The study presents the results of a literature review and original research on the influence of mitochondrial DNA (mtDNA) haplotypes on oocyte quality and genetic diversity in pigs of different breeds, based on the analysis of mtDNA polymorphism. mtDNA pathologies in oocytes arise from various factors such as aging, metabolic disorders, obesity, and reduced genetic diversity. A direct effect of mtDNA haplotypes on pig reproduction has been established, which contributes to a better understanding and diagnosis of pathologies underlying oocyte health deterioration. Three groups of mtDNA haplotypes were identified in Russian pig breeds, indicating limited genetic diversity. It was shown that sows with haplotypes D and E exhibit earlier oocyte maturation compared with offspring predominated by haplotype A, which demonstrated the lowest reproductive efficiency. According to the results, haplotypes D and E are more stable in pig populations, as litters from their carriers averaged 12 or more piglets born. The obtained data demonstrate a correlation between genetic variability in natural mitochondrial haplotypes and the number of piglets per litter. Analysis of mtDNA mutations in sows is an important tool for studying the influence of haplotypes on oocyte maturation and for predicting embryo survival in the maternal organism. Thus, improving oocyte quality through mitochondrial enhancement appears to be a novel approach to managing reproductive outcomes and determining sow productivity. It can be assumed that markers of mitochondrial dysfunction in high-quality oocytes may serve as prognostic indicators in assisted reproductive technology protocols.

For the first time in the history of Russian veterinary medicine, a retrospective analysis of the clinical features of brain tumors (BT) in dogs was carried out. The study was conducted in the Moscow region in 2018-2024 on the basis of the Biocontrol veterinary clinic. The aim of the study is to determine the frequency, localization and clinical manifestations of BT. The data of 54,142 dogs were analyzed, of which 150 had BT (1.2% of oncological cases, 0.28% of the total number of patients). The average age was 9.4 years. Most often, BT was recorded in cross-breed, French bulldogs, Cane Corso and German shepherds. Brachycephalic breeds showed a predisposition to intra-axial lesions, mesocephalic to extra-axial. There was no gender predisposition. The main clinical manifestations included convulsions, ataxia, paresis and changes in consciousness depending on the location of the tumor. The median tumor volume was 6 cm³ for extra-axial and 9.4 cm³ for intra-axial lesions. Histological verification was performed in 23 patients. Diagnosis was carried out using MRI (1.5 Tesla), histology and immunohistochemistry. The study showed the need for histological analysis of BT for accurate typing of lesions and emphasized the importance of developing methods of imaging and invasive diagnosis in veterinary medicine. The data obtained partially differ from foreign ones, which is due to the difference in the breed sampling of the dog population. Unique results can serve as a basis for the development of standardized protocols for the diagnosis and treatment of canine BT.

Under changing climate conditions, modern livestock production systems are becoming increasingly vulnerable, and highly productive animals are quite demanding in terms of housing and management conditions. An analysis of scientific studies dedicated to the problem of global warming and its impact on the dairy and beef cattle industries has been conducted. The research materials presented address the effects of heat stress on animals, noting the limited number of studies and the inconsistency of information available in the literature. Developments offering specific tools to mitigate the consequences of global warming for livestock enterprises are either absent or ineffective under the natural and climatic conditions of the Kabardino-Balkarian Republic.

The research was conducted in 2020-2021 at Leningrad Research Institute ‘Belogorka’ - a branch of Russian Potato Research Centre, located in the village of Belogorka, Gatchina district, Leningrad region. The research was carried out to identify sources of economically valuable traits from the collection of Vavilov AllRussian Institute of Plant Genetic Resources on the main elements of crop structure to create valuable breeding material for spring barley. In accordance with the Methodological Guidelines for the Study and Preservation of the World Collection of Barley and Oats (2012) and the International comecon list of descriptors for genus Hordeum L. (1983), 17 new spring barley cultivars of different ecological and geographical origins were studied over two years. Two cultivars were used as standards - Suzdalets (by yield) selected by several organizations and Leningradsky (by early ripening) selected by Leningrad Research Agricultural Institute ‘Belogorka’. The standard cv. Leningradsky surpassed cv. Magutny (Belarus) by early ripening in both years. 7 cultivars were identified (Dhow, Dokuchaevsky 15, Lun, Magutny, Mustang, J.B. Maltasia, and Kazak), for which maturation occurred 5-14 days earlier compared to standard cv. Suzdalets (growing season averaged 81 days over two years). According to productive tillers, 3 cultivars were identified that exceeded the standard cv. Suzdalets (3.0 plants): Magutny - by 0.3, Dhow - by 0.5 and J.B. Maltasia - by 0.6 plants. By weight of 1000 grains (more than 45.9 g), 6 varieties were identified: Rubiola, Shlyakhtsich, Beatrice, Magutny, Kazak and Lun. A cultivar resistant to powdery mildew in both years of study was distinguished - J.B. Maltasia. The selected cultivars will be used in the breeding process as genetic sources of agronomic traits in the conditions of the Leningrad region.

The search for alternative approaches to poultry farming aimed at improving the quality of meat and promoting health without the use of antibiotics is a vital task of modern poultry farming. Among the promising areas is the use as an alternative to antibiotics of complex multifunctional feed additives based on prebiotics, organic acids, and mineral components that contribute to the formation of healthy intestinal microflora, increasing the nonspecific resistance of poultry, as well as the quality of meat and productivity. The study is aimed at studying the effect of a new organo-mineral feed additive (OMFA) containing a prebiotic (lactulose), ultrafine silica dioxide particles, organic and amino acids, on the digestibility of nutrients, elemental, and amino acid composition of broiler chicken meat. The inclusion in the diet of a 4-component OMFA from the age of 7 and 15 days has a positive effect on nutrient absorption. An increase in the digestibility of crude protein, crude fat, and nitrogen-free extractives was noted. Early feeding period reduces the digestibility of crude fiber. The use of OMFA leads to an increase in the concentration of certain macro- and microelements in the tissues of broiler chickens, which has a positive effect on the quality of meat. The inclusion of OMFA in the diet is an effective way to optimize protein and fat metabolism, contributing to an increase in muscle mass and a decrease in the percentage of body fat. The ingredients of the feed additive increase the level of amino acids, which favorably affect the properties and nutritional value of broiler meat. When choosing the composition of the additive and the timing of feeding (from the age of 7 and 15 days), it is recommended to use a four-component OMFA for broiler chickens from the age of 15 days.

The results of experimental studies on field resistance of spring common wheat ( Triticum aestivum L . ) varieties to leaf rust in the Central Region of the Non-Black Soil Zone of Russia were described. Fifteen spring wheat varieties were evaluated under field conditions from 2021 to 2024. The study aimed to analyze the yield performance of these varieties depending on the effectiveness of resistance genes (Lr genes) against leaf rust in the Central Non-Black Earth region of Russia. A search for relevant publications and identification of Lr genes in the varieties was conducted using databases such as Wheatpedigree, Scopus, NCBI, PubMed, Google Scholar, RSCI, and Cyberleninka. Resistance to brown rust was assessed using the 9-point VIR scale. The results showed that in years with favorable weather conditions from sprouting to heading, resistance to leaf rust positively influenced grain yield. However, during drought periods, this resistance had no significant effect on yield. Lr resistance genes in the studied varieties provided relatively effective protection in years with low infection pressure, but were insufficient during epidemic years. Therefore, more effective genes or their combinations should be considered when developing new varieties for the Central Non-Black Earth region of Russia. The most effective resistance genes identified from 2021 to 2024 were Lr19 + Lr6 (from the donor variety Tulaykovskaya 108) and Lr21 (from the donor variety Granny).

The application of supplementary hemostatic techniques for the prevention of postoperative complications is becoming increasingly widespread. In cardiovascular surgery, wound sealing using surgical adhesives has proven effective; however, this method is rarely applied in gastrointestinal procedures. The present study examined various surgical adhesives and evaluated different approaches to closing gastrotomy wounds in rabbits using latex-based tissue adhesive and gelatin-resorcinol adhesive. A comparative analysis of these adhesives was performed based on their clinical efficacy, as well as pathological and histological findings. Clinically healthy laboratory rabbits were selected as experimental subjects. Surgical interventions were performed identically across all groups, with the only difference being the type of adhesive used. Postoperative monitoring included clinical examinations, pathological assessments, histological analyses, and hematological testing. Hematological studies revealed no correlation between the type of surgical adhesive and blood parameters. The study concludes that gelatin-resorcinol surgical adhesive represents the optimal choice for additional sealing of sutures. The research was conducted at the Department of Veterinary Surgery, Moscow State Academy of Veterinary Medicine and Biotechnology named after K.I. Skryabin.

This study presents the results of a comprehensive research of the composition and structure of microbial communities in the coastal soils of Kola Bay, Barents Sea, under conditions of anthropogenic pollution. A general decline in the taxonomic and functional diversity of microbial communities was observed. The most diverse and stable microbial community was found in the supralittoral zone soil, which is less affected by chemical pollution and subjected only to recreational pressure. The taxonomic structure of the microbiome in the oil-polluted zone showed an increased ratio of Proteobacteria among bacteria and Sordariomycetes among fungi, along with a decrease in community diversity and evenness. High levels of oil and heavy metal contamination led to an increased ratio of bacterial groups adapted to anaerobic conditions and parasitic groups of microscopic fungi. Significant positive correlations were found between oil product content and bacterial groups involved in sulfur oxidation, and negative correlations with nitrogen-cycle microorganisms and mycorrhizal fungi. A positive relationship was identified between mycorrhizal fungi and mineral nutrient elements, and a negative relationship between nitrogen-cycle functional groups and heavy metal content (Cr, Fe, Ni, As, Se, Mo). A decline in the abundance of hydrocarbon-oxidizing bacteria was noted in the oil-contaminated area, possibly indicating high toxicity of the pollution and insufficient efficiency of anaerobic degradation.

Apple tree ( Malus × domestica Borkh.) is a leading agricultural pome crop, one of the main perennial fruit plants in the world, commercially in demand and widespread in the horticultural industry of Russia, including the North Caucasus region. In solving the problem of creating high-quality domestic apple varieties with a long-term type of resistance to the scab (pathogen - Venturia inaequalis (Cooke) G. Winter), the role of prebreeding, including research aimed at accelerated selection using the DNA method, is significant tagging valuable carriers of several Rvi scab resistance genes. The purpose of the study was to study the allelic polymorphism of 15 apple tree scab resistance genes ( Venturia inaequalis (Cooke) G. Winter) in 33 varietal and breeding samples of apple trees to identify sources of long-term resistance to increase efficiency of breeding process. The research was carried out in accordance with programs and methods for the study of apple varieties; Research and Selection Collection of Genetic Resources of Horticultural Crops and the Instrumentation and Analytical Center were used. DNA analysis methods were used in this work. For DNA extraction, a modification of the CTAB method was used, developed at North Caucasian Federal Scientific Center of Horticulture, Viticulture, Winemaking, allowing for better purification of DNA samples from polyphenolic compounds. The work used 22 markers to identify 15 apple scab resistance genes: Rvi1; Rvi2; Rvi3; Rvi4; Rvi5; Rvi6; Rvi8; Rvi9; Rvi11; Rvi12; Rvi13; Rvi14; Rvi15; Rvi16; Rvi17 . Marker selection of new varietal and breeding material made it possible to identify carriers of several genes for apple tree resistance to scab, having in the genome from 2 to 6 different Rvi genes in different combinations. Carriers of 6 resistance genes were identified as the most promising for selection for long-term resistance to scab: Rvi1, Rvi2, Rvi3, Rvi4, Rvi6, Rvi15-1 2/1-21-24; 5 genes: Rvi1, Rvi2, Rvi3, Rvi6, Rvi13 - Karmen; Rvi1, Rvi2, Rvi4, Rvi6, Rvi15 - Mikhsan; 4 genes: Rvi1, Rvi2, Rvi3, Rvi6 - Nadezhnoye; Rvi1, Rvi4, Rvi6, Rvi15 - Gaito Gazdanov; Rvi1, Rvi3, Rvi6, Rvi8-1 2/1-20-56, etc. Identified apple genotypes of domestic breeding, including those created in creative collaboration with colleagues from the Russian Research Institute for Breeding Fruit Crops and Stavropol Experimental Horticulture Station, promising for further breeding and accelerated creation of new high-quality, adaptive varieties with long-term high potential for resistance to the main fungal pathogen of the crop.

In modern dairy farming, the study of genetic factors affecting the productive longevity and milk productivity of cattle is relevant. The leptin gene, involved in the regulation of energy metabolism, is a promising marker for selection. However, the influence of its polymorphism complex genotypes (A80V, R25C, Y7F) on the productivity and longevity of animals has not been sufficiently studied, which determines the importance of this research. The aim of the study was to investigate the influence of the leptin gene complex genotypes at sites A80V, R25C, Y7F on the milk productivity indicators and the duration of economic use of Kholmogory cattle. The study was conducted on 207 Kholmogory breed cows, divided into groups with different complex genotypes. For statistical analysis, the number of animals in the compared groups was equalized: 13 heads per group for the study of lifetime milk productivity and 19 heads per group for the assessment of the duration of use. Genotyping was performed by PCR-RFLP, and statistical processing was carried out using non-parametric methods (Mann - Whitney U test). Lifetime daily milk yield, milk fat and protein content, age at culling, and lifetime milking days (LMD) were analyzed. It was revealed that the AVRCYY genotype is associated with the maximum daily milk yield (22.04 kg) and the highest number of LMD (2032 days), indicating its positive influence on productive longevity. The lowest indicators were noted for the AVCCYY genotype (194 LMD). Significant differences in milk fat content were found between groups AACCYY, AARCYY, AARRYY, and AVCCYY. The AACCYY genotype showed the highest protein content (3.23%), but the lowest milk yield. Differences in the structure of culling reasons were also identified: gynecological diseases prevailed in animals with the AVCCYY genotype combination, while limb diseases prevailed in animals with the AVRCYY complex genotype. The results of the study demonstrate the significance of a comprehensive analysis of leptin gene genotypes for dairy cattle selection. The AVRCYY genotype can be recommended as a marker for increased productive longevity.