Reproductive qualities and the level of their phenotypical consolidation in sows of different operational value

The results of studies of indicators of reproductive qualities of sows of different operational value, the level of their phenotypic consolidation are presented, and the economic efficiency of using sows in experimental groups is calculated. The experimental part of the research was carried out in LLC "Druzhba-Kaznacheevka" in the Dnepropetrovsk region and in the laboratory animal husbandry of the State Institution "Institute of Grain Crops of the NAAS of Ukraine". The work was carried out according to the program of scientific research of NAAS No. 31 "Genetic improvement of farm animals, their reproduction and preservation of biodiversity (Genetics, conservation and reproduction of biological resources in animal husbandry)" task "To determine the adaptive characteristics and the nature of inheritance of polygenic-hereditary traits of pigs of different genotypes and to develop an integrated system for creating a highly productive population". The object of research was sows of the Llarge White breed. It was found that the sows of the main herd, according to the characteristics of reproductive ability, belong to the I class and the elite class. The number of sows from which 100 or more live piglets were obtained during the breeding period is 27.45 %. Sows in the "high operational value" category exceed their peers in the "average operational value" category in terms of life expectancy and breeding use by 25.1 and 26.2 months respectively. A significant difference between the animals of the indicated groups was established according to the indicators "received farrowings", "received live pigs in total, head", "multiple births, head.", "weight of the nest at the time of weaning at the age of 28 days, kg" and the index of N. D. Berezovsky. The coefficients of phenotypic consolidation (К1, К2) range from – 0.050 to +0.231 units, which indicates an insufficient level of consolidation of reproductive qualities in sows of the controlled population and determines the vector of further work of agricultural specialists and research workers - curator of work in this direction. The coefficient of pair correlation between the breeding index of sow reproductive qualities (SIRQS) and the absolute indicators of reproductive qualities of sows of different operational value ranges from –0.525 (tr = 3.09) to +0.934 (tr = 81.8). The maximum increase in additional production was obtained from sows of the "high operational value" category – + 3.41 %, and its cost is 92.44 UAH /heard/ farrowing. Key words: sow, breed, reproductive qualities, operational value, coefficient of phenotypic consolidation, cost of additional production, variability, correlation.