THE CORRELATIVE VARIABILITY OF THE FINAL SCORE BY LINEAR CLASSIFICATION AND LIFETIME PRODUCTIVITY INDICATORS AMONG BLACK-AND-WHITE DAIRY COWS OF DIFFERENT BREEDS

Abstract

A study on the correlative variability of the final score by linear classification and lifetime productivity indicators of Black-and-White Dairy cows of different breeds was conducted in the herd of the private enterprise "Burynske" in the Podlisniv branch of the Stepaniv territorial community. Foreign studies on the cows evaluation of different breeds by conformation type using the linear classification method were analyzed, which proved that the lifetime productivity indicators of animals depend on many genotypic and paratypic factors. In this direction, the existence of significant moderate and close positive correlations between the majority of linear traits and functional life of cows in the herd was established. It has also been proven that the final score level of cows by type is closely correlated with descriptive traits that significantly affect lifetime productivity indicators. According to the results of our own research, it was found that degree of the final score of first-born cows for the conformation type directly determines the variability level of indicators to the duration of use and lifetime productivity within both experimental breeds. Cows of the Holstein and Ukrainian Black-and-White dairy breeds with a rating of "very good" exceeded animals with ratings of "good plus" and "good" by indicators of duration productive use and milk productivity throughout life. Holstein cows rated "very good" were better than animals rated "good plus" and "good" in terms of lifetime milk yield and milk fat yield, respectively by 4589 and 21653 kg, and 191 and 918 kg. The final score, in the presence of a correlation with lifetime productivity indicators, can serve as a predictor of longevity, which will allow effective selection of first-born dairy cows based on the results of a linear evaluation in the first months of lactation.