MELANOCORTIN RECEPTOR MC4R GENE AND ITS RELATIONSHIP WITH LIFE EXPANSION, BREEDING PERFORMANCE, AND REPRODUCTIVE QUALITIES IN FRENCH GREAT WHITE SOWS BREED

The work aimed to investigate the life expectancy and breeding use, as well as reproductive qualities of sows of the large white breed of French selection of different genotypes for the MC4R melanocortin receptor gene. The selection of samples of biomaterial and the study of the indicated groups of quantitative traits were carried out in the conditions of the breed breeder for breeding large white pigs of the State Enterprise "Experimental Farm of the Institute of Agriculture of the Northeast" of the National Academy of Sciences, the genetics laboratory of the Institute of Pig Breeding and APP of the National Academy of Sciences, as well as the Animal Husbandry Laboratory of the State University "Institute of Grain Crops" NAAS." The work was carried out following the program of scientific research of the National Academy of Agrarian Sciences of Ukraine No. 31, "Genetic improvement of agricultural animals, their reproduction and preservation of biodiversity" ("Genetics, preservation, and reproduction of biological resources in animal husbandry"). A comprehensive assessment of sows was carried out taking into account the following characteristics: life expectancy, months; duration of tribal use, months; received farts; all piglets were born, goal; all live piglets were born, goal; multifertility, ch.; nest weight at the time of weaning at the age of 30 days, kg; preservation, %. The selection index of reproductive qualities of the sow (SIRQS) was calculated according to the method of O. M. Tsereniuk et al. (2010). DNA typing of sows was performed according to generally accepted procedures. It was established that the sows of the controlled population are characterized by high indicators of long-term adaptation (the life span is 37.6±1.20 months (Сv=28.08%), the duration of breeding use is 28.4±1.11 months (Сv=34.50 %), and according to the indicators of reproductive qualities, they meet the minimum requirements of class I and the "elite" class. A significant difference between sows of different genotypes for the gene of the melanocortin receptor MC4R (MC4RAG compared to MC4RGG and MC4RAА) was established in terms of life span (6.1 and 5.4 months), according to the indicators of "multifertility, goal" (0.9 and 0.6 goals), "nest weight at the time of weaning at the age of 30 days, kg" (5.6 and 4.5 kg), "nest weight at the time weaning at the age of 60 days" (14.0 and 11.3 kg). The coefficient of variability (Сv, %) of life expectancy, duration of breeding use, and absolute indicators of reproductive qualities in sows of different genotypes for the melanocortin receptor gene MC4R range from 4.59 to 42.57%.Reliable correlations in sows I, II, and III were established between the following pairs of traits: SIRQS × multifertility (I subexperimental group +0.958±0.0641; II – +0.962±0.0683; ІІІ – +0.989±0.0250), SIRQS × weight of the nest at the time of weaning at the age of 30 days, multifertility (I sub-experimental group +0.848±0.1185; ІІ – +0.940±0.0853; ІІІ – +0.904±0.0723 ). The maximum increase in additional production was obtained from sows of the 1st experimental group and the 1st experimental group (МС4РАА). It is +5.91%, and its value is +226.80 UAH/head/farrowing.