摘要
【目的】探究基于奶牛智能项圈系统产生的发情指数和活动峰值指标的群体规律及其影响因素,对其进行遗传参数估计,并利用全基因组关联分析(genome-wide association study, GWAS)挖掘与奶牛发情相关指标的遗传标记,以期为从遗传育种角度制定选育策略提高奶牛繁殖力提供有用信息。【方法】试验以北京市某规模化牧场健康的泌乳期荷斯坦牛为研究对象,收集了该牧场2017年7月至2020年5月2 074头泌乳牛的发情记录,包括发情指数和活动峰值,同时收集了试验牛的产犊记录;采用SAS 9.4中MIXED过程,分析了非遗传因素对发情指数和活动峰值的影响;基于DMU软件DMUAI模块,使用双性状动物模型估计了发情指数与活动峰值的遗传力及遗传相关,并计算了发情指数与常规繁殖性状的近似遗传相关;以逆回归育种值为关联分析的表型,利用Farm CPU软件分别对发情指数和活动峰值进行了GWAS。【结果】荷斯坦牛发情指数为(71.77±19.13)au,活动峰值为(105.94±30.73)au/2h。发情指数遗传力为0.04±0.01,活动峰值遗传力为0.19±0.04,均为低遗传力性状;发情指数与活动峰值之间的遗传相关为0.45±0.03;发情指数与经产牛首末次配种间隔、首次产犊日龄和青年牛首末次配种间隔的近似遗传相关分别为0.37、-0.41、-0.55。两个性状的GWAS共找到7个在全基因组水平上显著的SNP位点,分别位于7条染色体上,显著位点附近(300 kb内)共发现基因31个。【结论】通过项圈系统获得的发情指数和活动峰值是可遗传的,两者之间存在中等遗传相关,活动峰值为中低遗传力,且能够一定程度上反映奶牛的发情指数,活动峰值和发情指数为研究奶牛的发情行为以及提高母牛的繁殖力提供了新的方向。GWAS鉴定到的候选基因PTGS1(Prostaglandin-Endoperoxide Synthase1)和NDUFA8(Ubiquinone Oxidoreductase Subunit A8)的功能与供体胚胎总数有关,VEGFA(Vascular Endothelial Growth Factor A)基因功能与奶牛繁殖有关,可作为奶牛发情相关指标的候选基因进行深入研究。
【Objective】 The study was to explore population characteristics and influencing factors of heat index and activity peak based on cattle collar data and system and to estimate its genetic parameters, and to identify the genetic markers related to the estrus indicators of cow, the genetic analysis and GWAS were performed for heat index and activity peak, so as to provide useful information for improving dairy cow fertility by formulating breeding strategies from the perspective of genetic breeding.【Method】The heat index and activity peak records of 2 074 milking cows from a large-scale dairy farm in Beijing area were collected from July 2017 to May 2020. The MIXED model in SAS 9.4 was used to analyze the impacts of various factors on heat index and activity peak in Holstein cattle, and the DMUAI module of DMU software was used to estimate the heritability and genetic correlations of heat index and activity peak. The GWAS for heat index and activity peak was performed based on De-regressed Proof(DRP) using FarmCPU software. 【Result】 In Chinese Holstein cattle, the average heat index was(71.77±19.13) au, and the activity peak was(105.94±30.73) au/2 h. The heritability of heat index and activity peak was 0.04±0.01 and 0.19±0.04, respectively.The genetic correlation between heat index and activity peak was 0.45±0.03. The approximate heat index between the age at first calving in heifer, interval from first to last insemination, and interval from first to last insemination was 0.37,-0.41, and-0.55,respectively. The GWAS for heat index and activity peak identified seven significant single nucleotide polymorphism loci(SNP) at the genome level, and 31 genes nearby the significant SNP(within 300 kb) were found. 【Conclusion】 The heat index and activity peak obtained by collar system were heritable, and there was a moderate genetic correlation between them. The activity peak was of low heritability and could reflect the heat index of cows to some extent. The activity peak and heat index provided a new direction for studying and breeding the estrus behavior of cows and improving the fecundity of cows. The function of PTGS1(Prostaglandin-Endoperoxide Synthase1) and NDUFA8(Ubiquinone Oxidoreductase Subunit A8) genes identified by GWAS was related to the total number of donor embryos, and the function of VEGFA(Vascular Endothelial Growth Factor A) gene was related to the reproduction of cows.
作者
杨明路
张海亮
罗汉鹏
黄锡霞
张翰林
章施施
王炎
刘林
郭刚
王雅春
YANG MingLu;ZHANG HaiLiang;LUO HanPeng;HUANG XiXia;ZHANG HanLin;ZHANG ShiShi;WANG Yan;LIU Lin;GUO Gang;WANG YaChun(College of Animal Science and Technology,China Agricultural University/Key Laboratory of Animal Genetics/Breeding and Reproduction of Ministry of Agriculture and Rural Affairs/National Engineering Laboratory for Animal Breeding,Beijing 100193;College of Animal Science,Xinjiang Agricultural University,Urumqi 830052;Beijing Dairy Center,Beijing 100192;Beijing Sunlon Livestock Development Co.,Ltd,Beijing 100029)
出处
《中国农业科学》
CAS
CSCD
北大核心
2023年第5期995-1006,共12页
Scientia Agricultura Sinica
基金
国家现代农业产业技术体系(CARS-36)
长江学者和创新团队发展计划(IRT_15R62)
北京三元种业科技股份有限公司自立科研课题(SYZYZ20190005)。
关键词
繁殖性状
发情指数
活动峰值
遗传参数
全基因组关联分析
female fertility
heat index
activity peak
genetic parameter
genome-wide association study
