Su Minqiang, Lin Xiaojue, Xiao Zupeng, She Yuanhang, Deng Ming, Liu Guangbin, Sun Baoli, Guo Yongqing, Liu Dewu, Li Yaokun
College of Animal Science, South China Agricultural University, Guangzhou 510642, China.
National Local Joint Engineering Research Center of Livestock and Poultry, South China Agricultural University, Guangzhou 510642, China.
Animals (Basel). 2023 Aug 7;13(15):2545. doi: 10.3390/ani13152545.
Lactation traits are economically important for dairy cows. Southern China has a high-temperature and high-humidity climate, and environmental and genetic interactions greatly impact dairy cattle performance. The aim of this study was to identify novel single-nucleotide polymorphism sites and novel candidate genes associated with lactation traits in Chinese Holstein cows under high-temperature and humidity conditions in southern China. A genome-wide association study was performed for the lactation traits of 392 Chinese Holstein cows, using GGP Bovine 100 K SNP gene chips. Some 23 single nucleotide polymorphic loci significantly associated with lactation traits were screened. Among them, 16 were associated with milk fat rate, 7 with milk protein rate, and 3 with heat stress. A quantitative trait locus that significantly affects milk fat percentage in Chinese Holstein cows was identified within a window of approximately 0.5 Mb in the region of 0.4-0.9 Mb on autosome 14. According to Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses, ten genes (, , , , , , , , , and ) associated with lactation fat percentage, milk yield, antioxidant activity, stress resistance, and inflammation and immune response were identified as key candidates for lactation traits. The results of this study will help in the development of an effective selection and breeding program for Chinese Holstein cows in high-temperature and humidity regions.
泌乳性状对奶牛具有重要经济意义。中国南方气候高温高湿，环境与遗传的相互作用对奶牛性能有很大影响。本研究旨在在中国南方高温高湿条件下，鉴定中国荷斯坦奶牛泌乳性状相关的新单核苷酸多态性位点和新候选基因。利用GGP牛100K SNP基因芯片，对392头中国荷斯坦奶牛的泌乳性状进行了全基因组关联研究。筛选出约23个与泌乳性状显著相关的单核苷酸多态性位点。其中，16个与乳脂率相关，7个与乳蛋白率相关，3个与热应激相关。在常染色体14上0.4 - 0.9 Mb区域约0.5 Mb的窗口内，鉴定出一个显著影响中国荷斯坦奶牛乳脂率的数量性状位点。根据基因本体论和京都基因与基因组百科全书分析，确定了10个与泌乳脂肪率、产奶量、抗氧化活性、抗逆性以及炎症和免疫反应相关的基因（、、、、、、、、和）作为泌乳性状的关键候选基因。本研究结果将有助于为高温高湿地区的中国荷斯坦奶牛制定有效的选育方案。
