Grigoletto Laís, Santana Miguel Henrique Almeida, Bressan Fabiana Fernandes, Eler Joanir Pereira, Nogueira Marcelo Fábio Gouveia, Kadarmideen Haja N, Baruselli Pietro Sampaio, Ferraz José Bento Sterman, Brito Luiz F
Department of Animal Sciences, Purdue University, West Lafayette, IN 47907, USA.
Department of Veterinary Medicine, College of Animal Science and Food Engineering, University of São Paulo, Pirassununga, 13635-900 São Paulo, Brazil.
Animals (Basel). 2020 Jul 13;10(7):1185. doi: 10.3390/ani10071185.
Reproductive efficiency plays a major role in the long-term sustainability of livestock industries and can be improved through genetic and genomic selection. This study aimed to estimate genetic parameters (heritability and genetic correlation) and identify genomic regions and candidate genes associated with anti-Müllerian hormone levels (AMH) and antral follicle populations measured after estrous synchronization (AFP) in Nellore cattle. The datasets included phenotypic records for 1099 and 289 Nellore females for AFP and AMH, respectively, high-density single nucleotide polymorphism (SNP) genotypes for 944 animals, and 4129 individuals in the pedigree. The heritability estimates for AMH and AFP were 0.28 ± 0.07 and 0.30 ± 0.09, and the traits were highly and positively genetically correlated ( = 0.81 ± 0.02). These findings indicated that these traits can be improved through selective breeding, and substantial indirect genetic gains are expected by selecting for only one of the two traits. A total of 31 genomic regions were shown to be associated with AMH or AFP, and two genomic regions located on BTA1 (64.9-65.0 Mb and 109.1-109.2 Mb) overlapped between the traits. Various candidate genes were identified to be potentially linked to important biological processes such as ovulation, tissue remodeling, and the immune system. Our findings support the use of AMH and AFP as indicator traits to genetically improve fertility rates in Nellore cattle and identify better oocyte donors.
繁殖效率在畜牧业的长期可持续发展中起着重要作用，并且可以通过遗传和基因组选择来提高。本研究旨在估计遗传参数（遗传力和遗传相关性），并确定与内洛尔牛发情同步后测量的抗缪勒氏管激素水平（AMH）和窦卵泡数量（AFP）相关的基因组区域和候选基因。数据集分别包括1099头和289头内洛尔母牛的AFP和AMH的表型记录、944头动物的高密度单核苷酸多态性（SNP）基因型以及系谱中的4129个个体。AMH和AFP的遗传力估计值分别为0.28±0.07和0.30±0.09，且这两个性状在遗传上高度正相关（ = 0.81±0.02）。这些发现表明，这些性状可以通过选择性育种得到改善，并且仅选择这两个性状中的一个有望获得显著的间接遗传增益。总共31个基因组区域被证明与AMH或AFP相关，并且位于BTA1上的两个基因组区域（64.9 - 65.0 Mb和109.1 - 109.2 Mb）在这两个性状之间重叠。鉴定出各种候选基因可能与排卵、组织重塑和免疫系统等重要生物学过程相关。我们的研究结果支持将AMH和AFP用作指示性状，以通过遗传方式提高内洛尔牛的繁殖率并识别更好的卵母细胞供体。
