Association of BoLA DRB3 gene polymorphisms with BoHV-1 infection and zootechnical traits

The dairy sector is one of the leading in agricultural production sectors in the world and the bovine herpesvirus 1 (BoHV-1) is an important pathogen that causes great losses in most production systems. Moreover, BoLA DRB3 immunological gene presents different alleles related to protection against many pathogens.

Serological diagnosis was carried out to determine the BoHV-1 infection and through PCR-RFLP 506 Holstein cows from several municipalities of Antioquia were genotyped for BoLA DRB3.2 gene polymorphisms.

Alleles 8, 16, 22, and 24 were the most common out of the 42 alleles found. By indirect ELISA technique, a 58.7% prevalence of BoHV-1 infection in this population was diagnosed and Odd ratios for found alleles were calculated by logistic regression; the only significant association was held for allele 37, which showed that it effects confers susceptibility to infection. On the other hand, by using generalized linear models, a significant association between BoLA DRB3.2 gene and milk and fat yield in primiparous and services per conception in multiparous was found, with the most favorable alleles being 11 and 28 in primiparous and 22 and 28 in multiparous; allele 37 was unfavorable only in primiparous.

BoLA DRB3.2 gene polymorphisms have shown high variability and significant effects on Holstein cattle and their performance in production systems in Antioquia are at both sanitary or health and productive levels.