Approximately 68 % of the world’s population suffers from iodine deficiency, and more than 70 % of Russia’s territory, including Crimea, is classified as an iodine-deficient area. Salt iodination only does not solve this problem and has a number of negative effects. The review examines factors that cause the development of iodine deficiency in soils and fresh water. It is shown that climate aridity contributes to the development of the element deficiency in the environment. In water, iodine content positively correlates with salinity. Seaweeds, especially brown algae, have long been used to combat iodine deficiency. However, to overcome the problem of iodine deficiency it is more suitable to use green macroalgae from saline and hypersaline waters, having great potential as fertilizers, food and fodder additives. In hypersaline water bodies filamentous algae Cladophora have a high content of biomass – 2.25 kg dry mass/m² and have great productivity – up to 1 kg (dry mass)/m² /week, which is two orders of magnitude higher than that of terrestrial plants and significantly more than that of brown algae. The experimental data on the use of a feed additive from Cladophora (1 % of the diet) in feeding rabbits, chickens, and other animals are summarized. Calculations are made showing that the natural resources of green filamentous algae Cladophora, which have enormous productivity, are quite sufficient to solve the problem of iodine deficiency.

Fertilization is a complex process that results in the fusion of gametes. In order to obtain fertilizing ability, spermatozoa need to undergo post-ejaculation processes in the female reproductive tract. These include capacitation, hyperactivation, and acrosomal reaction. Capacitation is a complex process during which the sperm undergoes various changes in metabolism, intracellular concentrations of ions and other substances. The main factors of capacitation are the concentration of intracellular calcium ions, changes in the properties and structure of the plasma membrane, the pH of the medium, as well as the effect of progesterone and cholesterol on the sperm. The resulting hyperactivation leads to a change in the motility of the sperm, as a result of which it reaches the egg for further penetration into it. Then an acrosomal reaction occurs – the release of substances from the acrosome that ensure penetration through the transparent membrane of the oocyte. The fertilizing ability can be determined by various methods: the HBA test is based on the binding of spermatozoa to hyaluronic acid, SpermSlow is used to slow down spermatozoa in a hyaluronic-containing medium. The integrity of the acrosome and the motility of the sperm can be determined using the Acrobeads method, based on the formation of a complex of motile spermatozoa with immunoglobulins coated with antibodies against the protein from the inner surface of the acrosomal membrane. The SPA method allows us to determine the functional ability of spermatozoa to bind to the egg shell. In addition to direct methods that examine the basic parameters and functions of the sperm, there are methods that determine additional parameters, such as the level of oxidative stress and the factors that cause it, and the presence of disorders in the genetic apparatus of the male gamete. The level of oxidative stress and the amount of reactive oxygen species can be determined by reaction to thiobarbituric acid, reaction with nitrosine tetrazolium, by estimating the amount of carbonyl derivatives of amino acid residues in proteins, and by chemoluminescence analysis. DNA breaks can be detected using the TUNEL test, the DNA comet method is used to identify the degree of damage to genomic DNA, and the FISH method is used to analyze the chromosome set of a sperm cell. The cervix contains cervical mucus, which is a necessary factor for fertilization. The ability of spermatozoa to penetrate through it can be determined using auxiliary methods, for example, swim-up. Its essence lies in the fact that in a cultural environment, the natural movement of male gametes is imitated, and those that meet the requirements are selected. The concentration of spermatozoa and the degree of their motility in the cervical mucus are determined by a postcoital test. Taking into account the availability of these techniques from a logistical point of view, the development of domestic kits is relevant.

There are various types of feed additives: amino acids, minerals, vitamins, probiotics, prebiotics, hormones, and enzymes. Biologically active additives used both in their natural form and in a complex accelerate metabolism which leads to increased productivity and improved quality of products obtained from animals. Macro- and microelements have a good effect on the metabolism in the body of cows, the amount of milk yield, the composition of milk and its technological properties. Scientists have proven that the main limiting amino acid for ruminants is methionine, and with the addition of lysine and methionine together to the basic diet, additional milk yield is obtained. There is evidence that probiotics combined with prebiotics have proven themselves positively, such a combination is called "synbiotics". These two products purposefully support each other, which is the most likely approach to reducing the number of pathogens in dairy products. Currently, the most widely used enzyme preparations in animal husbandry are compositions containing xylanase, cellulase, and beta-glucanase. The cellulase enzyme significantly improves the daily milk yield, fat content and fatty acid composition of milk, as well as improves the absorption of nutrients. At the same time, the exogenous enzyme xylanase has no effect on milk yield and contributes to a decrease in the efficiency of feed use in cows at the beginning of lactation. Thus, biologically active additives, both in their natural form and in a complex, make it possible to optimize the nutrient content in the body, improve scar digestion, increase milk yield and biological value of milk, and also have a positive effect on the reproductive ability of cows.

The work was carried out in soil and climatic conditions of the Kirov region. In competitive cultivar testing (2021–2024), the economic and biological indicators of new winter rye cultivar ‘Lika’ were studied in comparison with the ‘Falenskaya 4’ standard and the cultivar ‘Batist’, included in the State Register of Breeding Achievements in 2023. To assess the adaptive indicators of ‘Lika’ cultivar the method of A. V. Kilchevsky and L. V. Khotyleva was used, according to which the parameters of general and specific adaptive ability (GAA_i and σ²SAA_i) and the selection value of the genotype (SVG_i) were calculated. The parameters of ecological plasticity and stability of traits (regression coefficient b_i and standard deviation from the theoretical regression line 𝜎_𝑑²) were calculated according to the method of S. A. Eberhart and W. A. Russell as presented by V. Z. Pakudin. The weather conditions of the spring-summer vegetation period were contrasting (hydrothermal coefficient – 0.75...2.14), which made it possible to evaluate the adaptive potential of the new cultivar comprehensively in a changing environment. The cultivar ‘Lika’ belongs to the group of mid-late cultivars, has a strong stem of medium thickness and lodging resistance at the standard level (3.2...5.0 points). Winter hardiness of the new cultivar is at the level of the highly winter-hardy standard ‘Falenskaya 4’ (4.5...5.0 points), which indicates high resistance to unfavorable wintering conditions. Grain of ‘Lika’ cultivar is intended for food use, is characterized by good baking properties: falling number 154...250 sec; grain unit 694...713 g/l; protein content 11.1...11.6 %. The new cultivar is distinguished by stable yield over the years – 4.30...5.44 t/ha, which is at the level (2021, 2024) or significantly higher (2022, 2023) than the ‘Falenskaya 4’ standard. In comparison with the standard and the cultivar ‘Batist’, the cultivar ‘Lika’ was characterized by a better combination of plasticity (b_i = 1.11) and stability (𝜎_𝑑² = 0.009), higher general adaptive ability (GAA_i = 0.15) and selection value of the genotype (SVG_i = 2.44). According to the results of state cultivar testing, since 2025, the cultivar is included in the Register of Breeding Achievements in the Northern and Volga-Vyatka regions of the Russian Federation. The cultivar ‘Lika’, due to its high productive and adaptive potential, is promising for use in agricultural production in the conditions of northern farming.

Cell selection is actively used to create genotypes of grain crops resistant to edaphic stressors. It is necessary to evaluate the genotypes selected in vitro under in vivo conditions to confirm the genetic stability of the target trait. To increase the yield of regenerated genotypes, it is possible to use growth regulators with adaptogenic and protective effects. In the conditions of a vegetation experiment, a comparative analysis of the productive traits of ‘Boyarin’ barley (Hordeum vulgare L.) cultivar and its regenerated R1-generation lines was carried out on soil backgrounds with drought (рНКCl – 6.5; artificially created water deficit), aluminum toxicity (рНКCl – 4.8; Al – 13 mg/kg) and cadmium (рНКCl – 4.7; Cd – 6.4 mg/kg), also without stress (control). The efficiency of barley treatment with salicylic acid (SA) (2 mM/dm³) as a stress protector under unfavorable soil conditions was assessed. The contribution of factors to the formation of barley yield was determined: soil background – 30.4 %, genotypic features – 8.1 %, treatment with salicylic acid – 0.7 %. Without SA treatment, the highest yield (130 g/m²) under stressful (drought) conditions was shown by regenerants obtained on selective media in vitro with water deficiency – RA-PEG. The stressprotective effect of SA was revealed against the background of cadmium in the regenerants RA-Cd and RA-PEG, the yield excess was more than twice over the original cultivar, amounting to 59 and 47 g/m², and in the absence of stress factors – in the regenerants RA-Al and RA-PEG by 29 and 24 g/m2 , respectively. The regenerated line RA-PEG is recommended for use in breeding programs to create drought-resistant genotypes.

The purpose of the research is to study different in ecological and geographical origin fiber flax genotypes in terms of flax fiber productivity, adaptability and environmental sustainability in the Pskov region (North-Western region of the Russian Federation). The evaluation of 20 cultivars of flax from the collection of the All-Russian Institute of Plant Genetic Resources named after N. I. Vavilov was carried out in 2021–2023 in comparison with the standard ‘Dobrynya’ cultivar. The most favorable hydrothermal conditions of the growing season for the growth and development of flax were formed in 2022, when the hydrothermal coefficient (HTC) was 1.43, and the environmental conditions index (Ij) was +28.1); unfavorable – in 2021 (HTC = 2.07; I_j = -37.8). The average annual yield of flax fiber in these years was 202.8 and 136.9 g/m², respectively. The average yield of the cultivars for 2021–2023 ranged from 117.0...220.7 g/m². Of the 20 cultivars tested, 10 exceeded the average grade yield (174.7 g/m2), 7 exceeded the standard ‘Dobrynya’ cultivar (190.2 g/m²). A statistically significant excess of yield over the standard was noted in cultivars from France (‘Bolchoi’ – 220.7 g/m², ‘Olga’ – 214.5 g/m²) and Belarus (‘Vesta’ – 213.3 g/m²). The cultivars differed considerably in the degree of adaptability and environmental sustainability, as evidenced by significant fluctuations in the values of the indicators: coefficients of variation (CV) – 9,0...38,8 %, adaptivity (KA) – 67.0...126.3 %, plasticity (bi) – 0.41...1.82, stability (Gd2 ) – 2.5...2385.5; yield range (d) – 14.3...62.3 %; stress resistance (Y2 - Y1) – -24.3...-108.2 g/m², genetic flexibility (Y1 + Y2)/2) – 111.8...223.1 g/m², homeostaticity (Hom) – 17.6...58.0, general adaptive capacity (GAC) – -51.5...+46.0 g/m². Based on a comprehensive assessment of flax fiber yield and the above-mentioned indicators, taking into account the ranking principle, highly productive cultivars have been identified that are most adapted to the conditions of the North-West of Russia: ‘Dobrynya’, ‘Tonus’ (Russia); ‘Vesta’, ‘Grant’ (Belarus); ‘Kamenyar’ (Ukraine); ‘Bolchoi’, ‘Olga’ (France), which will be used in breeding for adaptivity.

The aim of the study is the determination of the effect of increasing the photosynthetic photon flux density (PPFD) from 100 to 200 μmol/m²s on the in vitro growth, development and morphogenesis of single-node cuttings of potatoes of different cultivars. The following cultivars were involved into the investigation: ‘Krasa Meshchery’, ‘Sadon’ (Lorkh Federal Research Center of Potato), ‘Bylina Sibiri’, ‘Irtysh’ (Omsk Agricultural Scientific Center). The increase in PPFD was accompanied by a shortening of shoots by 12–32 %, depending on the cultivar, and a decrease in the number of internodes for all varieties by at least 10 %. A redistribution of biomass accumulation towards the root system was observed for all cultivars except the ‘Irtysh’ cultivar. The cultivars bred by the Lorkh Federal Research Center of Potato formed firm leaves. The ‘Irtysh’ cultivar showed a decrease in the content of chlorophylls and carotenoids, while the ‘Krasa Meshchery’ cultivar showed an increase. The area of the 4th leaf of these cultivars was maximum at 200 μmol/m²s. The stability of the electron transport chain of photosystem 2 to high PPFD increased, which is evident from the growth of chlorophyll A fluorescence parameters: maximum electron transport rate and minimum saturating light intensity, as well as the dynamics of rapid light curves of photochemical fluorescence quenching. Only the ‘Krasa Meshchery’ cultivar showed a decrease in F_v/F_m. Cultivar-specific reactions also included: a decrease in the proportion of plants with bushiness of the ‘Irtysh’ cultivar; an increase in the frequency of callus globule formation in the root zone and edema on leaves and shoots of Omsk-bred cultivars; and the formation of microtubers in the axil of the initiating cutting of the ‘Krasa Meshchery’ cultivar. Thus, increasing the PPFD to 200 μmol/m²s leads to the formation, for most of the studied cultivars, of plants that are more suitable for planting in soil or aeroponic/hydroponic conditions: low, with a well-developed root system, a larger leaf area and photosystems adapted to high light intensity. The exception is the cultivar ‘Krasa Meshchery’ due to the excessively short shoots (from 2 to 36 mm). For micropropagation, PPFD of 100 μmol/m²s is more suitable, with the exception of the cultivar ‘Irtysh’ due to the frequency of bushiness increasing under these conditions.

One of the promising directions for increasing the productivity of potato growing is the creation and implementation of promising high-yielding cultivars adapted to local environmental conditions. The purpose of the research is to identify new potato genotypes to create cultivars that are maximally adapted to the natural and climatic conditions of Dagestan. For the period of 2021–2024 in various natural and climatic zones of Dagestan, due to the vertical zonation of its territory (foothills, mountains and highlands), hybrid forms of various genetic origin, obtained from the collection of the potato gene pool of the Federal State Budgetary Scientific Institution "Federal Potato Research Center named after A.G. Lorkh” have been tested. Based on the assessment of the breeding material according to the "yield" trait when cultivated in various natural and climatic conditions of Dagestan, there have been selected 3 hybrid forms of potato of the middle-early ripening period – 2021.2797/4, 2021.2812/5 and 2021.2855/5. The yield of these hybrids was 28.6–133.0 % higher than that of the standard ‘Nevsky’ cultivar, depending on the place of cultivation. The average yield indicators for cultivation zones in hybrid forms 2021.2797/4, 2021.2812/5 and 2021.2855/5 were 48.9; 56.6 and 40.7 t/ha, respectively. The content of starch in tubers was 14.5–16.5 %, the taste – 4.2–4.7 points, the storability – 94.6–95.7 %. The identified promising hybrid forms, distinguished by high productivity over the years of the research, will be used to create new potato cultivars highly adapted to the agroclimatic conditions of mountainous and foothill Dagestan.

The aim of the of research is to study the effect of mineral fertilizers, Vostok EM-1 biopreparation and Nanosilicon microfertilizer on phytosanitary condition of crops and yield of 7 winter soft wheat cultivars bred by FRC “Nemchinovka”.  The research was carried out in the Nizhny Novgorod region on light gray forest soil in 2022–2024. It was found that over the years of the research the degree of snow mold infection of winter wheat cultivars was significant and averaged 2.77 points  (from 1.8 to 3.8 points over the cultivars); the prevalence of brown rust ranged from 13.1 to 33.1 %, and averaged 23.3 %;  the spread of septoria infection varied from 55.3 to 88.2 % (on average, 69.0 %). The use of the Vostok EM-1 biopreparation during seed inoculation as well treatment of plants during the tillering phase of winter wheat with Vostok EM-1 and Nanosilicon preparations did not affect significantly the prevalence of brown rust and septoria in the crops of winter wheat during the years of the research. The yield of winter wheat cultivars varied on average over the years of experimental observation from 5.04 t/ha (‘Nemchinovskaya 17’ cultivar) to 6.91 t/ha (‘Moskovskaya 82’ cultivar). In arid conditions of vegetation (May-June 2022– 2024) the application of mineral fertilizers in doses N₁₀P₃₀K₃₀ + N₅₀ and N₂₀P₆₀K₆₀ + N₁₀₀ increased the average yield of winter wheat by 0.18 and 0.27 t/ha, respectively, compared with the variant without their use. Spraying wheat plants during the tillering phase with Nanosilicon microfertilizer and Vostok EM-1 biopreparation increased the average yield over the cultivars by 0.21 (3.9 %) and 0.55 (10.1 %) t/ha, respectively, compared with the control variant without treatments.

The purpose of the research was to study the complex effect of basic tillage techniques (moldboard plowing at 20–22 cm and combined boardless tillage at 14–16 cm) and mineral nutrition levels (without fertilizer, N₃₀P₃₀K₃₀, N₃₀P₃₀K₃₀ + OMF, N₃₀P₃₀K₃₀ + CAM, N₆₀P₆₀K₆₀) on the yield, yield structure indicators and grain quality of winter wheat of the ‘Moskovskaya 82’ cultivar. The research was carried out on sod-podzolic soil in the conditions of the Kirov region in 2022-2023. Organo-mineral fertilizer Polydon Amino Start (1 L/ha) and carbamide-ammonia mixture (CAM) (30 L/ha) were used for foliar fertilization during the tillering phase of the crop. Grain yield during the research years was 5.66–7.71 t/ha in 2022 and 2.63–7.25 t/ha in 2023, and was more dependent on the level of mineral nutrition. In 2023 there was a strong correlation between the yield, the number of ears per area unit, the number of grains per ear, and the weight of grain per ear (r – 0.76; 0.70 and 0.78, respectively). There was a significant increase in the number of productive stems in 2023 in the variants N₃₀P₃₀K₃₀ + CAM, N₆₀P₆₀K₆₀. The amount and weight of grain in the ear did not depend on the tillage method and the level of mineral nutrition. The weight of 1000 grains of winter wheat in 2023, when using moldboard plowing (57.3 g), was 2.2 g (LSD05 = 0.57 g) higher than when tilling with a combined unit (55.1 g). Thus, the studied factors had an impact only on the yield and weight of 1000 grains. Evaluation of the quality of winter wheat grain showed that the studied factors did not have a significant effect on the content of protein, fiber and ash. To a greater extent, these indicators were influenced by the weather conditions of spring and summer growing season: the share of influence on the amount of protein in the grain was 42.5 %, on the fiber content – 59.2 %. According to the State Standard-9353-2016 (Soft wheat. Technical specifications) on the protein content in 2022, grain of the 3rd and 4th classes was obtained, in 2023 – grain of the 3rd quality class.

The introduction of biological agents in crop production for protection, growth regulation and increasing crop resistance to biotic and abiotic stresses is becoming increasingly common. The aim of the study was to investigate the effect of siliceous humic preparations on potato yield and soil microbiological activity. The studies were conducted in the Tver region from 2020 to 2022. The experiments tested silicon (sodium silicate solution) and siliceous humic preparations developed at the All-Russian Research Institute of Reclaimed Lands (BoHum-S, nanoBoHum-S). Ultrasonic dispersion was used to obtain nanopreparations. The preparations were applied to tubers before planting (OK) at concentrations of 0.5 and 1.0 % and as a two-time foliar treatment (HO) of ‘Skarb’ potato plants during the "seedlings" and "budding" phases. The greatest increase in potato yield on average over three years relative to the control (without treatment) was noted in the variant using the nanosized silica-humic preparation nanoBoHum-S (OK, 1.0% + HO) – 1.7 t/ha, or 9.7 %. Statistically significant increases in potato yield in this variant were obtained in all years of testing. The yield increase is due to the increase in the share of the medium potato fraction due to the decrease in the small one. During the main phases of potato plant development, the number of autochthonous, ammonifying and phosphate-mobilizing microorganisms in the soil was counted using the limiting dilution method on agar nutrient media. Treatment of potato tubers with preparations contributed to the activation of the said microorganisms, their highest number was noted in the variant with the use of nanoBoHum-S (OK, 1.0% + HO). The number of the said microorganisms increased almost twofold in the germination phase, in the flowering phase the increase in ammonifying microflora was 36 %, phosphate-mobilizing – 43 %. Activation of autochthonous microorganisms affected the content of easily hydrolyzed nitrogen in the soil. When using the silicon-containing preparation nanoSi, an increase in the number of phosphate-mobilizing microorganisms and a decrease in the activity of ammonifying and autochthonous ones were noted.

The restriction of the use of antibiotics in poultry farming in many countries has fueled interest in alternative products such as herbal preparations (a group of natural products), which have been the subject of numerous studies in recent years. The aim of the study was to evaluate the effect of biologically active plant organic substances on the chemical, fatty and amino acid composition of muscles and liver of broiler chickens. The studies were performed on 125 7-day-old broiler chickens (Arbor Acres cross), divided into 5 groups (n = 25). The duration of the experiment was 42 days. The difference was that the control group received the basal diet; experimental group I – the basal diet + gamma lactone at a dose of 0.1 ml/kg of feed/day; experimental group II – the basal diet + gamma lactone at a dose of 0.1 ml/kg + cinnamaldehyde a dose of 55 mg/kg of feed/day; experimental group III – the main diet + gamma lactone at a dose of 0.1 ml/kg + 7-hydroxycoumarin at at a dose of 2 mg/kg of feed/day; experimental group IV – the main diet + gamma lactone at a dose of 0.1 ml/kg + cinnamic aldehyde at a dose of 55 mg/kg + 7-hydroxycoumarin at a dose of 2 mg/kg of feed/day. The study found that the young birds from the experimental groups exceeded their peers from the control group in fat accumulation in the pectoral muscles: I group by 0.43 %, II – by 0.88 % (P≤0.05), III – by 0.82 % (P≤0.05) and IV group – by 0.4 %. Birds from groups II and IV in terms of protein content in the femoral muscle exceeded their counterparts from the control group by 0.87 and 0.82 %, respectively. In the breast and thigh muscles of broilers of group III, fatty acids accumulated more compared to the control: palmitoleic by 0.5 and 0.3 %, stearic by 0.2 % (only in the thigh muscles), oleic by 1.1 % (P≤0.05) (only in the breast muscles), linoleic by 1.5 (P≤0.05) and 3.1 % (P≤0.01). When feeding pure gamma lactone with the diet, the highest deposition of arginine by 0.77 %, lysine by 2.64 % (P≤0.05), leucine + isoleucine by 2.1 % (P≤0.05), valine by 0.83 %, serine by 1.57 % (P≤0.05), alanine by 1.22 % (P≤0.05) in the femoral muscles was observed in relation to the control group.

The aim of the research was to study the content of 20-hydroxyecdysone in phyto-additive from Leucea safflower and its effect on metabolic processes in young laying hens of the Lohmann Brown Light cross. The concentration of 20-hydroxyecdysone in phyto-supplement under study was 0.40±0.05 % on absolutely dry matter. Phyto-additive from the green mass of Leucea safflower was included into the compound feed from the 2^nd to the 23^rd week of growing young laying hens: at a rate of 3,0 % in the first experimental group and 6,0 % in the second group, based on the dry matter content of the feed. The duration of feeding was 154 days. As a result of the experiment, it was revealed that the young laying hens of the first and second experimental groups had higher digestibility coefficients compared to the analogues of the control group: of dry matter by 3.20 and 7.21 % (p<0.01), of organic matter by 2.90 % (p<0.05) and 5.70 % (p<0.01), of crude protein – by 5.68 and 7.47 % (p<0.05), of crude fat – by 4.60 and 6.07 % (p<0.05), of crude fiber – by 4.94 and 8.14 % (p<0.05), and of nitrogen-free extractive substances – by 1.36 and 2.31 %, respectively. The coefficients of nitrogen assimilation in poultry of the experimental groups were higher by 1.89 р. р. (p<0.01) and 4.58 р. р. (p<0.001), respectively. In the young laying hens of the first and second experimental groups, the coefficients of calcium and phosphorus utilization were higher, compared with the poultry of the control group, by 1.42 р. р. (p<0.05) and by 3.57 р. р., 1.44 р. р. and 3.50 р. р., respectively. The level of total protein in the blood of young laying hens of the first and second experimental groups was at the upper limit of normal and was higher by 9.13 % (p<0.05) and 12.22 % (p<0.01), respectively, compared with the control. The live weight of young chickens in the first and second experimental groups at the end of the experiment, was 101.02 % and 105.52 %, respectively, relative to the control. In order to improve the metabolic processes in the body of the poultry, it is more appropriate to include a feed phyto-additive from Leucea safflower in the amount of 6.0 % (in% to the weight of the dry matter of the feed) in the structure of compound feeds for young laying hens.

In modern dairy farming, genealogical lines are traditionally used to predict productivity, but their effectiveness remains controversial. In this work, based on the analysis of 38 scientific publications (2012–2024) and original data from 762 Holstein cows in the Sverdlovsk region (Russia), there has been studied the relationship between lineage affiliation of the most common Wis Burke Ideal (WBI) and Reflection Sovereign (RS) lines and milk productivity indicators (milk yield over 305 days of the first lactation, fat and protein percentage in the milk). Analysis of scientific sources showed that only eight out of thirty-eight studies were noted by statistically significant differences, while the results concerning differences in productivity indicators among different lines were not conclusive. Statistical analysis of the original data (Shapiro-Wilk test, MannWhitney U-test) revealed non-normal distribution and limited significance of differences between lines in terms of productivity indicators. Line purity of bulls whose semen is used in the region has been lost by the third generation already. Genetic analysis made it possible to reconstruct genealogical connections and demonstrated interline mixing in breeding stock, specifically, 40 % of kinship relationships turned out to be inter-lineage. Evaluation of genetic differentiation (FST) indicated no difference between WBI and RS lines, whereas genealogical communities within the population exhibited greater genetic distinctiveness. The results prove that genealogical lines cannot serve as reliable tools for predicting productivity due to insufficient statistical significance, high degree of mixing, and lack of genetic uniqueness. According to the research results, it is recommended to take the transition to genomic selection methods that consider individual genetic markers rather than lineage affiliation.

In recent years, there has been a significant development of technologies in the field of genetics and breeding of cattle, which opens new opportunities for increasing productivity and quality of dairy products. The present work is devoted to the study of genetic determination of technological properties of cow milk, namely, thermostability and rennet coagulation.

The aim of the study was to perform a genome-wide association analysis (GWA) to identify positional candidate genes determining the formation of cow milk technological traits, followed by functional annotation for a thorough understanding of the mechanisms of gene action and their contribution to phenotype formation. As the result of GWA analysis there were identified 17 SNPs significantly associated with milk thermal stability located on chromosomes BTA3, BTA6, BTA8, BTA23, BTA24, BTA27, BTA28 and BTA29. There were also identified 34 SNPs associated with milk rennet coagulation localized on chromosomes BTA1, BTA2, BTA3, BTA5, BTA6, BTA9, BTA10, BTA12, BTA14, BTA15, BTA16, BTA18, BTA20, BTA23, BTA24, BTA26 and BTA27.Functional annotation revealed 144 genes grouped into 43 nodes and nine clusters. Among all nine clusters, four of them involved genes responsible for thermostability (CNOT7) and rennet milk coagulation (HHAT, NEDD9, ZNF423). Functional annotation of 11 identified candidate genes (HHAT, PDE3B, AK8, AK2, CNOT7, XRN2, NOP14, NEDD9, SMAD3, ZNF423, EBF1) using the DAVID database identified their involvement in biological processes such as protein palmitoylation, regulation of cellular activity, nucleotide biosynthesis and translation regulation. Associations between individual genes (HHAT, AK8, EBF1) and QTLs affecting milk productivity and milk quality composition were also identified. The results of the study contribute to the understanding of the genetic architecture of technological properties of milk and can be used in genomic selection to improve the quality of dairy products.

The increase of productive longevity of dairy cows is a current problem in the animal breeding. In this regard, the study of changes of geriatric parameters in elderly cows and the evaluation of preparations affecting gerontological processes is an important scientific and practical task. The effect of recombinant colicin E2 on some geriatric parameters of lactating cows aged 5-6 years over a period of eight months has been studied. Two groups of healthy lactating cows (control and experimental) of eight heads each were formed. During the experiment the medicine was introduced to the cows of the experimental group intramuscularly in the dose of 500 mg twice a month. During the experimental period the blood of the control group showed a 40 % decrease in the telomere length of lymphocytes and an 8 % decrease in the amount of melatonin. The amount of inflammatory mediators increased significantly in the blood of control animals - prostaglandin E2 from 86.4±7.1 pg/ml to 124.5±5.2 pg/ml (P<0.05) and matrix metalloproteinase from 14.8±0.2 ng/ml to 34.2±0.5 ng/ml (P<0.05). By using the recombinant colicin E2 in cows of the experimental group, no decrease in the telomere length of lymphocytes was detected. Increase in the quantity of interleukin 4 and interferon alpha in the blood was noted. Stimulation of cytokine production of interleukin 4 and interferon alpha by recombinant colicin E2 in the blood of cows of the experimental group regulated the activation of lymphocytes having receptors to melatonin. The quantity of melatonin in the blood of experimental cows increased from 28.6±0.8 pg/ml to 38.5±1.4 pg/ml (P<0.05), and the quantity of matrix metalloproteinase remained stable.

The black grouse (Tetrao tetrix L., 1758) is a terrestrial and arboreal species of the pheasant family, inhabiting the temperate latitudes of the northern hemisphere. The cosmopolitan range covers the forest-tundra, taiga, forest-steppe and partly steppe zones of Europe and Asia from the Alps to the Amur basin. In Western Europe, the modern distribution of the black grouse is mosaic, the trend of the dynamics of most populations is negative. The use of the species' resources is limited. In Russia, including the Kirov region, the black grouse is one of the most significant and widespread species of hunting resources. The problems of resource dynamics and the estimation of the species stock use level are considered in the research on the example of the Kirov region. The current bird population in the region, according to various estimates, is 362.9–440.7 thousand individuals. The official hunting bag of the species in the region is at the level of 6217 individuals. Alternative estimation methods indicate an annual bag of approximately 58.5 thousand individuals. The ratio of bag volumes by seasons is similar. Currently, the provision of services for organizing black grouse hunting in the region is sporadic. The products obtained as a result of using the black grouse population in the region are determined. Hunting products include food raw materials (meat), as well as derivatives that are used for taxidermy products and souvenirs. During the research the volumes of each type of product received have been estimated and recalculated in monetary terms.

The purpose of the study is to develop a technology that ensures quick, simplified, and environmentally friendly processing of fresh manure and droppings, as well as to determine the composition of the separated fractions. The research was conducted in 2023-2024 in the Stavropol Territory. There has been developed a line of technological equipment for processing fresh manure and droppings, which consists of a storage tank, a submersible homogenizer screw, a submersible pump, a press separator, a container for the solid fraction, and a container for the liquid fraction. On one side of the press separator there is an electric motor, and on the other side there is an opening with a lid on a spring for the exit of the solid fraction. As a result of the technological process, the solid fraction is collected in containers, and the liquid fraction flows through the outlet pipe into the tank for the liquid fraction. Fractions were sampled during the first 3 days from the moment of production and sent for toxicological and agrochemical studies in certified laboratories according to approved methods. As a result, it has been established that the use of a technological equipment line, the distinctive feature of which is the loading of fresh manure into a storage tank pre-filled with water in a ratio of fresh manure or droppings and water from 1.0:1.5 to 1.0:2.5 m³, should solve the problem of eliminating the negative impact of ballast foreign mechanical inclusions on equipment wear; reduce the hazard class of fresh manure/ droppings up to V (practically non-hazardous waste); agrochemical, bacteriological and parasitological composition of liquid and solid fractions corresponded to the requirements of GOST for organic and mineral fertilizers. The obtained liquid fraction can be immediately applied to the soil as a bioorganic fertilizer, and the solid fraction can be used as a substrate for the vital activity of earthworms or composted. In both cases, the processing time of the obtained solid fraction is reduced to one and a half or two months.

In the context of the looming global food crisis, the intensification of food production is becoming not so much a commercial issue as a factor of survival for all of humanity. The role of countries with the necessary resources and production capabilities for mineral fertilizers, which is a key component of the intensification process in crop production, is becoming increasingly important in addressing this challenge. The aim of the research was to study the state of exports and domestic use of mineral fertilizers, in particular, to identify the reasons for the decrease in domestic consumption of mineral fertilizers, and to calculate the economic benefits of various scenarios for their use. The research was based on the regulatory documents, conclusions contained in scientific articles, monographs, statistical data, and expert opinions on the production and use of mineral fertilizers in modern Russia. The results of the study, which are scientifically novel, include: the calculation of the prospective capacity of the domestic mineral fertilizer market, taking into account the introduction of currently unused arable land and the reduction of mineral fertilizer application rates to the level stipulated by the optimal scenario for domestic use; the results of a comparative analysis of mineral fertilizer exports and domestic use, which clearly demonstrate the benefits of increasing domestic consumption and its economic impact, which is estimated at 982.4 billion rubles per year for grain alone. The practical significance of the research results is that they can be used in the development of a "road map" for restructuring the use of mineral fertilizers in order to increase domestic consumption by reducing their export.

In the first issue of the journal «Agricultural Science Euro-North- East" of 2021, there was published the article "Who decides which tractors an agricultural producer needs?" revealing the situation in the domestic tractor industry. After 4 years, there was an urgent need to return to this topic. One of the estimation indicators characterizing the level of development of the country's agricultural sector is the energy ratio, which takes into account the amount of energy per certain area of agricultural land. This indicator characterizes the ratio of the total capacity of the fleet, of tractors, self-propelled combines, electric motors available on the farm to the arable land area of the farm. The energy-to-weight indicator is usually used in the macro-assessment of the level of mechanization of regions and countries. In the proposed material, an attempt is made to assess the energy capacity of the agricultural sector of the Russian Federation specifically for tractor power, taking into account the purpose of the tractor. Currently, the Russian agricultural complex is experiencing an acute shortage in tractor energy. This is especially true for universal row tractors. This is explained by a number of reasons, the main one of which is certainly the policy of the federal agency responsible for this area. The purpose of this article is to show the real state of affairs in the tractor fleet of the agricultural sector of the Russian Federation as a whole, and in the federal districts in particular, and based on the data obtained to predict the prospects for further development of the agroindustrial complex of the country. The research materials included speeches by senior officials of political and government structures, representatives of science and industrial production, and official data from the Federal State Statistics Service.