Lack of association of bovine MHC class I alleles with carcass and reproductive traits.

The present study was carried out to examine whether a relationship between bovine major histocompatibility complex (BoLA) class I alleles and carcass traits or reproductive performance exists in Braunvieh and Fleckvieh AI (artificial insemination) bulls. The influence of BoLA class I (BoLA-A) alleles on deregressed breeding values for net growth rate, carcass index and thigh volume was assessed in Braunvieh crosses and Fleckvieh bulls with a gene substitution model. The reproductive traits: non-return rate and interval between first and last insemination of daughters (female fertility), as well as non-return rate of inseminated cows (male fertility), were only investigated in Fleckvieh animals. No influence of the BoLA-A region on the traits evaluated could be demonstrated. An improper, i.e. less restrictive analysis would have led to spurious results.