GENOTYPING OF BETA-LACTOGLOBULIN GENE IN DIFFERENT BREEDS OF CATTLE IN SLOVAKIA

There is generally an agreement in the literature that genetic variant s of beta-lactoglobulin are associated with lactation performance and have a major influence on the composition of milk and on its manufactu ring properties, including cheese yield. The BB genotype is associated with higher fat and casein content and is more desirable for cheese m aking. The frequencies of beta-lactoglobulin alleles of the following breeds of cattle were determined in our work: Holstein Friesian, Black and White (German type), Simmental and Pinzgau breed. Analyses were a ccomplished from the DNA of blood or hair root samples by methodology based on polymerase chain reaction (PCR). Time required for PCR analys is was substantially decreased in our analyses and the changes did not have any effect on the quality of obtained PCR products. The frequenc ies of B allele were 74% in the case of Holstein Friesian cattle (n = 50), 64% in Black and White (German type) cattle (n = 37), 62% in the case of Simmental breed (n = 33) and 77% in the case of Pinzgau breed (n = 117). In order to increase the occurrence of B allele, genotyping of bovine genotypes of beta-lactoglobulin should continue, especially in the case of the animals involved in the breeding programmes in Slo vakia.