Some mathematical models of evaluation indices and their use in pig breeding: emphasis on the mechanism of selection of highly productive animals based on reproductive qualities

The paper presents the results of a study of the reproductive qualities of sows of the Large White breed of French selection, assessed following the requirements of the Instructions for the grading of pigs, as well as some evaluation indices based on the results of the research, the criteria for selecting highly productive animals and the economic efficiency of their use were determined. The study was conducted in the conditions of a breeding reproducer for breeding pigs of the Large White breed of the research farm and the laboratory of animal husbandry and feed production of the Institute of Agriculture of the North-East of the NAAS. The work was carried out following the scientific research program of the National Academy of Agrarian Sciences of Ukraine No. 30, “System of organizational and technological solutions for the adaptation of animals to climate change during the production of livestock products” (“Climatically adaptive and organic livestock farming”). It was established that sows of the “elite” class, as well as the I experimental group of intrabreed differentiation according to the M. D. Berezovsky index and the Yu. D. index Shatalina were superior to their peers of the “extra-class” class and the III experimental group in terms of multiparity and litter weight at the time of weaning at the age of 30 days by an average of 22.08–22.67 %. The number of reliable relationships between the indicators of reproductive qualities of sows, the M. D. Berezovsky index, and the Yu. D. Shatalina index is 80.0 %. The maximum increase in additional production was obtained from sows of the elite class (+4.23 %), then I experimental group of intrabreed differentiation by the M. D. Berezovsky index (+7.43 %) and the Yu. D. Shatalina index (+7.67 %), and its value, which was obtained from one sow of the indicated groups, is equal to +136.03, +238.98 and +246.65 UAH / head. / farrowing. To create a highly productive pig population, we propose to select animals of the “elite” class in terms of multiparity and litter weight at the time of weaning, as well as individuals in which the M. D. Berezovsky index and the Y. D. Shatalina index are equal to 41.83 ± 0.162, 69.29 ± 0.330 and more points, respectively, for the leading group of sows.