应用动物模型BLUP方法估计猪个体育种值研究

Studies on Predicting Breeding Value of Swine Applying BLUP animal Model

利用华中农业大学养猪科学研究所的中国瘦肉猪新品系DⅣ系 1986～ 1992年期间测定资料 1747条、繁殖性能资料 5 2 0条和系谱资料 ,对日增重、背膘厚、边膘厚、总产仔数、产活仔数、初生窝重 6个性状进行了详细的遗传统计分析。用非求导的REML方法 (MTDFREML软件 )估计了这些性状的不同遗传模型条件下的遗传力及性状间的遗传相关系数和表型相关系数。用BLUP方法 (PEST软件 )估计这些性状的育种值 ,并计算遗传进展。日增重、背膘厚和边膘厚遗传力分别为 0 .41、0 .47和 0 .42 ,日增重和背膘厚两性状间表型相关和遗传相关分别为 0 .0 2和 - 0 .0 2 ,背膘厚和边膘厚遗传相关为 0 .99。而繁殖性状总产仔数、产活仔数、初生窝重的遗传力分别是 0 .0 9、0 .12和 0 .2 1。日增重、背膘厚、边膘厚、总产仔数、产活仔数、初生窝重遗传进展分别为 3g/d、- 0 .14mm、- 0 .13mm、0 .0 13头、0 .0 2头和 0 .0 3kg。中国瘦肉猪新品系DⅣ系采用群体继代选育法 ,经 6个世代的选育 。

Data of 1747 testing records and 520 reproduction records and pedigree information of the new line (DⅣ) in Chinese lean type pigs between 1986～1992 in Huazhong Agricultural University were used to make detailed genetic and statistical analysis on six traits including average daily gain(ADG), backfat thickness(BF1), side backfat thickness(BF2), total number of birth(TNB), number of born alive(NBA) and litter weight of birth(WB). Genetic parameters of six traits were estimated with a multiple trait derivative free restricted maximum likelihood (MTDFREML) procedure under different genetic models. A individual breeding value of above traits was evaluated using best linear unbiased prediction and genetic trend was estimated from those predicted breeding value. Heritabilities of ADG, BF1 and BF2 were 0.41, 0.47 and 0.42, respectively. Phenotypic and genetic correlation between ADG and BF1 were 0.02 and -0.02 respectively. Genetic correlation between BF1 and BF2 was 0.99. Heritabilities of TNB, NBA and WB were 0.09, 0.12 and 0.21, respectively. Genetic trend of ADG, BF1, BF2, TNB, NBA and WB were 3 g/d,-0.14 mm,-0.13 mm,0.013 piglet,0.02 piglet and 0.03 kg respectively. New line (DⅣ) in Chinese lean type pigs, which was formed by closed herd breeding, had somewhat genetic trends through six generations selection in main economical traits. \;