Abstract: In recent decades, animal hybridization has been one of the central fundamental problems of evolutionary biology and zoology. The development of this area of science is associated with the practical use of the metapopulation approach to the analysis of population structure with the wide use of molecular genetics methods for research of sympatric speciations [...] Load More of animals. It makes it possible to solve not only fundamental biological problems but also significant applied problems of species conservation and biological diversity of populations. The purpose of this research was to determine intraspecific differentiation, modifications of genotypic diversity, and mammal population structure taking into account the dynamics of heterogeneous spatio-temporal distribution of the animal population in conditions of the highly fragmented environment using the example of a burrowing rodent. The object of research was the sympatry of the red-cheeked ground and spotted sousliks. The sampling size of the research was 217 individuals of both species from 10 contact settlements. The research sample of rodents was formed during the field work for the period of 2017-2019. The comparative analysis of genomes of mitochondria and nuclear DNA of animals has been performed through molecular genetics diagnostics. For the purpose of systematization of species belonging of caught and marked specimens of marmots and determination of modifications of animal hybridization, five kinds of molecular markers were used in the research: D-loop, Hoxb5, p53, ZfX, and SmcY. The method of bioacoustic monitoring of frequency and interval indicators of warning calls of the red-cheeked ground and spotted sousliks and of their natural hybrid varieties was used for analysis and revealing of parent species characters in hybrid populations. Based on the method of discriminant analysis of the set of quantitative indicators of warning calls and parameters of the calls of both investigated species of marmots and their hybrids, the genetic character of inheritance of acoustic features of parental species in interspecies hybrids of the burrowing rodent has been determined. Based on the results of discriminant analysis, generations of hybrid individuals of the red-cheeked ground and spotted sousliks were systematized by age groups. Differences in the inheritance of features of parent populations in investigated hybrid individuals have been revealed. The results obtained are of practical importance for the development of the theory of evolutionary biology. They will be useful for a better understanding of the mechanism of natural interspecific hybridization of sousliks. The results obtained can be used in planning and organizing conservation activities for this species in the territorial subjects of the region.

Keywords: population, souslik, hybrids, molecular genetics diagnostics, species belonging, acoustic features, molecular marker.

Abstract: Serotonin is of crucial importance for the animal body performing the control over important physiological functions, including ovulation, insulin secretion, as well as serotonin predetermines the specific behavioral reactions. Modern science has accumulated enough experimental material on the regulatory influence of this neurotransmitter on the activity [...] Load More of immunocompetent organs. However, data on the participation of serotonin in their structural and functional development have not yet been properly considered. The purpose of the paper was to investigate the morphogen effects of serotonin synthesis intensity on thymus development and manifestations of immune system disorders among animals. The fetuses of 38 laboratory pregnant female Wistar rats and post-natal rats living under standard conditions were used as an experimental basis for the research. The object of the research was serotonin receptors encoded with the Htr1a gene as the most represented receptor in the animal body. Isoflurane inhalation anesthesia for animals was used to obtain embryonic material. The method of a polymerase chain reaction with reverse transcription was used to detect and research the dynamics of the expression level of Htr1а receptors to serotonin in the thymus of the animals under study. Observation and analysis of isolated total RNA were carried out with the help of electrophoresis in agarose gel and the ChemiDoc MP System for gel imaging and documentation. With the use of the western blotting analytical method, proteins have been detected and transferred to the membrane. The quality of the process was controlled by coloring the hydrophobic nitrocellulose membrane with the Ponceau S dye. The functional activity of T-lymphocytes of rat fetal thymus has been assessed through activation by T-cell mitogen to proliferative immune response. The degree of maturity of T-lymphocytes has been analyzed by double marking with monoclonal antibodies to CD8b and CD4 antigens in fetuses and mature mice. The effect of serotonin on T-lymphocytes and the effect of ConA mitogen on the expression of Htr1a mRNA receptors in the thymus have been analyzed using the polymerase chain reaction method. Analytical processing of the laboratory assessment data was performed using the Statistica 7.0 software product. The assessment of the statistical significance of differences between indicator sets was implemented based on the Mann-Whitney U test. The results of the study will be useful to find the possibility of correction of immune system disorders using serotonin receptor agonists and antagonists that change the mediator level in various organs, including the brain.

Keywords: mice, serotonin, synthesis, thymus, Htr1a gene, receptors, immune system.