西门塔尔牛与我国地方黄牛的杂种优势预测分析

旨在利用覆盖全基因组和与性状相关的SNPs标记分析西门塔尔牛和地方黄牛两个亲本群体的遗传结构,通过亲本种群之间的遗传距离预测不同杂交组合在生长、胴体和肉质性状上的杂种优势.本研究选择来自内蒙古锡林郭勒盟乌拉盖管理区牧场的1 222头西门塔尔牛和8个地方黄牛品种190头共组成8个杂交组合,对亲本群体进行遗传结构分析.利用...

Prediction of Heterosis between Chinese Simmental Beef Cattle and Chinese Local Cattle

The study aimed to analyze the genetic structure of parental lines of Chinese Simmental beef cattle and Chinese local cattle by the 770K SNP markers covering the whole genome of cattle and trait-related SNP markers,and predict heterosis of different hybrid combinations in growth,carcass and meat quality traits by genetic distance(GD)of parental lines.One thousand two hundred and twenty-two Chinese Simmental beef cattle in Ulgai of Xilin Gol League,Inner Mongolia and 8 Chinese local cattle breeds including 190 were selected to form 8 hybrid combinations,and the genetic structure of parental lines were analyzed.Parent populations were genotyped using Illumina BovineHD SNPs array(770K).The QTLs corresponding to the target traits were screened by cattle QTL database and the SNP loci of the whole genome were mapped to obtain trait-related SNP markers.The state homology matrix was constructed by using SNP markers,and the genetic distance between the parent lines of each hybrid combination was calculated.All parent lines were clustered into 3 groups,Chinese Simmental beef cattle was clustered into one category,northern cattle(Menggu cattle,Xizang cattle and Chaidamu cattle)and southern cattle(Zhaotong cattle,Pingwu cattle,Nandan cattle,Wenshan cattle and Liangshan cattle)were clustered into one category,respectively.Chinese Simmental beef cattle and northern breeds of Chinese local cattle were relatively closer on the PCA map,indicating that the genetic relationship between them was relatively closer,and the difference in the genetic background was smaller.Among all the traits,the parent combinations with the largest genetic distance were Chinese Simmental beef cattle and Nandan cattle.The genetic distance between Chinese Simmental beef cattle and Zhaotong cattle was the smallest for marbling score,and the smallest genetic distance of other traits was all between Chinese Simmental beef cattle and Pingwu cattle.In summary,the possible combination with better heterosis in all traits was between Chinese Simmental beef cattle and Nandan cattle.