摘要
为了探讨A2型β-酪蛋白基因作为中国荷斯坦奶牛产奶性状和乳房性状候选基因的可能性,试验以467头中国荷斯坦奶牛为研究对象,采集血液样本,采用竞争性等位基因特异性PCR(KASP)方法对宁夏地区荷斯坦奶牛A2型β-酪蛋白基因多态性进行研究,并与奶牛产奶性状和乳房性状育种值进行关联分析。结果表明:从467头中国荷斯坦奶牛中共检测到2种A2型β-酪蛋白等位基因A1和A2,3种基因型A1A1、A1A2和A2A2。中国荷斯坦奶牛A2型β-酪蛋白基因未偏离Hardy-Weinberg平衡(P>0.05),呈中度多态(0.25<PIC<0.5)。A2基因为优势等位基因,等位基因频率为0.646;杂合A1A2基因型为优势基因型,基因型频率为0.437,纯合A2A2基因型的频率(0.426)仅次于杂合A1A2基因型。中国荷斯坦奶牛A2型β-酪蛋白基因与部分产奶性状和乳房性状显著相关(P<0.05),其中A1A1基因型奶牛的乳脂量和乳脂率育种值显著高于A2A2基因型(P<0.05),A2A2基因型奶牛的体细胞评分育种值最高(P<0.05)。A1A1基因型奶牛的前乳房附着和后乳房附着高育种值显著高于A2A2基因型(P<0.05)。说明A2型β-酪蛋白基因的多态位点有可能成为奶牛泌乳性状和乳房性状选育的分子标记。
To explore the possibility of A2 type β-casein gene as a candidate gene for milk production traits and udder traits of Chinese Holstein cows in China,467 Chinese Holstein dairy cows were used as subjects in this experiment.Blood samples were collected and the polymorphism of type A2 β-casein gene was studied by competitive allele-specific PCR(KASP)method in Holstein dairy cows from Ningxia region,and the association analysis was carried out with milk producing traits and udder traits breeding values.The results showed that two A2 β-casein alleles(A1 and A2)and three genotypes(A1 A1,A1 A2 and A2 A2)were detected from 467 Chinese Holstein dairy cows.The type A2 β-casein gene in Chinese Holstein cows did not deviate from Hardy-Weinberg equilibrium(P>0.05)and showed moderate polymorphism(0.25<PIC<0.5).The A2 gene was the dominant llele with a gene frequency of 0.646.The helerozygous A1A2 genotype was the dominant genotype with a genotype frequency of 0.437.The frequency of pure A2A2 genotype(0.426)was second only to heterozygous A1A2 genotype.The type A2 β-casein gene was significantly associated with some milk production traits and udder traits in Chinese Holstein cows(P<0.05),and the breeding value of milk fat content and milk fat percentage of A1A1 genotype cows was significantly higher than that of A2A2 genotype(P<0.05),and the breeding value of somatic cell score of A2A2 genotype was the highest(P<0.05).The breeding values of forebreast atachment and rear breast atachment height in A1 genotype were significantly higher than in A2 genotype.These results indicated that polymorphic loci of the type A2β-casein gene may be a molecular marker for lactation and udder traits selection in dairy cows.
作者
李艳艳
卜建华
韩丽云
张伟英
李青澄
母童
LI Yanyan;BU Jianhua;HAN Liyun;ZHANG Weiying;LI Qingcheng;MU Tong(Ningxia Agricultural Reclamation Helan Mountain Dairy Co.,Ltd.,Yinchuan 750205,China;Ningxia Agriculure and Forestry and Animal Husbandry Technology Extension Service Center,Yinchuan 750024,China;Agricultural College,Ningxia University,Yinchuan 750021,China)
出处
《黑龙江畜牧兽医》
CAS
北大核心
2022年第17期65-69,共5页
Heilongjiang Animal Science And veterinary Medicine
基金
宁夏自治区育种专项“优质高产奶牛选育项目”(2019NYYZ05)。
