Genetic characteristics of Poltavske sriblo rabbits by myostatin and progesterone receptor gene and selection indices

Background. Rabbit breeding is a branch of animal husbandry that produces cheap and high-quality meat products in a short period of time. Productive, maternal, reproductive and technological characteristics determine the economic efficiency of rabbit breeding under the conditions of full realization of the genetic potential of animals and a good fodder base. The main factor in the development of rabbit breeding is the increase in the number of animals, which is supported by improved maintenance, veterinary support and breeding practices. Materials and Methods. The experiment was conducted on a population of rabbits (200 heads) of the Poltavske sriblo breed. After weaning at 45 days of age, the young were separated by sex and kept 3–4 animals in a cage. 3-month-old males were placed in individual cages until they reached the age of breeding use – 150–160 days. Rabbits were fed granulated compound feed: concentrated fodder, grass meal, feed additives of animal origin, minerals and premixes. Blood was taken from the ear vein. DNA was isolated using a standard commercial kit “DNA-sorb B” with some modifications. Wright’s F-statistic, including several F-coefficients of inbreeding, was used to assess the genetic differentiation of populations. Testing of the population according to the studied genes for Hardy–Weinberg genetic equilibrium was carried out using the Pearson χ2 test. To determine Poltavske sriblo rabbits’ breeding value, indices were calculated based on economic and beneficial traits, including genetic and economic values of individual traits. As a genetic parameter, the heredity coefficient of rabbits was used, and the economic one was the cost of the products produced. Results. The results of the peculiarities of Poltavske sriblo rabbits genetic structure analysis by the distribution of allelic variants of the myostatin gene and progesterone receptor in the context of genealogical lines are presented. It was found that the grea­test frequency of the C allele by the myostatin gene was in the descendants of the male Cooper (0.551). The frequency of the T allele in this sample of animals was 0.449, respectively. For Snowball’s line rabbits, higher values of the G allele by progesterone receptor gene (0.488) were noted due to the advantage of homozygous animals. The highest value of the effective number of alleles by the myostatin gene was characteristic of Cooper’s rabbit line (0.500), and the lowest – of Bach’s lines (0.215) and Barry’s lines (0.230). According to the progesterone receptor gene, the highest values of Ne were for the Cooper (0.500), Snowball (0.507), and Mini (0.511) rabbits, and the lowest values were for Fox (0.307). The influence of the rabbit genotype on the manifestation of economic and beneficial traits – average daily growth and fertility – has also been established. The use of the breeding value evaluation of the Poltavske sriblo breed rabbits according to the selection and genetic index according to the productivity of daughters, made it possible to single out the main males among the group, as fertilizers. Male fertilizers included Snowball, Long, and Mini. Conclusions. The obtained data can be used for selective and breeding practices in rabbit breeding with the aim of selecting breeders for the improvement of the meat productivity and reproductive ability of rabbits.