Effects of the c.8514C>T polymorphism in the osteopontin gene (OPN) on milk production, milk composition and disease susceptibility in Holstein-Friesian cattle

Studies into the polymorphism of the bovine osteopontin (OPN) gene have so far been focussed on the association between milk production and milk composition, lactation persistency and the rate of growth and weight gain in young cattle. Results obtained by some authors have shown different associations for various milk parameters. Even though osteopontin is an essential component of immunological response, the relationship between the polymorphism of the osteopontin gene and the incidence of diseases in cows has not been researched as yet. The purpose of this study was to analyse the c.8514 C>T polymorphism and its association with milk parameters such as: average daily yield, average protein and fat percentage and average somatic cell count in Holstein-Friesian cattle. The study also included an analysis of the impact of polymorphism on the incidence of the most frequent cattle diseases such as: clinical mastitis (CM), ovarian cysts (OC), clinical hypocalcaemia (CH) and pyometra (P). The study population of cows was found to have two alleles in the analysed locus of the osteopontin gene: C (0.529) and T (0.471), and three genotypes: CC, CT and TT (0.288, 0.482 and 0.230, respectively). Although the study showed no significant association between the polymorphism of the OPN gene and the incidence of diseases or milk parameters, it is an important contribution to research aimed at identifying the most essential SNPs which could be used for marker-assisted selection in dairy cattle herds.HighlightsThe study population was found to have two alleles in the locus of the osteopontin gene (c.8514C>T ): C and T, and three genotypes: CC, CT and TT.CT was the most frequent genotype of the osteopontin gene (c.8514C>T ), identified in about 48% of the study population of cows.No significant differences were focused between the genotypes in the c.8514C>T locus and the milk parameters and the incidence of cattle diseases.