日本囊对虾早期生长性状遗传参数估计

Genetic parameter estimation of growth traits for early growth stage of Marsupenaeus japonicus

基于68个日本囊对虾(Marsupenaeus japonicus)全同胞家系,采用混合线性模型和约束极大似然法对日本囊对虾生长性状进行遗传参数的估计。结果表明:1)45日龄、75日龄体长性状的遗传力估计值分别为0.1545±0.0505、0.1933±0.0475,腹节长性状的遗传力估计值分别为0.1672±0.0473、0.1937±0.0468,体重性状的遗传力估计值分别为0.1934±0.0439、0.1992±0.037,均为中等遗传力;2)不同日龄下日本囊对虾生长性状间的表型相关与遗传相关均为高度正相关,45日龄体长–腹节长、体长–体重、腹节长–体重的表型相关为0.7121±0.0188、0.5147±0.0277、0.5052±0.0280,遗传相关为0.9896±0.00340、0.9304±0.0321、0.9429±0.0301,75日龄体长–腹节长、体长–体重、腹节长–体重的表型相关为0.6710±0.0236、0.6555±0.0181、0.6534±0.0160,遗传相关为0.7637±0.0161,0.7479±0.0148,0.7177±0.0131。本研究表明对日本囊对虾生长性状进行选择是有效的,以体长、腹节长、体重任一性状作为指标进行选育均可达到生长改良的目的,本研究结果可为日本囊对虾的早期选择育种和多性状选择提供数据参考。

Linear Mixed Effects Model and Restricted Maximum Likelihood （REML） were applied to estimate the genetic parameters for growth traits based on sixty-eight fuli-sib families of the Kuruma shrimp Penaeus Marsu- penaeus japonicus. The results indicated that the heritability estimates of body length （BL）, abdorminal segment length （ASL）, and body weight （BW） were 0.1545±0.0505, 0.1672±0.0473, and 0.1934±0.0439, respectively, on day 45. On day 75, the heritability estimates were 0.1933±0.0475 for body length, 0.1937±0.0468 for abdorminal segment length, and 0.1992±0.037 for body weight, all of which were found to be at moderate levels. Strong posi- tive phenotypic and genetic correlations between growth-related traits at different stages were detected. The phe- notypic correlations between BL and ASL, BL and BW, and ASL and BW on day 45 were 0.7121±0.0188, 0.5147± 0.0277, and 0.5052±0.0280, respectively, while the genetic correlations were 0.9896±0.0034, 0.9304±0.0321, and 0.9429±0.0301, respectively. The phenotypic correlations between BL and ASL, BL and BW, and ASL and BW on day 75 were 0.6710±0.0236, 0.6555±0.0181, and 0.6534±0.0160, respectively, while the genetic correlations were 0.7637±0.0161, 0.7479±0.0148, and 0.7177±0.0131, respectively. Selection for growth traits in M. japonicus was found to be effective in the present study, and selection for one growth trait can improve other growth traits simultaneously in a breeding program. The results of this study provided reference data for early selective breeding and multi-trait selection ofM. japonicus.