鲁中肉羊不同生长阶段体尺体重的遗传参数估计

Estimation of genetic parameters of body size and body weight at different growth stages of Luzhong mutton sheep

估计鲁中肉羊不同生长阶段体尺、体重的遗传参数,分析各性状间的遗传规律,以期为鲁中肉羊育种规划工作提供理论依据。收集2015—2019年共15 040条鲁中肉羊体尺、体重数据,以初生、3月龄、6月龄、周岁和成年阶段的体重、体高、体长、胸围、胸宽、胸深、管围性状为研究对象,利用DMU软件中AI-REML结合EM算法并配合动物模型,以出生年份、出生季节和性别为固定效应,以加性效应和母体效应为随机效应,估计各性状的遗传力和遗传相关。结果表明,初生至成年阶段鲁中肉羊的体重的遗传力为0.18~0.51,体高的遗传力为0.15~0.60,体长的遗传力为0.09~0.42,胸围的遗传力为0.11~0.43,胸宽的遗传力为0.05~0.39,胸深的遗传力为0.06~0.21,管围的遗传力为0.11~0.59,初生至6月龄阶段母体遗传力为0.15~0.26,不同阶段性状间遗传相关系数-0.52~0.98,表型相关系数为-0.05~0.95,不同生长阶段间体重的遗传相关系数为-0.10~0.87,表型相关系数为0.01~0.91。综上,母体遗传效应对鲁中肉羊早期生长性状影响较大,随着成长母体遗传效应逐步减弱,周岁阶段体重遗传力在本研究中最高,不同生长阶段体尺体重间存在中到高的遗传相关,各生长阶段间6月龄与周岁阶段体重遗传相关系数最高。

The objective of this study is to estimate the genetic parameters of body size and body weight of Luzhong mutton sheep at different growth stages,and to analyze the genetic rules between various traits,in order to provide a theoretical basis for the breeding planning of Luzhong mutton sheep.A total of 15 040 Luzhong mutton sheep body size and body weight data were collected from 2015 to 2019,and the body weight,body height,body length,chest circumference,chest width,chest depth,and cannon circumference traits of firstborn,3 months,6 months,one year and adult stage were taken as the research objects,and AI-REML combined with EM algorithm in DMU software was used to cooperate with animal models,taking birth year,birth season and sex as fixed effects,and additive effect and maternal effect as random effects,to estimate the heritability and genetic correlation of each trait.The heritability of Luzhong meat sheep weight from fristborn to adult was 0.18-0.51,the heritability of body height was 0.15-0.60,the heritability of body length was 0.09-0.42,the heritability of chest circumference was 0.11-0.43,the heritability of chest width was 0.05-0.39,the heritability of chest depth was 0.06-0.21,the heritability of cannon circumference was 0.11-0.59,and the maternal heritability of the firstborn to 6 months was 0.15-0.26,the genetic correlation coefficient between traits at different stages was-0.52-0.98,and the phenotypic correlation was-0.05-0.95.The genetic correlation coefficient of body weight between different growth stages was-0.10-0.87,and the phenotype correlation was 0.01-0.91.The maternal genetic effect had a high influence on the early growth traits of Luzhong meat sheep,and with the gradual weakening of the maternal genetic effect of growth,the heritability of body size and body weight of one year old was the highest in this study,and there was a genetic correlation between body size and body weight at different growth stages.The genetic correlation coefficient between 6 months old and one year old was the highest among the growth stages.