Indexes of reproductive ability and their repeatability in sows of different genotypes, taking into account the polymorphism g.1426g> a of the Mc4r gene

Abstract

The results of studies of the reproductive ability of sows of different genotypes are given taking into account the polymorphism g.1426G> A of the MC4R gene, the factor of repeatability of characters is determined, and the economic efficiency of the research results is calculated. The experimental part of the research was carried out in the conditions of the «Druzhba-Kaznacheevka» LTD in Dnipropetrovsk region. The objects of research were sows of the Large White breed. It was determined that sows of the main herd, according to signs of reproductive ability, belong to class I and class elite. The experiment showed that sows of genotype AG exceeded their peers of others (GG and AA) in terms of “born piglets total, heads” by 1.6 and 0.7 heads, “Live piglets born (multiple births), heads - by 1 6 and 0.9 heads, “the mass of the litter at the time of birth, kg” - by 2.7 - 1.3 kg., “the mass of the litter at the time of weaning at the age of 28-35 days, kg” - by 5, 1 - 3.9 kg. The difference between animals of the indicated genotypes is: for large-foetus - 0.06-0.01 kg, the index "evenness of the sow’s litter in live weight of piglets at birth, points" - 1.05-1.84 points, index of N. D. Berezovsky - 3.75 -2.36 points. The index of the safety of piglets before weaning ranged from 84.4 to 93.0 %. It was proved that the minimum value of the index “evenness of the sow’s littar in live weight of piglets at the time of birth, points (7.76 ± 1,082 points) are characterized by sows of genotype AA, in which the rate of multiple pregnancy ranged from 8 to 14 pigs, and the value of the sign“ large-foetus, kg "equaled 1.37 kg. The repeatability coefficient for sows of the main herd and sows of the Large White breed of different genotypes for the melanocortin 4 (MC4R) receptor gene ranges from -0.916 ± 0.1418 (І-IV farrow, genotype - GG, sign - “piglet safety before weaning, %) to 0.978 ± 0.0738 (I-V farrow, genotype - GG, sign - “large foetus”, kg ”). The maximum value of the phenotypic consolidation coefficient was found in sows of genotype AA according to the following quantitative characteristics: “live piglets (multiple births), heads.”, “litter weight at the time of birth, kg”, “litter weight at weaning age of 28-35 days, kg "," the safety of piglets before weaning ,% ". The sows of the genotype GG belong to the unconsolidated group according to the signs of reproductive qualities. The use of sows of the genotype for the melanocortin 4 (MC4R) AG receptor gene provides additional products at the level of 5.15 %, and its cost is 165.41 UAH /head. Keywords: sow, breed, reproductive ability, MC4R gene, genotypic consolidation coefficient, variability, correlation, repeatability.