Vol 143, No 5 (2023)

The importance of vitamin D3 for maintaining the level of health in conditions of acute respiratory and vascular infectious pathology COVID-19 is considered. Physiological vitamin deficiency has been documented as a negative predictor of virus exposure and disease severity. A complex of clinical and experimental studies documents that vitamin D3 performs the function of controlling hemovascular homeostasis – the endothelium of the vascular wall, a complex of immunological reactions, coagulation and rheological properties of blood, systemic hemodynamics, etc. The variety of effects is determined by the transcriptional role of the vitamin D3 receptor, which expresses gene targets for synthesis functional protective proteins. The possibilities of supplementation, maintaining the level of vitamin D3 and its chemical metabolites, for the preventive and therapeutic strategy of COVID-19 are considered.

Modern approaches to the organization of hunting are based on the principles of sustainable development, requiring a combination of biodiversity conservation and economic efficiency, which is impossible without improving the accuracy and objectivity of data on the number of hunting animals. The proposed review article discusses various types and methods of accounting for hunting animals: winter route accounting, questionnaire and expert methods, run-through accounting, air accounting, salary and tape accounting. At the same time, the main emphasis is placed on the analysis of winter route accounting of animals as the main method for estimating the number of most hunting animals in the Russian Federation. As a possible complement or an independent alternative to accounting for the number of hunting animals, the prospects for the use of aerial accounting using unmanned aerial vehicles are considered.

The effect of organic forms of silicon contained in plant tissues on the digestibility of feed for herbivorous mammals has been studied. In the process of digestion, an extremely small part of the consumed silicon is assimilated, which makes it possible to use organic silicon naturally contained in plants as an indicator of the digestibility of plant foods. The consumed silicon reduces the digestibility of the feed, puts a limit on the fermentation of the consumed vegetable substrate and its structural components (fiber, lignin). With an increase in the part of silicon in the consumed vegetation per unit, the digestibility decreases linearly by 3–4 units. The fermentation limit is set when the silicon content in the feed is within 3–4% of the dry weight. Among the main groups of forage plants (grasses and forbs), the amount of silicon is significantly higher in grasses (1.70 and 0.91%, respectively). For this reason, the digestibility of grasses in all compared animals (camels, Przewalski’s horses, bison, saiga) is 1.2–1.4 times lower than the digestibility of forbs. With an increase in the proportion of grasses in feed per unit, the digestibility of feed in animals with different types of digestion (ruminant, monogastric) decreases linearly by an average of 0.16 units. The different digestibility of grasses and forbs causes the separation of herbivores by types of nutrition and food specialization. Consumers of various forbs (saigas) avoid the consumption of grasses and are not viable with their dominance in pasture vegetation. The specific features of the digestion of herbivores (Equidae, Bovidae) provide an increased volume of consumption, compensating for the reduced digestibility of grasses.

As a result of agrobacterium-mediated transformation the rolA, rolB, rolC, and rolD genes of Agrobacterium rhizogenes are integrated into plant genomes as part of T-DNA. These genes cause abundant growth of hairy roots, and the regeneration of shoots from them causes short stature, shortening of internodes and wrinkled leaves. A sufficient number of representatives of the genera Nicotiana, Linaria, Ipomoea and others in their genome contain some rol genes that got into them during horizontal gene transfer and thus evolutionarily fixed. The conservatism of the rol genes of A. rhizogenes in naturally transgenic plants can probably be associated with the performance of important biological functions by them. The purpose of this review article is to review the currently available data on the biological role of rol genes in hairy roots, transformed plants, and naturally transgenic plants. The results of scientific studies published to date describe the expression of rol genes both together and separately. It should be noted that expression has a different effect on the morphology of both plants transformed by agrobacteria and naturally transgenic species. The review presents the results of studies that have shown a positive effect of rol genes on secondary metabolism, the antioxidant system and plant stress resistance. The question of the possible effect of protein products of rol genes through the influence on the content of phytohormones or sensitivity to them is also discussed. Experimental evidence of subcellular localization of Rol proteins and enzymatic activity of Rol proteins with respect to phytohormone glucosides are described. However, these experiments did not give exhaustive answers, and therefore studies of the biological functions of the rol genes should be continued. This knowledge can be used to create transgenic and genome-edited plants that have economically valuable traits.

The results of the study of Lake Tolpanjärvi’s ecosystem are reported. Its hydrological and geochemical indices, as well as the current condition of biotic communities (zooplankton, benthos and fish population), were studied and analyzed. Analysis of the chemical composition of water indicates the low organic matter content (total phosphorus 0.007 mg/l, nitrogen 0.26 mg/l) of the lake. The Tolpanjärvi is an oligotrophic lake, as indicated by the abundance of zooplankton (with a biomass of less than 1 g/m³) and zoobenthos (biomass 0.44 g/m²). The lake is of an oligosaprobic class (2nd quality class, clean natural water), as evidenced by its saprobity index estimated using Pantle–Bukk’s method. The quantitative indices of zoobenthos varied from 120 individuals/m² and 0.08 g/m² in the profundal zone to 1200 inds./м² and 0.86 g/m² in the quiet littoral zone. The lake is more similar in the chironomid index (К – 2.00) to clean natural water. It is inhabited by 8 fish species of 5 families. The fish population is dominated by the whitefish Coregonus lavaretus, the perch Perca fluviatilis and the roach Rutilus rutilus. Two ecological forms of whitefish, differing in both the number of gill rakers (sparsely-rakered 18–24 and medium-rakered 28–36) and biological indices (linear-weight growth рост, maturation, fertility and feeding), occur in the lake. Stable highly diverse ecosystems were shown to form the basis for the preservation of the gene pool and for assessment of the current condition of water bodies heavily affected by human activities.