HIGHLY PRODUCTIVE HERDS, THEIR SIGNIFICANCE AND RATIONAL USE
Purposeful improving selection contributes to the accumulation of desirable genotypes, increasing the specific weight of highly productive individuals, however, in practical breeding the analysis of the origin of these cows’ mothers is not always confirmed by this postulate, which requires additional research. Research to determine the influence of highly productive group of animals that quantitatively allows obtaining statistically valid information and reasoned conclusions to their specific impact on the effectiveness of selection was performed using red steppe breed in the breeding reproducer of Maysky district in the Kabardino-Balkar Republic. Of 700 cows there were 89 (12.7%) animals that met the specified selection parameters including 21 (23.6%) heifers, 32 (36.0%) of the second calving and 36 (40.4%) of three calvings and older. Of 132 heifers, the specific weight of the best was 15.9; out of 157 cows of the second calving - 20.4; out of 421cows of three calvings and older - only 8.6%, which is 2 or more times lower. Both for the first and highest lactation, the mothers of highly productive cows were inferior to their daughters, regardless of age, with increasing age of the daughters, their superiority over the mothers increases. The maximum superiority was in the groups of daughters of three calvings and older - bulls Grilyazh 6977 and Torpan 2739. The best daughter heifers were obtained from three male cows Iman 314, Knor 45026 and Tibul 3728 with an average milk yield 6379,3; 6217,2 and 6208,6 kg, which is higher than the mothers’ milk yield, according to the corresponding lactation, by 2387,1; 1735,9 and 1459,5 kg. Of the second lactation - from male cows Tibul 3728-7788,7 kg; Iman 314-7386,0 kg and Torpan 2739 - 7105,2 kg. Among cows of three calvings and older are daughters of male cows Torpan 2739-8062,4 kg and Grilyazh 6977-7991 kg. The research results showed that purposeful selection of nucleus stock cows, evaluation of the offspring quality, and selection of bulls due to compatibility on the background of improved feeding helped to increase the efficiency of breeding.