Zhang Xiaoxue, Wang Dan, Zhang Menghua, Xu Lei, Huang Xixia, Wang Yachun
College of Animal Science, Xinjiang Agricultural University, Urumqi 830052, China.
Key Laboratory of Animal Genetics, Breeding and Reproduction of Ministry of Agriculture and Rural Affairs, National Engineering Laboratory of Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China.
Animals (Basel). 2025 Jul 3;15(13):1960. doi: 10.3390/ani15131960.
Genomic selection (GS) is a new landmark method in modern animal breeding programs, and it has become a tool for routine genetic evaluation regarding dual-purpose cattle breeding. In this study, we employed data on milk-production, reproduction, and growth measurements of dual-purpose Simmental cows during the period 1987-2022 from two large-scale farms in Northwest China. For this purpose, we used a single-trait model based on the A-array PBLUP and H-array ssGBLUP to perform genetic evaluation of milk-production, reproduction, and growth traits by applying the restricted maximum likelihood (REML) methods. The results revealed that the heritability based on the additive genetic correlation matrix was approximately 0.09-0.31 for milk-production traits, 0.03-0.43 for reproduction traits, and 0.13-0.43 for growth traits. In addition, the heritability based on the genome-pedigree association matrix was similarly 0.09-0.32 for milk-production traits, 0.04-0.44 for reproductive traits, and 0.14-0.43 for growth traits. In the entire population, the reliability of genomic estimated breeding values (GEBVs) increased by 0.6-3.2%, 0.2-2.4%, and 0.5-1.5% for milk-production, reproductive traits, and growth traits, respectively. In the genotyped population, the reliability of GEBV for milk-production and reproduction traits increased by 1.6-4.0% and 0.4-3.6%, respectively, whereas the reliability of GEBV for growth traits decreased by 12.0-17.0%. These results suggest that the construction of an H-matrix with ssGBLUP could improve the heritability and reliability of breeding values for milk-production and reproduction traits. However, the advantage was not evident for growth traits in smaller populations. The present results thus provide a basis for future application of genomic genetic evaluation of dual-purpose Simmental cattle, providing data support for the selection and marketing of excellent breeding bulls, thereby helping to establish a basis for their independently bred breeding bull.
基因组选择（GS）是现代动物育种计划中的一种新的标志性方法，它已成为兼用型牛育种常规遗传评估的工具。在本研究中，我们使用了来自中国西北两个大型农场1987 - 2022年期间兼用型西门塔尔奶牛的产奶、繁殖和生长测量数据。为此，我们使用基于A阵PBLUP和H阵ssGBLUP的单性状模型，通过应用限制最大似然（REML）方法对产奶、繁殖和生长性状进行遗传评估。结果表明，基于加性遗传相关矩阵的遗传力，产奶性状约为0.09 - 0.31，繁殖性状为0.03 - 0.43，生长性状为0.13 - 0.43。此外，基于基因组 - 系谱关联矩阵的遗传力，产奶性状同样为0.09 - 0.32，繁殖性状为0.04 - 0.44，生长性状为0.14 - 0.43。在整个群体中，基因组估计育种值（GEBV）的可靠性，产奶、繁殖和生长性状分别提高了0.6% - 3.2%、0.2% - 2.4%和0.5% - 1.5%。在基因分型群体中，产奶和繁殖性状的GEBV可靠性分别提高了1.6% - 4.0%和0.4% - 3.6%，而生长性状的GEBV可靠性下降了12.0% - 17.0%。这些结果表明，用ssGBLUP构建H矩阵可以提高产奶和繁殖性状育种值的遗传力和可靠性。然而，在较小群体中，这种优势在生长性状上并不明显。因此，本研究结果为兼用型西门塔尔牛基因组遗传评估的未来应用提供了依据，为优秀种公牛的选育和销售提供了数据支持，从而有助于建立自主培育种公牛的基础。
