Genotyping of kappa casein in crossbred cattle as a factor in managing the technological qualities of milk

Abstract

The article presents the results of a study of DNA isolated from the sperm of bulls-producers of the Belgian white-blue breed, images of the wool of cattle of the Holstein breed and crossbred calves obtained by crossing Holstins with the Belgian white-blue breed, for the presence of the B-allele gene kappa casein (CSN3) associated with a high content of protein in milk and optimal coagulation properties of milk used to produce cheese and cottage cheese. It was found that out of 33 animals studied, 26 individuals (78.9%) showed the AA genotype, which determines the inheritance of the ability of animals to produce milk suitable for drinking only, 7 individuals (21.2%) have the AB genotype. Animals with the AB genotype may produce milk suitable for the production of fermented milk products, but their quality will not be high enough. Therefore, calves and gobies with the AB genotype must be crossed with individuals having the AB genotype, then it is possible to obtain offspring with the BB genotype of milk kappa casein, which can be used to make high-quality cottage cheese, yogurt, cheese and other dairy products with a high protein content. Milk of cows with the genotype BB has the best technological qualities and does not require the addition of rennet enzyme in the production of lactic-acid products.