Klymkovetskyi A. Relationship between early ontogenetic development and productivity of Ukrainian black-and-white dairy cows

The features of early postnatal ontogenesis of animals of the Ukrainian black-and-white dairy breed and the influence of the parameters of weight growth of heifers on the productivity of cows were studied in the dissertation. The influence of age, hematological parameters and the composition of colostral milk of mothers on the hematological parameters of newborn calves and their further growth was investigated. The effect of live weight and average daily gains of heifers of different ages on signs of cow productivity has been studied. The studies were carried out in farms with different levels of cow productivity. The effect of growth retardation of heifers in the first year of life on cow productivity was also investigated. It was determined that the age of cows does not affect the quality of colostral milk, and it is impossible to predict it by their hematological parameters due to the presence of a multidirectional correlation. There was no significant unidirectional relationship between the quantity and quality of colostral milk of the first milk yield and most of the studied hematological signs of newborn calves on the first and sixth days after drinking colostral milk. The postnatal growth of calves in length is inversely proportional to the content of total protein in the mother's colostral milk, and is directly proportional to the content of alpha and beta globulin. For six days, the content of erythrocytes, lymphocytes, Ig G1, phagocytic, bactericidal and lysozyme activity increases in the blood of newborn calves, but the content of globulin, Ig G and Ig A decreases slightly. The formation of high milk productivity of cows is facilitated by average daily gains of more than 710 g at the age of 6-12 months. Obtaining average daily gains from birth to 12 months at the level of + 0.5 S.D. ... + 1.5 S.D. relative to the average in the herd contributes to an increase in the lifelong productivity of cows.