Abstract
BACKGROUND: Water buffaloes represent a crucial genetic resource for the global dairy industry, yet enhancements in their production performance remain relatively constrained. The advent of advanced sequencing technologies, coupled with genome-wide association studies (GWASs), has significantly boosted the potential for breeding superior-quality water buffalo. METHODS: An integrated genomic analysis was performed on sequencing data from 100 water buffaloes, utilizing the high-quality UOA_WB_1 genome assembly as a reference. This study particularly emphasized reproduction-related traits, with a focus on age at first calving (AFC). RESULTS: Our analysis revealed two significant single-nucleotide polymorphisms (SNPs). Based on these genetic markers, the GRM1 gene was identified as a candidate gene. This gene shows substantial involvement in various reproduction-associated pathways, including the FOXO signaling pathway, calcium signaling pathway, and estrogen signaling pathway. CONCLUSIONS: The identification of GRM1 as a candidate gene provides a robust theoretical basis for molecular breeding strategies aimed at enhancing fertility in water buffaloes. These findings offer critical scientific support for optimizing breeding programs, thereby improving overall production efficiency.