Effect of beta-lactoglobulin genotypes on composition and technological properties of milk in Ukrainian Black-and-White dairy cattle

Abstract

A total of 200 Ukrainian Black-and-White dairy cows were genotyped for the betalactoglobulin gene (β-LGB). The β-LGB genotypes were analyzed using PCR-RFLP method. In this breed, the frequencies of alleles were follows: A=0,630 and B=0,370. The frequencies of AA, AB and BB genotypes were 0,430, 0,400 and 0,170 respectively. Results showed that β-LGB AA genotype had higher milk yield, whole protein, total solids and milk solids non-fat (MSNF) content than AB and BB individuals. With respect to milk fat content (%), the BB genotype had higher levels than the AA and AB individuals. The results showed that milk with best cheese-making properties was obtained by cows with the genotype BB. Their milk had higher casein content and casein number and shorter coagulation time. At the same time the heat stability of this milk was less compared to milk from animals with the β-LGB AA and AB genotypes. The results presented here demonstrate that the β-LGB genotypes may be used as selection criteria in programs of Ukrainian Black-and-White dairy cattle breeding and improvement.