肉牛基因组遗传评估

The Genetic Evaluation of Beef Cattle Genome

利用最佳线性无偏估计(BLUP)方法估算级进杂交的F2代及以上公、母牛各性状及综合育种值,评估不同肉牛育种值变化的遗传趋势,为制定合理的育种方案,逐步改良牛群的缺陷性状提供依据。该评估根据国内肉牛育种数据的实际情况。整理产犊难易度、断奶重、育肥期日增重、胴体重、屠宰率共5个主要性状,进行肉牛基因组育种值估计,基因组估计育种值(GEBV)经标准化后,加权得到中国肉牛基因组选择指数(GCBI)。结果显示,此次评估的30头母牛有8头公牛GCBI值超过100,在已测群体中排名整体较为靠前,其中6号牛在5个性状中的胴体重和屠宰率的基因组育种值排名较高;评估的20头公牛有7头公牛GCBI值超过100,在已测群体中排名整体较为靠前,其中2号牛在5个性状中的产犊难易度和胴体重的基因组育种值排名较高,4号牛在5个性状中的胴体重和育肥期日增重的基因组育种值排名较高。

Using the BLUP(Best Linear Unbiased Estimation)method to estimate the various traits and comprehensive breeding values of F2 generation and above male and female cattle in progressive hybridization,evaluate the genetic trend of changes in breeding values of different beef cattle,and provide a basis for formulating reasonable breeding plans and gradually improving the defect traits of cattle populations.Based on the actual situation of domestic beef cattle breeding data,this evaluation estimates the genomic breeding value of beef cattle for five main traits:calving difficulty,weaning weight,daily gain during fattening period,carcass weight,and slaughter rate.After standardization,the genomic estimated breeding value(GEBV)is weighted to obtain the Genomic China Beef Index(GCBI)for Chinese beef cattle.The results showed that out of the 30 cows evaluated in this study,8 bulls had GCBI values exceeding 100,ranking relatively high in the tested population as a whole.Among them,the genome breeding values of the carcass weight and slaughter rate of Cattle 6 were higher among the five traits;Out of the 20 bulls evaluated in this evaluation,7 had a GCBI value exceeding 100,ranking relatively high in the tested population as a whole.Among them,the genome breeding values for calving difficulty and carcass weight of the 2nd bull were higher among the five traits,while the genome breeding values for carcass weight and daily gain during fattening period of the 4th bull were higher among the five traits.