Clinical and biological significance of DNA markers in mastitis in cows of the Ukrainian Red Dairy breed

This is the authors' abstract. We don't add key points for this paper.

Mastitis in dairy cattle is one of the most common production-related pathologies, causing significant economic losses in the dairy industry and negatively affecting animal health and milk quality. Under modern livestock conditions, the search for DNA markers associated with resistance or susceptibility to mastitis has become particularly important. The aim of this study was to determine the clinical and biological significance of BoLA-DRB3 gene polymorphisms in Ukrainian Red dairy cattle (URD) in relation to mastitis. Genotyping of 97 animals was performed using PCR-RFLP with restriction endonucleases RsaI, HaeIII, and BstYI (XhoII). A total of 34 BoLA-DRB3.2 alleles were identified, six of which were informative. Statistical analysis revealed two alleles that met the criteria for DNA markers: BoLA-DRB3.2*26 (P < 0.01) was associated with increased susceptibility to mastitis, whereas BoLA-DRB3.2*28 (P < 0.05) was a marker of resistance. Comparative analysis with two other native breeds – Ukrainian Black-and-White Dairy (UBWD) and Ukrainian Red-and-White Dairy (URWD) – showed no direct overlap of DNA markers, except for allele BoLA-DRB3.2*22. The findings confirm that the BoLA-DRB3 polymorphism can serve as a molecular marker for assessing genetic predisposition to mastitis and for developing breeding programs. The practical significance of this study lies in the possibility of implementing genetically based preventive and therapeutic measures that will contribute to improved productivity, the preservation of herd health, and the rational utilization of domestic genetic resources.