed slow growth rate and poor resistance to disease. To improve the traits of interest, accurate estimation of their genetic parameters is needed to develop selective breeding programs. However, the heritability of different growth traits in redfin puffer has been rarely reported so far. In this study, we generated eight half-sib families （16 full-sib families） of redfin puffer Takifugu rubripes with artificial insemination to select the optimal model of genetic evaluation and to acquire accurate and reliable genetic parameters of the growth traits. Two growth traits of 790 redfin puffers from these families were measured, including the body weight and the body length. The growth traits at 135 days of age were used as covariates to construct three animal models as below：in model （1） the additive genetic effect, the maternal genetic effect and the family effect were considered;in model （2） the additive genetic effect and the maternal genetic effect were included;and in model （3） the additive genetic effect and the family effect were analyzed. DMU software was applied to estimate the variance components in each model with the average information restricted maximum likelihood method, and the differences between the three models were analyzed with the likelihood ratio test. The optimal model was used to estimate the genetic parameters of growth traits at 200 days of age in redfin puffer. The results showed that the maternal effect was significant in none growth traits at 200 days of age. Thus, the optimal model should be model （3）. At 200 days of age, the body weight and the body length showed heritability of 0.16 and 0.14 respectively, and full-sib effect ratio of 0.12 and 0.13 respectively. These results suggested that there could be a certain potential for growth traits during artificial selection and that family breeding could effectively improve these traits in redfin puffer.