Genetic dissection of bull fertility in US Jersey dairy cattle

Abstract

SummaryThe service sire has been recognized as an important factor affecting herd fertility in dairy cattle. Recent studies suggest that genetic factors explain part of the difference in fertility among Holstein sires. The main objective of this study was to dissect the genetic architecture of sire fertility in US Jersey cattle. The dataset included 1.5 K Jersey bulls with sire conception rate (SCR) records and 96 K single nucleotide polymorphism (SNP) markers spanning the whole genome. The analysis included whole‐genome scans for both additive and non‐additive effects and subsequent functional enrichment analyses using KEGG Pathway, Gene Ontology (GO) and Medical Subject Headings (MeSH) databases. Ten genomic regions located on eight different chromosomes explained more than 0.5% of the additive genetic variance for SCR. These regions harbor genes, such as PKDREJ,EPB41L2,PDGFD,STX2,SLC25A20 and IP6K1, that are directly implicated in testis development and spermatogenesis, sperm motility and the acrosome reaction. In addition, the genomic scan for non‐additive effects identified two regions on BTA11 and BTA25 with marked recessive effects. These regions harbor three genes—FER1L5,CNNM4 and DNAH3—with known roles in sperm biology. Moreover, the gene‐set analysis revealed terms associated with calcium regulation and signaling, membrane fusion, sperm cell energy metabolism, GTPase activity and MAPK signaling. These gene sets are directly implicated in sperm physiology and male fertility. Overall, this integrative genomic study unravels genetic variants and pathways affecting Jersey bull fertility. These findings may contribute to the development of novel genomic strategies for improving sire fertility in Jersey cattle.

Post-Translational Protein Deimination Signatures in Serum and Serum-Extracellular Vesicles of Bos taurus Reveal Immune, Anti-Pathogenic, Anti-Viral, Metabolic and Cancer-Related Pathways for Deimination

“…Calcium signalling is linked to a wide range of physiological and pathological processes [203][204][205], is a key driver for post-translational deimination [206][207][208] and plays an important role in the regulation of EVs [11,48]. In cattle, calcium is linked to many immunological pathways including inflammatory diseases [209], virus replication [210], parasitic infection [211], wound healing [212], reproduction [213,214] and adrenal function [215]. Interestingly, calcium regulation has been shown to differ between Holstein and Jersey cows, including via serotonergic stimulation of the calcium pathway [216].…”

Genomic prediction of bull fertility in US Jersey dairy cattle

“…Gene ontology terms can be defined as groups of genes that are involved in the same biological process or molecular function. In our previous studies, using Fisher's exact test, we identified 2 GO terms, namely calcium ion binding (GO: 0005509) and pyrophosphatase activity (GO: 0016462), significantly enriched with genes associated with SCR in both Jersey and Holstein breeds (Peñagaricano et al, 2013;Rezende et al, 2018). Here, we assessed the set of SNP linked to genes in these 2 relevant GO terms.…”

“…The US dairy industry has had access to a phenotypic evaluation of dairy bull fertility called sire conception rate (SCR) that is based on a large, nationwide database of confirmed pregnancy records . Notably, there is a remarkable variation in SCR with more than 10% conception rate difference between high-fertility and low-fertility bulls (Peñagaricano et al, 2012;Rezende et al, 2018). Therefore, it is clear that service sire fertility should be considered in breeding schemes aimed to improve the reproductive efficiency of dairy herds.…”

“…Evidence is growing, however, that genetic factors explain part of the variation in Jersey sire fertility. Indeed, we recently identified individual genes and gene sets strongly associated with SCR in US Jersey bulls (Rezende et al, 2018).…”

Across‐breed validation study confirms and identifies new loci associated with sexual precocity in Brahman and Nellore cattle

“…Some fatty acids present crucial role in the maintenance of sperm integrity, sperm motility, viability and fertility in several livestock species (Van Tran, Malla, Kumar, & Tyagi, ). Rezende, Dietsch, and Peñagaricano () found some genes associated with sire conception rate that were enriched in a functional term named “Fatty acid degradation” and reported previous studies that explained the relationship between fatty acids and the ATP synthesis, promoting the sperm motility (Amaral et al, ).…”