Abstract: The article presents the results of research conducted in 2016-2018 on the influence of meadow clover and the use of mineral fertilizers (for two backgrounds) and other factors on the indicators of field germination and plant survival. According to the results of research on productivity of grain-forage crops, crop rotations with clover saturation of 20 and 40 % showed the highest yield of forage units in comparison with crop rotations without clover. The collection of digestible protein and metabolic energy also increased. For the collection of feed units and digestible protein, the greatest result was shown by barley in the crop rotation with 40% clover saturation: 2.1-2.3 t of digestible protein and 0.18-0.21 t of digestible protein. This is more than in the crop rotation without clover by 0.3 t K. u. and 0.03 t of digestible protein. The studied fertilizer backgrounds increased productivity of both barley and oats in crop rotations with and without clover by 0.1 - 0.2 t/ha. The productivity index in feed crop rotations is increased by using a perennial legume crop (meadow clover) and applying two backgrounds of mineral fertilizers. With a high quality of seed sown forage crops, the energy is 80-90 %, germination90-94 %, and their field indicators are significantly lower. Higher field germination was shown by oats in the crop rotation with 20% clover saturation. In this case, the lowest survival rate was observed at 66.5 - 67.8%. The use of mineral fertilizers in crop rotations and backgrounds increased field indicators. The highest indicators were observed in oats.

Keywords: meadow clover, fodder crop rotation, field germination, survival, fertilizers, feed units.

Abstract: We studied the viability of introduced deciduous woody plants at the Polar-Alpine Botanical Garden Institute. They evaluated the completeness of lignification of annual shoots, winter hardiness, the ability to preserve and restore the growth form, shoot formation ability, the presence of annual growth in height, the ability to generative development, and methods of reproduction in culture. We studied the viability of 410 specimens of deciduous plants belonging to 261 taxon of 49 genera of 24 families differing in a systematic origin, the length of stay in the introduction experiment, life form, and origin of the source material. Half of the studied samples (49.3%) are viable, winter-hardy, have high and medium shoot formation ability, maintain and restore their growth form, have reached the generative stage of ontogenesis, individual plants give self-seeding. Unviable and absolutely non-viable make up 11.2% of the samples, are characterized by low winter hardiness, do not preserve the growth form, and do not give an annual growth in height. High vitality of trees is ensured by high winter hardiness, ability to preserve life form. Shrubs are characterized by a high ability to shoot formation and restoration of life form. The viability of plants of natural origin is higher compared with samples obtained from the culture. The lowest scores for the studied traits were observed in plants grown from cuttings of both natural and cultural origin. Introducers of natural origin are more often able to reproduce in culture by self-seeding. The highest average scores evaluated the viability of the genera Betula, Alnus, Rhododendron. According to the results of assessing the decorative state, it is possible to develop a set of agrotechnical measures to increase the level of vitality of collection woody plants

Keywords: introduction, vitality, woody plants, Kola North.

Abstract: The studies were conducted on the basis of a peasant farm located in the Kuitun district of the Irkutsk region. Studies have shown that the contamination of barley crops during the tillering phase and before harvesting using different methods of sowing and when ammonium nitrate is applied locally in different doses does not have significant differences. The strip-spread method of sowing with the “Kuzbass-8.5” sowing complex increased field germination by 3-5% compared to the ordinary sowing with the “SZ-3.6” seeder. The introduction of ammonium nitrate locally in nitrogen doses of 30 and 60 kg d.v. / ha increased the productive bushiness by 0.1 - 0 2 pcs, the length of plants by 11.1 - 15.3 cm, the spike length by 0.4 - 0.6 cm, the number of spikelets in the ear by 0.7 - 1.6 pcs., spike grains per 1.0 – 1.9 pcs., weight of 1000 grains per 0.9 – 3.1 g. The introduction of ammonium nitrate at a dose of N30 kg a.a. / ha increased the yield compared to an unfertilized background by 0.40 t / ha when sowing “Kuzbass-8.5”; by 0.23 t / ha when sowing “SZ-3.6” by cultivation and by 0.28 t / ha when sowing “SZ-3.6” by discing. A nitrogen dose of 60 kg d.v. / ha provided the largest increase in yield, which is higher than 0.21 t / ha compared to N30 when sowing “Kuzbass-8.5”; by 0.27 t / ha when sowing “SZ3.6” by cultivation and by 0.30 t / ha when sowing SZ-3.6 by disking. The strip-spread method of sowing barley with the “Kuzbass-8.5” sowing complex, against the background of local nitrogen application at a dose of 30 kg d.v. / ha in the form of ammonium nitrate, with a yield of 2.66 t / ha, provided the highest net income - 9942 p. / ha and profitability level - 87%.

Keywords: spring barley, method of sowing, ammonium nitrate, weediness of crops, field germination, productivity, efficiency.

Abstract: Mutual positive effects of components on each other are revealed. The density of the herbage of the stumpless and Eastern goat in the joint agrophytocenoses (AFC) was greater than in the single-species and increased by the end of the growing season. The highest density of herbage of boneberry and Eastern goat was observed in the AFC with the placement of components with row spacing, width 45, 60 and 75 cm. In a single AFTS height awnless brome compared to its height in the joint AFTS with a milk vetch East in the end of the growing season was smaller in the variants with row spacing 15 cm by 1.0%, 30 cm – 9.0 %, 45 cm, – 12.1 %, 60 cm – 14.5 %, 75 cm – 19.7 %. Similar results were observed for bunias Oriental, the decrease amounted to: in the aisles of 15 cm by 3.3%, 30 cm – 5.8 %, 45 cm – 19.9 %, 60 cm – 18.7 %, 75 cm – 26.4 %; for the mountaineer spread: 15 cm – 15.6 %, 30 cm – 22.8 %, 45 cm – 22.9 %, 60 cm – 24.9 %, 75 cm -16.0 %. Eastern goat and Eastern sverbiga had a large height of linear growth in the joint AFC with a boneless stalk with a width of row spacing of 45, 60 and 75 cm. In all variants of the experiment (except for row spacing of 30 cm) in the first and second years of life, the boneless stalk in joint AFC with non-traditional plants had a higher percentage of leafage than in single-species crops. Eastern goat and Eastern sverbiga in the joint AFC with the stumpless stump had the highest percentage of leafiness in the second year of life in the variants of experience with row spacing of 60 and 75 cm, and the mountaineer spread out in all variants of experience, but only in the first year of life.

Keywords: eastern goatskin, eastern swerbig, mountaineer spread wide, boneless rump, symbiotic relationships, joint agrophytocenoses.

Abstract: The work provides material on the experiments performed on the experimental field of the Irkutsk Research Institute of Agriculture in 2017. The plot area is 15 m2, the repetition is six times. The placement of experience options is systematic. The seeding rate is 6 million germinating grains per 1 ha. Sowing was carried out on May 20. Harvesting grain was carried out by direct combination - on September 10 at the onset of the development phase - full ripeness. It was established that the crops cultivated in the experiment differed in the level of grain yield. Spring 2017 triticale of the “Dobroe” variety on average from foliar top-dressing on all backgrounds showed the highest yield among all crops in the experiment, against the background without fertilizers 26.5 c / ha, against the background with N45–29.2 c / ha and against the background with N45P45K45 - 28.2 kg / ha. And the average yield increase for these backgrounds was 10.45%, 29.78% and 7.66%, respectively. In “Tulunskaya 11” wheat, the yield for all backgrounds was approximately the same - about 18 kg / ha. A significant reserve for increasing crop yields, as shown by studies, is foliar dressing with macro- and microelements, which are part of the most important physiologically active substances. They increase the enzymatic activity of plants, improve their absorption of nutrients, enhance the activity of photosynthesis and assimilative activity of the whole plant. Under the influence of trace elements, plants become more resistant to adverse environmental conditions, to damage by pests and diseases. All this has a positive effect on the level of productivity and helps to improve product quality.

Keywords: foliar top-dressing, mineral nutrition, wheat, triticale, oats.

Abstract: In the seventies of the last century, in the Republic of Sakha (Yakutia), according to researchers studying potato diseases, there are no causative agents of viral diseases in the permafrost zone. In the continuation of these studies, the influence of diseases on the Rosara potato variety was studied. Four options were used in the experiment: 1) Control-without treatment; 2) Pre-planting spraying of tubers “Fitosporin-M”; 3) Spraying plants in the budding phase of the drug; 4) Spraying plants in the phase of full flowering days. Four repetition. However, surveys of potato plantings conducted later showed a high prevalence of viral diseases (90-100%), which significantly reduces their productivity, marketability and keeping quality during long winter storage. The most common diseases of potatoes caused by viruses are different types of mosaics: wrinkled, speckled and ordinary. In this regard, rural producers are faced with the problem of the need for preventive measures that contribute to the recovery of potato seed material from viral, fungal and bacterial diseases. In the conditions of the Khangalassky ulus of the Republic of Sakha (Yakutia), studies were conducted to study the effect of potato processing on the Fitosporin-M biological product on the early maturity, quality and yield of tubers. It was found that the spraying of Fitosporin-M plants during the budding period promotes the earliest tuberization of potatoes (10 days earlier than in the version without treatment), a significant increase in potato yield by an average of 3.3 t / ha compared with the control variant. Spraying potato plants during the budding phase with Fitosporin-M increases the number of healthy tubers per unit area by 35% of the control

Keywords: potato, permafrost soil, “Fitosporin-M” preparation, precocity, productivity, quality

Abstract: The effect of trace elements on the activity of oxygen and nitrogen, which are the most important participants in metabolic processes in plants, was studied. The studies were carried out by the method of thermodynamic modeling on the basis of the “Selector” software package. The method allows you to calculate a significant number of final indicators of the systems, including the Gibbs energy of the system, the chemical potentials of the components, the pH of the solution, the redox potential of the system. We calculated 10 variants of each of the systems with a gradual increase in the content of the variable component of the system to the maximum amount. We investigated the system: trace element combination - a component that characterizes the soil - water - air. Thus, the characteristics of the independent components (nitrogen and oxygen) were taken into account, taking into account all the above phases. The results obtained in the work allow us to conclude that sandy and clay soils differently affect the activity of oxygen and nitrogen. Sandy soils, due to the inertness of silica, do not affect the chemical potentials of oxygen and nitrogen. Clay soils increase oxygen activity and reduce nitrogen activity; the effect is leveled by the formation of the sparingly soluble mineral gibbsite with an increase in the content of alumina in soils. The chemical activity of oxygen increases in the presence of copper ions (+2) in sandy soils, lead ions (+2) in sandy and clay soils. Iron ions (+2) have a negative effect on the chemical activity of oxygen in both clay and sandy soils. In this case, iron ions (+2) contribute to a significant increase in nitrogen activity in sandy and clay soils. Ions of copper (+2), lead (+2), manganese (+2) reduce the chemical activity of nitrogen in sandy soils.

Keywords: physicochemical modeling, soil, trace elements, chemical potential

Abstract: Long-term studies in old-growth apple orchards on the study of physiological processes under the influence of rejuvenating pruning showed that in old plantations, whose age is 30-35 years or more, crowns have design flaws that make them unsuitable from a physiological point of view to obtain high and stable harvests. The leaves of full-grown trees acquire a xeromorphic structure, their transpiration activity decreases and photosynthesis is weakened. In this regard, the aim of the research was to study the reaction of old-growth apple trees to various degrees of anti-aging pruning and to increase the physiological activity of trees. Options: sanitary pruning (control); trimming for 3-4 year old wood; pruning for 5-6 year old wood; trimming for 7-8 year old wood. Anti-aging pruning was manifested in the activation of growth activity of shoots, which had a positive effect on the area of leaf plates. Anti-aging pruning contributed to increased transpiration intensity. In this case, the highest values of transpiration intensity were obtained in the variants with the maximum amount of removed wood. Thus, the highest intensity of leaf transpiration at the crown periphery was obtained in the version with pruning for 7-8-year-old wood - 13.29 mg / cm2 hour. Removing perennial wood in versions with antiaging pruning contributed to an increase in the photosynthetic activity of apple leaves. In these variants, the intensity of photosynthesis at the crown periphery increased by 27.8–46.4%, depending on the degree of trimming. An even more noticeable increase in the intensity of photosynthesis was observed inside the crown. The intensity of photosynthesis in the variants of anti-aging trim increased in the center of the crown by 36.8-243.6%

Keywords: orchard, apple tree, crown, anti-aging pruning, transpiration rate, photosynthesis rate.

Abstract: In the field, seedlings were exposed to natural frost - 37.5 ° C. Hybrid families: 20-11 (“Ussuri sweet” x “Henomeles Japanese”) x 20-11 (“Ussuri sweet” x “Henomeles Japanese”) -73.3% frost-resistant seedlings, “Oszi rordas” x seedling “Yakovleva 111” - 79.1 % and 24-45-45 (“Phorun” x “Olivier de Serre”) x (“Gervais” + “Olivier de Serre” + “Dekanka winter”) -84.6%, showed the greatest frost resistance in the hardened state. In laboratory conditions, the most dangerous damaging factors were modeled in an artificial climate chamber according to the second and third components of winter hardiness - maximum frost resistance in the middle of winter in the hardened state and stability of resistance to frost during the thaw. Critical temperatures affected the same seedlings, sequentially applying the specified modes - hardening, -37 ° C and hardening, thaw + 2 ° C (5 days), frost -25 ° C. In case of damage by two factors in the predominant parts of families, the yield of highly winter-resistant seedlings becomes lower compared with exposure to only low temperature. High winter hardiness in two components -the third and second, was shown by seedlings in the origin of which there is a variety with high resistance to winter damage “Phorun”. 33.3% of the descendants of the “Tonovetki” corresponding winter hardiness were identified in the family 24-45-45 (“Gervais” + “Olivier de Serre” + “Dekanka winter”) x (“Phorun” x “Olivier de Serre”), whereas in the hybrid population 17-43-30 “Shihan” x (“Phorun” - free pollination) is about 50% of highly winter-resistant seedlings, while about 5% of genotypes that survived the given regimes without damaging tissues and kidneys. Remote hybridization allows us to hope for new prospects in obtaining highly winter-resistant varieties of pears and other fruit crops.

Keywords: pear, selection, hybrid seedlings, resistance to frost, winter hardiness components

Abstract: The article provides recommendations and justifications for changes in the list of rare and endangered vascular plants to be included in the Red Book of the Irkutsk Region in its new edition. The basis of the research was the observations of the authors, the results of processing herbarium collections (IRKU), literature and Internet sources, including the Digital Herbarium of Moscow State University (MW). As a result of the data obtained, it is proposed to exclude Viburnum opulus L. and Veronica officinalis L. as species that do not need to be protected due to an increase in their numbers in the last decade and the invasive nature of existing populations. Change the rarity status of Oxytropis sylvatica (Pall.) DC.) From category “1” to “4” as more appropriate due to the unclear systematic identity of individuals of herbarium specimens and detected populations, as well as Menispermum dauricum DC. from category “2” to “5”, in connection with the restoration of numbers. Include Asplenium nesii Christ in category “0”; in the category “1” - Neottia nidus-avis (L.) Rich., Cotoneaster neopopovii Czerep., Platanthera hologlottis Maxim., Potamogeton rutilus Wolfg .; in category “2” - Astragalus rytyensisStepants., Artemisia cuspidata Krasch .; in the category “3” - Botrychium anthemoides C. Presl, Caulinia tenuissima (A. Braun ex Magnus) Tzvelev, Potentilla olchonensis Peschkova, Papaver ammophillum (Turcz.) Peschkova, Echinops latifolius Tausch; in category “4” - Cerastium maximum L. as species requiring protection, due to their limited distribution within the Irkutsk region and the high vulnerability of the identified populations.

Keywords: vascular plants, rare and protected, Red Book, Irkutsk region.

Abstract: Research covers period from 1984 to 2019. on the territory of the Omsk region in order to clarify Galliformes. The work was carried out on an area of 141.14 thousand km² in the center of the West Siberian Plain in the subzones of the southern taiga and subtaiga, in the foreststeppe and northern steppe. Common forest black grouse Lyrurus tetrix tetrix in the Omsk region: with an average annual number of 64.76 thousand individuals with a population density of 12.99 individuals / 10 km2, it occupies 35.4%, and common white-bellied capercaillie Tetrao urogallus taczanowskii according to the same indicators, respectively: 10.11 thousand, 3.19 individuals / 10 km2, - 22.5% of the territory. Eight Galliformes species / subspecies living on the territory of the Omsk Region have different dependences on solar activity (W, Wolf numbers), the period of water content and the water level in the territory. Such species of predators as the American mink, light polecat, lynx, lynx, wild boar, raccoon dog, brown bear, and corsac have different effects on chickens. They determine changes in numbers from maximum to minimum with varying population densities. The lowest indices of population size, distribution, and population density are common quail, great white partridge, and white-bellied capercaillie; gray grouse, Siberian grouse, western Siberian grouse, and forest grouse average; steppe ordinary black grouse has the highest rates. Individuals of six species / subspecies of eight serve as objects of amateur hunting, while five are rare commercially threatened.

Keywords: Galliformes, abundance and distribution, Omsk region.

Abstract: In recent years, the range of the brown bear has expanded significantly in Siberia, and its harmful value has increased. Modern features of the dynamics of the number and distribution of the bear in the Omsk region are poorly understood. In 2000–2010 the bear was counted only inthe territory of 11 taiga and subtaiga regions of the Omsk region. The average long-term number of bears in 2000–2011 amounted to 403 individuals, in 2012–2018. this figure reached 1232, and in 2019 - 2128 individuals. Animals are found in areas of the central forest-steppe, and in some hunting areas the population density of the predator reached 1.0–1.6 wasps on 10 km2. In 2014–2018 animals everywhere attacked people and livestock. The reasons for the bear population growth and the increase in its aggressiveness towards humans are similar to other regions of Siberia. The increase in numbers is due to a decrease in the hunting press, a decrease in the number of professional hunters, a loss of fear of humans, and a lack of control over the predator population. The increase in the bear population in the region was facilitated by the almost complete absence of invasive and infectious diseases in its population. Trichinosis in bears has not been observed, at least since 1998. In 1996–2018. rabies was registered in Russia in 71 710 animals belonging to 35 taxa of wild, domestic and agricultural mammals. In a brown bear, rabies was detected only three times in the Tver region, Krasnoyarsk and Primorsky territories. In the Omsk region for the period 1962–2018 rabies was recorded in 2167 individuals belonging to 18 species of mammals, but not in a bear. Dangerous growth trends and the aggressiveness of the brown bear dictate the need for strict regulation of the number of predators.

Keywords: Omsk region, brown bear, abundance, trichinosis, rabies.

Abstract: Studies were conducted to determine the dependence of the size of the fruiting body of the fungus Suillus granulatus (Fr.) O. Kuntze (grainy oiler) on the weight of its cap. Material was collected in the vicinity of the villages of Oyok and Nikolsk in the Irkutsk region of the Irkutsk region in a coniferous forest in August 2019. 450 fruit bodies were weighed with an accuracy of 0.1 g, the diameter of their caps was measured with an accuracy of 1 mm. The variation in the diameter of the caps ranged from 12 to 145 mm, their weight varied from 0.1 to 107.1 g. The largest number of mushrooms fell on the middle classes in the range from 40 to 99 mm - 328 pcs. (72.9%). The calculated average values for all classes demonstrate a direct dependence of the weight of mushrooms on size. The maximum weight gain is observed in the first stages of development, from 19 to 39 mm it is 99.2%, from 39 to 59 mm - 54.8%. With further growth of the hats, the percentage of weight gain decreases. The correlation coefficient r ± mr = 0.93 ± 0.02 indicates a close relationship between the studied values. The larger the size of the hat, the higher the weight of the fruit body of the grainy oiler. Regression analysis showed that an increase in the size of the hat by 1 mm increases the weight of the fruit body of the fungus by 0.69 g. The results of the studies allow us to use them for research using the method of calculating tape counts along the running lines for reconnaissance estimation of their yield directly in the fruiting year without laborious operation collection and weighing.

Keywords: mushrooms, Suillus granulatus (Fr.) O. Kuntze, grainy oiler, correlation coefficient, cap size, fruit body weight.

Abstract: The studies were conducted in order to identify the species composition, places of growth of ecological and resource assessment of useful plants of the Lamiaceae family in the city of Irkutsk and the Irkutsk region. The data of field work, floristic reports and published materials of specialists were used. To assess the distribution of plants used a 5-point scale of abundance. Of the 38 species of the family growing in the study area, 36 species from 19 genera are useful plants in various fields of application. There are 34 species of plants used in official, folk medicine and homeopathy, which are used as ornamental plants - 16 species that create a base for beekeeping - 36 species, which are feed for wild and domestic animals - 22 species. Edible plants used in nature or serving as raw materials for the confectionery, brewing, distillery -18 species. There are 13 industrial plants used to optimize technological processes in the production of consumer goods and for other purposes. Plants used in cosmetology and perfumery industry -17, poisonous - 6 species. Herbaceous perennials - 27 species prevail, annual herbaceous plants - 7, shrubs - 2 species. Mesophytes - 44.4%, xeromesophytes –22.2%, mesogyrophytes –16.7%, hygrophytes and xerophytes 8.3% each. Mesotrophs - 86.1%, eutrophs - 13.9%, photophilous - 91.7%, shadow-hardy - 8.3%. Resources sufficient to maintain blanks in case of demand for their raw materials have: Phlomistuberosa L. and Schizonepetamultifida (L.) Briq. The resources of Dracocephalumnutans L., Dracocephalumruyschiana L., Galeopsisbifida Boenn., Glechomahederacea L, Thymus pavlovii Serg allow the collection of raw materials in limited volumes.

Keywords: Lamiaceae family (Lamiaceae), medicinal plants, food plants, industrial plants, ornamental plants, biomorphs, resources.

Abstract: Irkutsk region is one of the main territories of Russia, with more than 80% forest cover, including valuable coniferous species. However, the influence of abiotic and anthropogenic factors leads to the depletion of the forest Fund. Therefore, it is no coincidence that it is important and necessary to solve the problem of restoring forest-seeded objects. The first attempts at artificial afforestation were made in the late 40s of the XX century. Despite the official orders, the work on the creation of forest seed facilities was not carried out enough. In the period of the 70s and 80s of the XX century. on the territory of the region in the Kirov specialized seed forestry normal plantings occupied 98.4% of the area, and negative-1.6 %. Previously, the Institute "Soyuzgiproles" in 1966 determined the necessary objects for the subsequent organization of forest seed farming. Based on the data obtained in 1967, is composed of “the Project of organization of production-demonstration seed farm on pine in the Kirov sparseness Irkutsk region” and later, in 1976, developed by design create the seed plantation of Scots pine on the area of 174.2 ha. Based on the results of the activities of the certification Commission in 2014, an inventory of forest seed production facilities was conducted in the Irkutsk region. As a result of the assessment of the condition of objects, permanent forest-seed plots (PLSU) that do not meet the requirements of GOST 56-35-96 were identified. There was a mass drying up of plantings of PLSU that is connected with damages or pests or diseases. The total damaged area was 72.9 ha. Plus plantings on an area of 201.4 ha (common pine) were lost and were subject to write-off

Keywords: Irkutsk region, forest seed objects, ordinary pine, activities of the certification commission.

Abstract: The study of the influence of rosehip (Rosa eanina L) with different levels of vitamin C, growing in different regions of the Republic of North Ossetia-Alania, on the physiological state and metabolism of laboratory animals, taking into account the increased background of heavy metals in their diets, was conducted from 2016 to 2019. According to the results of chemical analysis of samples of rosehip fruits taken in all regions of the Republic of North OssetiaAlania, the reverse biological relationship between the content of vitamin C and heavy metals was established. Moreover, the highest level of ascorbic acid and low levels of zinc, lead and cadmium were distinguished by samples of rosehip growing in the Irafsky district of the region. The most favorable effect of lead intoxication on the growth of rats of the “Wistar " line” we added additives to the diet of a sample of rosehip powder with the highest concentration of vitamin C, which was shown in the reliable superiority of animals of the 2nd experimental group over control analogues in terms of live weight gain. The use of rosehip fruit powder with a higher concentration of vitamin C helped to improve the physiological and behavioral parameters of the animals of the 2nd experimental group. Feeding a sample of rosehip fruit powder with a higher level of vitamin C had a more favorable effect on the morphological and biochemical parameters of the blood of rats with excessive intake of lead into the body. Due to the high antioxidant and adsorption properties of vitamin C with the best level of detoxification of heavy metals in the body, animals of the 2nd experimental group also differed, in which the lead content was significantly lower (P>0.95) in liver samples by 2.43 times and in blood by 1.70 times compared to the control (intact) group.

Keywords: laboratory animals, rose hip, vitamin C, heavy metals, growth, behavioral indicators, blood, liver, detoxification.

Abstract: The material was hearts from males of the Baikal seal of two ages of 5-6 months (n = 3) and 1.5-year-old (n = 3). In the work used generally accepted methods: the manufacture of corrosive preparations, thin preparation of blood vessels, photographing, morphometry (diameter and length vessels) using an electronic caliper (Stainless Hardened LR44), the angle of passage of arterial vessels using a protractor. Studies have shown that the Baikal seal has a left-wing type of blood supply, as indicated by a 1.5-fold excess in diameter and a relatively developed network of branches of the left coronary artery. The left coronary artery in the Baikal seal is dichotomously divided into the paraconal interventricular artery and the circumferential branch. In the paraconal artery, permanent and large branches are the branch of the interventricular septum and the diagonal of the left ventricle, as well as smaller from 11 to 13 branches into the myocardium of the right ventricle, and from 8 to 9 branches into the myocardium of the left ventricle. The envelope branch is formed by three main (atrial, diagonal and intermediate) and gives from 3 to 4 branches to the left atrium, and from 8 to 10 branches of arteries to the base of the left ventricle. The diagonal branch of the envelope artery, which branches independently or in the form of two branches (16.7%), is subject to the greatest variability. The right coronary artery in the Baikal seal gives up the subsinous artery, from which there are 15 or less small branches to the base of the right ventricle and the atrial septum, and from 5 to 7 branches to the atrium of the right ventricle. The diameter in the vessels of the heart increases with age, the largest value is observed in the envelope of the left ventricular artery by 1.5 times and its branches from 1.4 to 1.7 times, and the smallest value in the paraconal artery is 1.1 times and its diagonal branch 1.01 times. The length of the vessels of the heart also increases with age.

Keywords: Baikal seal, blood supply to the heart, right and left coronary arteries, branches