Formation of economically useful traits in cows of ukrainian brown dairy breed of different genotypes by beta-casein

Abstract

Recently, scientists have begun to pay more attention to research on the effects of beta-casein on human health. This is due to the presence of beta-casein A1 in milk. Cow's milk is known to contain several variants of beta-casein. However, variants A1 and A2 are the most common. This mutation is a codominant factor. There is a difference in the frequency of each genotype between animals of different breeds. Animals of the Holstein breed are characterized by the predominance of the A1A1 and A1A2 genotypes.         The influence of the beta-casein genotype on the formation of economically useful traits of Ukrainian brown dairy cattle has been studied. It was found that the animals met the breed standard in almost all indicators of milk productivity. Between animals of different genotypes the difference on separate economic and useful signs is revealed. Moreover, in different periods and on different grounds, it varied greatly, but was statistically insignificant. The best lactation showed a statistically significant difference between two homozygous genotypes in favor of the A2A2 genotype. It has been proven that milk containing beta-casein A1 can contribute to the development of some human diseases. Such diseases include cardiovascular disease, type 1 diabetes, sudden infant death syndrome and various neurological disorders. Milk proteins can also be the cause of allergies. The aim of the research was to establish the influence of the genotype of kappa-casein on the economic and useful traits of animals of the Ukrainian brown dairy breed. It is proved that the formation of herds with the A2A2 genotype for beta-casein will not have a negative impact on economic and useful traits and thus ensure the preservation of the desired indicators of livestock productivity of new types of herds. The formation of herds with the A2A2 genotype for beta-casein will not have a negative significant impact on the economic and useful characteristics of animals and thus ensure the preservation of the desired productivity of livestock of new types of herds.