GENETIC AND POPULATION PARAMETERS OF UKRAINIAN RED DAIRY COWS DEPENDING ON CONDITIONAL BREEDING BY HOLSTINA BREED

Abstract

A significant level of intergroup differentiation and specificity of cows with different proportions of conditional blood by Holstein breed on the basis of milk productivity was revealed. There is a tendency of some increase in milk yield of cows with an increase in their conditional blood content by Holstein breed over 50% and above and a decrease in milk fat content by 0.16%.
 Our research has established quite significant recurrence rates for the considered signs of milk productivity at the highest degrees of probability, which indicates the possibility of effective selection of cows on the basis of milk productivity for the first lactation. Age-related recurrence of signs of milking between the first and higher lactation is higher than the same in terms of fat content in milk. At the same time, there is a clear trend of a gradual increase in the coefficients of recurrence of both quantitative and qualitative composition of the milk of cows of the herd with an increase in their conditional blood content by Holstein breed. The only exceptions are low-blooded animals (up to 50%).
 One-factor analysis of variance revealed a very insignificant and unreliable effect of heredity by Holstein breed on the hopes of cows for both the first and higher lactation. The influence of conditional blood by Holstein breed on the variability of fat content in milk is slightly higher (11–15%) at the highest levels of reliability.
 Correlation analysis of signs of milk yield and fat content in milk for both the first and higher lactation revealed mostly low values of correlation coefficients with a predominantly low degree of reliability. There was some increase in the correlation and change of its direction from negative to positive in high-blooded Holstein animals.
 Significant variability of coefficients of phenotypic consolidation of cows of different conditional bloodlines by Holstein breed on the main signs of milk productivity is noted. There is a tendency to reduce the coefficients of phenotypic consolidation of signs of milk productivity, in addition to the fat content in milk, with an increase in conditional blood in Holstein breed to 75% and above and in low-blooded animals (up to 50%).