基于标记系谱的青鱼生长性状的遗传参数估算

Genetic parameter estimation of growth traits in black carp (Mylopharyngodon piceus) by using a marker-based pedigree

  • 摘要:
    目的 本研究旨在评估青鱼生长性状的遗传参数,为制定良种选育路线提供依据。
    方法 以青鱼邗江群体为亲本,经人工繁殖构建F1代实验群体。18月龄时随机抽取566尾子代个体,利用已知青鱼SSR亲子鉴定标记进行系谱重建,结合体长和体重表型数据,采用动物模型和约束极大似然法估计遗传参数。
    结果 566尾子代个体中的551尾被成功分配到242个全同胞家系,实际鉴定成功率97.35%。体长、体重的遗传力分别为0.48和0.43,均属于高遗传力。体长和体重间的表型相关和遗传相关分别为0.81和0.92,两个生长性状之间高度相关。
    结论 研究表明,现有SSR标记可以准确鉴定青鱼亲子关系,18月龄青鱼在体重和体长性状中具有较高选育潜力,可为后续良种选育提供支持。

     

    Abstract: Mylopharyngodon piceus is an important commercial freshwater aquaculture species in China, yet no improved variety has been successfully bred to date, resulting in an urgent demand for selective breeding. This study aimed to estimate genetic parameters of growth traits in M. piceus to provide a basis for formulating breeding strategies. An F1 experimental population was established through artificial propagation using the Hanjiang population of M. piceus as broodstock. At 18 months of age, 566 offspring individuals were randomly sampled, and pedigree reconstruction was performed utilizing existing SSR parentage identification markers for this species. Combining the marker-based pedigree with phenotypic data of body length and body weight, genetic parameters were estimated using an animal model and the restricted maximum likelihood (REML) method. Among the 566 offspring, 551 were successfully assigned to 242 full-sib families, yielding an assignment success rate of 97.35%. The heritability estimates for body length and body weight were 0.48 and 0.43, respectively, both classified as high heritability. The phenotypic correlation coefficient between body length and body weight was 0.81, and the genetic correlation coefficient reached 0.92, indicating a high degree of correlation between these two growth traits. These results demonstrate that the available SSR markers can accurately determine parentage in M. piceus, and that 18-month-old M. piceus exhibit considerable selection potential for body weight and body length, thereby supporting future selective breeding programs for genetic improvement.

     

/

返回文章
返回