Influence of paratypical factors on productive qualities of Holstein cows

Abstract

The problems of adaptation of a highly productive Holstein breed to new natural and climatic conditions and using their productive qualities are relevant. In order to study the influence of paratypical factors on the productive characteristics of Holstein cows, productive qualities of Holstein cows and their paternal half-sisters brought from the USA were compared. It has been established that during their first, second and third lactation periods, Holstein cows had better milk yield parameters than their paternal half-sisters brought from the USA. In Holstein cows, values of repeatability and heritability of milk yield parameters were higher than in their half-sisters. The influence of the “Region of reproduction” factor was observed for the milk yield per lactation. To the least extent, it was observed for the mass fraction of protein. The highest frequency, heritability, and factoriality of milk yield parameters were observed in Pilot’s daughters.