DURABILITY AND EFFICIENCY OF LIFETIME USE OF RED-AND-WHITE DAIRY CATTLE

Abstract

The study was conducted on 325 cows of Ukrainian Red-and-White Dairy and Holstein breeds of the herd of the farm “Khristinovske”. These cows were descended from 28 bulls of 12 lines and related groups. A sufficiently high level of indicators of the duration and effectiveness of lifetime use of cows was established. The average life expectancy of the cows under control was 2750, economic use was 1711, and lactation was 1459 days. An average of 26221 kg of milk, 1097 kg of milk fat and 889 kg of protein were obtained from cows in lifetime (3.63 lactations). On average, 8.7 kg was milked per day of life from cows, on day of economic use – 14.6 kg, on day of lactation –17.2 kg. Received 657, 1030 and 122 g of milk fat and protein, respectively. On average, the coefficient of economic use rate was 58.5%, the lactation rate was 85.6%, and productive use was 49.9%. For most of the studied features of the duration and effectiveness of lifetime use, multidirectional and low interspecific differentiation were established. Holstein cows had the same cows of Ukrainian Red-and-White Dairy breeds as expectancy of life, economic use, and lactation. Cows of the Holstein breed were dominated by cows of Ukrainian Red-and-White Dairy for milk fat and protein yield for one day of life, economic use, lactation and lactation rate. In animals of Ukrainian Red-and-White Dairy breed with increasing conditional bloodiness by Holstein, duration and effectiveness of lifetime use varied curvilinearly. For the most part, the cows group with 87.5% conditional bloodiness by Holstein had the advantage. A certain level of intergroup differentiation is established by the genetic factors of cows' lineage or related group and father parentage. For the most signes of duration and effectiveness of lifetime use are characterized by the better indicators animals of the P. F. A. Chief 1427381 related group and the genealogical line of R. Citation 267150, and by the worse indicators – P. Astronaut 1458744 line. In some cases, the intergroup difference reaches a significant level (up to P < 0.05). Of the half-sisters by parent groups, the daughters of Tumpi 112367468, Vize 660013269, and Roman 660886883 had the highest prevalence and effectiveness of lifetime use, and the worst were the descendants of Y. J. Gladiator 5840283 and Voron 3206. A dispersion analysis confirmed the genetic predisposition of the phenotypic variability of the studied traits of the duration and effectiveness of economic use of cows. On average, by all counted signs, linear membership determines 6.0% of the total phenotypic variability, and parentage from father – 12.1%. Therefore, when selecting the sires, their linear identity should be taken into account with the unconditional priority of the breeding value of the bulls according to the complex breeding index.