The influence of biotic factors on the parameters of the nucleolus

Abstract

Relevance. The nucleolus regulates many aspects of cell physiology, including genome organization, stress response, aging, and lifespan. The number of visible nucleoli per cell varies depending on the cell cycle, cellular activity, or differentiation status. The aim of the study was to study the influence of abiotic factors on the parameters of animal nucleoli depending on their species (genus Ovis and genus Capra) and type of crossing (interspecific hybrids). Materials and methods. The studies were carried out at the Federal Research Center for Animal Husbandry named after Academy Member L. K. Ernst. The object of the study were domestic sheep (Romanov breed) and its hybrids (½ Romanov sheep x ½ mouflon), as well as goats of the Karachay breed and their hybrids (¾ Karachay goat x ¼ caucasian tur). The material of the study was preparations obtained from venous blood and prepared according to the Havell – Blake method. For microscopy and visualization of preparations, a “Nikon Eclipse Ni” microscope equipped with a “DS-Qi2” digital video camera was used. The processing of photo- and videomaterials was carried out using the “NIS-Elements BR4.30” and “Image Scope 1.0” software. Results. It has been established that in interspecific hybrids of goats (¾ Karachai goat x ¼ caucasian tur) the number of nucleolar-organizing regions (NOR) is 17 % more than in purebred individuals, while individual of interspecific hybrids of sheep (½ Romanov sheep x ½ mouflon) exceeded their purebred counterparts in this indicator by 47 %. The kurtosis and asymmetry of NOR in the population of purebred goats and their hybrids with the caucasian tur have the same directions. The results of the analysis of variance indicate that the effect of species on the size of the nucleoli in the studied populations is not statistically significant. The average value of the nucleolus diameter in representatives of the genus Capra was 6.17 ± 0.45 μm, genus Ovis – 6.63 ± 0.32 μm.