The article considers the organizational and legal aspects of the fight against rabies in the Republic of Sakha (Yakutia) - a natural outbreak disease that poses a significant threat to the health of the population and animals. Taking into account the diversity of natural areas of Yakutia, where sporadic outbreaks of rabies are recorded annually, the need for strict control of the population of stray dogs is noted. The article highlights the importance of pet vaccination and information campaigns to raise citizens’ awareness. Also covered is the role of legislation, including animal registration, owner responsibilities and penalties for non-compliance with keeping regulations, which contributes to reducing the risk of infection. The conclusion highlights the importance of an integrated approach to rabies control aimed at protecting public health and preserving the region’s ecosystem.

The research is aimed at analyzing trends in the development, problems and prospects of poultry farming in the Russian Federation. The object of the study was the poultry industry of the Russian Federation from 2023 to early 2025 in the context of the current geopolitical and economic situation in the world. The main attention is paid to priority areas, namely: breeding material, veterinary drugs and feed, as well as technological support. Summarizing the data obtained, it can be concluded that industrial poultry farming, while remaining a systemforming element of food security, has maintained its basic stability in 2023-2025 due to the increasing share of the domestic Smena-9 cross and the proven breeding value of Smena lines, the expansion of domestic production of compound feeds and veterinary drugs, as well as the strengthening of national technological competencies. Domestic industrial poultry farming is actively gaining momentum in all areas of development and will soon be able to fully achieve self-sufficiency.

The article analyzes the powers of the North-West Interregional Administration of Rosselkhoznadzor to implement measures to prevent the entry into the consumer market and circulation of low-quality and dangerous food products.
During the research, we studied the regulatory legal documents that define the requirements for the quality and safety of food products in the Russian Federation. An analysis of data from the federal state information system in the field of veterinary medicine on food products was conducted. The article examines the results of food product research conducted in the testing centers of Rosselkhoznadzor within the framework of federal state veterinary supervision and border supervision when importing controlled products from foreign countries.
The data on the number of samples taken and the results of laboratory tests of samples of food products, feed and feed additives for veterinary safety for the period 2023-2024 for the subjects of St. Petersburg and the Leningrad Region were analyzed as part of safety monitoring.
The information of Rosselkhoznadzor on the implementation of powers to eliminate violations of legislative requirements in the field of food safety is considered.

Leptospirosis is a zoonotic disease that occurs worldwide and can cause a variety of symptoms that can be fatal. Bacterial spirochetes of the genus leptospira cause leptospirosis. Dogs become infected through contact with contaminated wildlife urine. Leptospira penetrate mucous membranes and cause endothelial damage in organs such as the liver and kidneys. Pathogenic leptospira persists in the kidneys of mammals and is excreted with their urine for a long time [1]. Various wild and domestic animals can act as reservoir hosts for 1 or more serotypes and can excrete the pathogen with urine for months or several years after infection [2].
The study conducted monitoring and screening studies to identify the predominant leptospirosis group in dogs. Accounting for foci and outbreaks on the territory of specific municipalities of St. Petersburg, it was found that in the period of 2023 the predominant serogroups L.icterohaemorrhagiae (197 cases), as well as L.cenoptery (24 cases), which is confirmed by high antibody titers up to 1:1600.
Analysis of associations with other serovars showed multiple antibody combinations, with L.cynopteryi being the most frequent with 17 findings, followed by l.pomona - 14, followed by L.pyrogenes - 8 findings, L.autumnalis - 4 findings, L.ballum, L.batavia and l.tarasovi - 2 findings each. L.tarasovi - 2 finds each, L.australis, as well as L.javanica 1. The data obtained indicate the need to strengthen preventive measures against leptospirosis. The use of leptospirosis vaccine provides protection against most serogroups of L.icterohaemorrhagiae, L.canicola, L.grippotyphosa, but in the territory of the Russian Federation there are no vaccines against leptospirosis infection of dogs (vaccines of Russian production), which include the following serogroups (Table 1):
L.cynoptery, L.pomona, L.pyrogenes, L.autumnalis, L.ballum, L.batavia, L.tarasovi, L.australis, L.javanica. An important aspect of this problem is to conduct and create polyvalent vaccines against leptospirosis with inclusion of the most common serogroups.

Infectious anemia of horses (INAN, swamp fever) is transmitted by vector-borne blood-sucking insects. The disease is endemic in America, in some European countries, in the Middle and Far East, South Africa, and also in Russia. There is a high risk of infection entering our country from border disadvantaged countries.The pathogen belongs to the Retroviridae family, the Lentivirinae genus. Equine INAN virus is very variable in serological and genetic terms, which makes the development of a vaccine against the disease almost impossible these days. The purpose of the work is to carry out antiepizootic measures to prevent the spread and elimination of the epizootic focus of equine infectious anemia at the Enterprise in St. Petersburg. A horse and mare born in 2020 was imported into the territory of the Russian Federation without accompanying documents and an identification number from the Republic of Belarus. The Veterinary Service of St. Petersburg was not notified about the importation of an animal into the territory of an Enterprise with cadastral number 78:14:0751301:14 in the Moskovsky district of St. Petersburg for registration. Diagnosis for INAN horses was carried out by the serological method – diffuse precipitation reaction (RDP). As a result of the competent implementation of measures provided for by the "Veterinary Rules for the implementation of preventive, diagnostic, restrictive and other measures, the establishment and lifting of quarantine and other restrictions aimed at preventing the spread and elimination of foci of infectious anemia of horses (INAN)", approved by the The Ministry of Agriculture of Russia dated 08.26.2021 No. 593, no new foci of infection of horses have been identified in St. Petersburg since 08.17.2024 to the present.

The issues of accurate and timely diagnosis of animal diseases, as well as improvement of their methods, have always been and remain relevant. They become especially important when the disease is characterized by a nonspecific clinical picture and the presence of a long latency period, which  is observed in genital mycoplasmosis of cattle. The literature review examines  the most common methods of laboratory diagnosis of this  disease, noting their advantages and disadvantages regarding their use in  industrial animal husbandry. Based on the conducted comparative analysis, the use of one or another diagnostic method is justified, based on the goals and objectives of the study. 

The actual regulatory documents regulate the content of the Enterobacter sakazakii microorganism (actual name Cronobacter sakazakii) in milk products intended for the nutrition of young children, including premature infants. We analyzed the literature data on the spread, biological properties and virulence factors of this microorganism, the current regulatory documents regulating the content of C. sakazakii in food, methods of its isolation and identification. C sakazakii is a gram–negative rod-shaped non-spore-forming facultative anaerobe, 3x1 µm, motile due to peritrichial flagella. Colonies with a diameter of 2-3 mm are formed on tryptocasein-soy agar during incubation at a temperature of 36°C for 24 hours. When incubated at 25°C, a bright yellow pigment forms on the colonies after 48 hours. Although C. sakazakii is an opportunistic microorganism, it has virulence factors and is capable of forming a biofilm with a spongy structure that adsorbs water. Thus, microorganisms are protected from drying out and are able to survive on the surface of technological equipment for a long time and be a constant factor in food contamination. C. sakazakii, when exposed to stress factors such as heating or drying, can enter a viable but uncultivable state, which significantly complicates the detection of this microorganism in food. Due to the presence of virulence factors C. sakazakii is capable of causing diseases such as meningitis, necrotizing enterocolitis and bacteremia in people with impaired immunity, newborns and premature infants. C. sakazakii is not only a medical problem, it can contaminate fertilized chicken eggs, which leads to increased mortality of embryos, hatching of weak chickens, giving low weight gain, their high mortality. It has been established that in order to return to the cultivable form of Cronobacter strains, it is necessary to have ferrioxamine E in a concentration of 150 ng/ml in enrichment media, however, the regulatory documents in force in our country do not provide for the addition of ferrioxamine E to nutrient media, which reduces the likelihood of detecting uncultivated forms of C. sakazakii in food.

Respiratory diseases in cattle remain the most common in livestock complexes. Testing for sensitivity to antimicrobial drugs using phenotypic methods is key in monitoring programmes for the early detection of resistance development and tracking trends in resistance development necessary for adjusting treatment and prevention measures in livestock farming. In the course of our research, we established the sensitivity of bronchopneumonia pathogens (Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Proteus vulgaris, Pseudomonas aeruginosa, Moraxella bovoculi, Mannheimia haemolytica) isolated from calves in livestock complexes in the Leningrad Region. The results demonstrate the insufficient effectiveness of the therapeutic measures carried out with the use of antibacterial drugs, which is associated with the resistance of a number of bronchopneumonia pathogens. Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Proteus vulgaris, and Pseudomonas aeruginosa showed phenotypic resistance to the antimicrobial drugs tested. The data obtained as a result of monitoring can be used for scientific research aimed at improving treatment and preventive measures in livestock farming.

In highly productive Holstein herds, variability in ovarian response remains a key limiting factor in the effectiveness of embryo transfer programs. It is known that the imported preparation Pluset (FSH:LH ratio of 1:1) reliably induces ovulation, whereas the domestic FSH-Super (FSH:LH ratio of 1000:1) demonstrates lower efficacy, presumably due to LH deficiency. The aim of this study was to quantitatively and qualitatively assess whether the additional administration of gonadorelin (as a source of the LH/FSH surge) can compensate for the low LH content in a standard superovulation protocol using FSH-Super in Holstein cows.
The study included 38 Holstein cows in their 2nd–3rd lactation (TPI ≥ 2590), divided into a control group (n = 17) and an experimental group (n = 21). Both groups received an 18-day protocol involving a CIDR device, four injections of FSH-Super (total dose: 1000 IU), and prostaglandin. In the experimental group, 100 µg of gonadorelin was additionally administered on day 9. Ovarian response was evaluated by the number of corpora lutea; embryo productivity was assessed based on total embryo yield, mean embryos per cow, and embryo quality.
In the experimental group, the number of corpora lutea ranged from 5 to 12 (most commonly 8–10), while in the control group the range was 3 to 8 (commonly 4–6). A total of 134 embryos were obtained in the experimental  group versus 81 in the control (a 65.4% increase); the average yield per cow was 6.4 ± 0.5 and 4.8 ± 0.4, respectively (p = 0.012). The proportion of embryos suitable for transfer did not differ significantly between groups.
Thus, the inclusion of gonadorelin in the FSH-Super protocol significantly increases quantitative indicators of superovulation without compromising embryo quality, supporting the feasibility of implementing the modified protocol in reproductive biotechnology for high-yielding dairy herds.

The article discusses issues related to the risk factors for the occurrence and development of ureteral obstruction in cats associated with ureterolithiasis. Most animals are in serious condition at the time of diagnosis, therefore, early diagnosis and prognosis of the disease prerequisites reflect the relevance of the study. The aim of the work was to establish correlations between the factors of anamnesis, occurrence and development of ureteral obstruction in cats, which makes it possible to determine a treatment and prevention strategy based on individualization of the assessment of diagnostic parameters within the framework of the identified predictors of the disease. The research methods were anamnesis analysis and clinical and instrumental examination. 565 cats were examined in 2023-2024. As a result of the analysis, a retrograde relationship was established between the selected anamnesis data and the possible causes of obstruction of the ureteral lumen. It was revealed that the pathology was mainly observed among cats that were purebred females with a history of planned surgical interventions on the reproductive organs and consuming an industrial diet. The results obtained reflected the factors influencing the formation of uroliths in vivo and the increased risk of developing the considered ureteral obstruction in cats, depending on their reproductive status, which determines this gradation of cats into the risk group for developing ureteral obstruction, making it important to carry out timely preventive treatment, which will improve the quality of veterinary care in general.

The aim of the study was to evaluate the comparative effectiveness of treatment protocols for dilated cardiomyopathy in dogs at an early stage of its development (without pronounced signs of congestive heart failure) using Pimobendan and the sulfur–containing amino acid taurine. The study involved 17 East European Shepherd dogs aged five to eight years, without regard to gender, with a diagnosis of dilated cardiomyopathy, which were randomly divided into two groups: group No. 1 "Pimobendan" (n1=9), group No. 2 "Pimobendan + Taurine" (n2=8). Pimobendan was administered at a dosage of 0.25 mg / kg body weight twice a day, taurine at a dose of 1000 mg / head twice a day. The effectiveness of the prescribed therapy was evaluated using an echocardiographic examination. The diagnosis took into account such indicators as the size of the left atrium, the diameter of the aorta, the ratio of the size of the left atrium to the aorta along the short axis, the final diastolic and systolic dimensions of the left ventricle, the final diastolic and systolic volumes of the left ventricle, the Teicholz shortening fraction and the Simpson ejection fraction of the left ventricle. It has been established that both treatment regimens for dilated cardiomyopathy are effective at the initial stage of its development. At the same time, the combined administration of Pimobendan, which belongs to the group of positive inotropes, with taurine is more effective, which primarily manifests itself in an increase in the systolic function of the myocardium and the left ventricular ejection fraction.

The paper provides results of studies on the effectiveness of treatment and prophylaxis for finger diseases in highly productive cows (11-13 thousand litres of milk per foraging cow) in two farms in Leningrad region. Due to diseases of the fingers, 12 cows selecteс in the first farm with a total of 350 animals leaving the herd, at the same time in another one. Farm -15 heads of 424 retired.
The use of pads (heels) allows to significantly increase the effectiveness of treatment of cows with extensive and deep lesions of the fingers with fused necrotic lesions, creating conditions of rest of the diseased finger, relieve pain syndrome and lameness, Prevents injury to a healthy finger. The improvement of the clinical effect of the treatment of cows allowed to reduce the duration of treatment, to prevent possible complications, to reduce the number of animals with a severe course of disease and to cull highly productive cows. It was found that in the case of minor injuries, clinical signs and lameness were not identified at the examination. Purulent necrotic processes, finger diseases were diagnosed at late stages when pronounced clinical signs appeared in the form of lameness, open abscesses and phlegmon.
The application of rubber coating of concrete floor in livestock complex has improved sanitary and hygienic conditions, since such floors make it much easier to clean them from manure, prevents it from getting between fingers, slipping animals.
The introduction of specialization of orthopedic doctor in households ensures individual approach to the treatment of animals, timely detection of surgical diseases and implementation of an adequate method of treatment and prevention. While the incidence of finger disease in cows remains at a fairly high level, with a significant reduction in the number of diseases, the number of seriously ill and culled cows.

Bone regeneration is a complex, well-organized physiological process of bone formation that can be observed during normal fracture healing and that participates in continuous remodeling throughout life. Bone has the potential for regeneration, which can best be seen by its repair after a fracture. Bone is capable of healing fractures or local defects with new tissue and regeneration without loss of high structural organization and scarring. Despite the fact that with reparative osteogenesis there are prerequisites for the complete restoration of bone structures to replace the lost ones, the percentage of complications after traumatic injuries remains quite high. This necessitates the development of new experimental and theoretical approaches to the problem of bone regeneration, including elucidating the biological mechanisms underlying the process of chemotaxis and cell differentiation in the area of traumatic injury, studying the formation of complex cellular and tissue components of the regenerate, the conditions under which this occurs, and the factors governing osteoreparation.

In modern veterinary medicine, drugs with psychotropic effects are increasingly used to correct behaviour and minimize negative effects of stress factors. The aim of the study was to investigate the effect of drugs with anxiolytic activity on the behaviour of rats and to identify the addictive potential of the drug. The experiment was conducted on male white laboratory rats of Wistar line weighing 350-450 grams. Atarax was used as an anxiolytic drug. The rats were given the drug in appropriate doses for a month. During the course of the drug administration a number of ethological tests were performed in order to reveal the effect of the active substances of the drug on the behaviour of rats. After the end of the course, ethological tests were also performed to reveal the addictive potential of the drug. The rats from the experimental and control groups showed significant differences in a number of ethological tests, which indicates the effect of the drug on the social-research behaviour of rats. At the end of the course of the drug administration in the rats of the experimental group the formation of «withdrawal syndrome» wasn’t observed. Anxiolytic drug «Atarax» has a calming effect, it is possible to use the drug in animals with increased anxiety in order to relieve their psychoemotional tension. Nevertheless, when using the drug it is necessary to accurately calculate the dosage to avoid possible toxic effect and formation of addiction.

In order to determine the effectiveness of SMOK® insect low-temperature smoke generators in poultry farming facilities at the egg factory against the red chicken mite (Dermanyssus gallinae), treatment was carried out using a different number of generators in the premises to identify the optimal dose of the active substance to combat the dermanyssus mites.
SMOKE® insect generators contain 40 g of cyflutrin, which is the main active ingredient. Four poultry farming facilities were treated, in which the presence of a red chicken mite was previously noted. All rooms had the same volume of 8000 m3. The treatment was carried out using a different number of generators to identify the optimal dose of the active substance in the fight against the parasite.
All rooms were previously treated with a mixture of ammonia (25%) and formaldehyde (40%) for the purpose of disinfection.
Rooms No. 1, 2 and 3 were treated with low-temperature smoke generators with a dose of the active substance 320, 640 and 960 g per 8000 m3, respectively. Room No. 4 served as a control room, and only ammonia and formaldehyde solutions were treated in it.
The effectiveness of deacarization was taken into account 1, 30, 90, 150, 210 and 270 days after the treatments. As a result of the effectiveness assessment in room No. 1 treated with SMOKE® insect smoke generators,
where the dose of the active substance was 320 g per 8000 m3, the recovery of the red chicken tick population began 210 days after treatment. In rooms No. 2 (dose 640 g.) and No. 3 (dose 960 g.), a red chicken mite appeared 270 days after deactivation. In room No. 4, where only ammonia and formalin solutions were treated, ectoparasites were detected 30 days later.

Single-dose acute toxicity studies are an important precursor to dose range determination trials.
The basis of any complete toxicological study of acute toxicity is the study of potential toxic effects and the establishment of maximum allowable doses for further evaluation. According to the guidelines for acute toxicity testing, the drug compound should be administered in one or more doses for a short period of time not exceeding 24 hours, and animals should be monitored for signs of toxicity for 14 days.
The purpose of our research was to study acute toxicity in rats, performed in accordance with regulatory documents. Single-dose experiments were conducted on 36 white Wistar rats. To achieve this goal, we formed 6 groups of 6 female individuals with an average body weight of 200 ± 10 g, who did not give birth and were not pregnant. In experimental animals, the test substance was administered intragastrically using a probe once in the following doses: 0.005; 0.05; 0.3; 2.0 and 5.0 g/kg of rat body weight. The control group was injected with 10% starch mucus at the rate of 1 ml per 100 g of animal. All animals were monitored, with mandatory registration of visible changes. A week after the start of the experiment, all the surviving animals were reweighed, with all the data recorded in the test report. After the experiment was completed, all the animals were subjected to humane euthanasia.
As a result of the analysis of the data obtained, the LD50 of the drug Tulamycin-AVZ when administered intragastrically to rats is 2.1625 g/ kg (2162 mg/kg) of body weight. Tulamycin-AVZ according to the classification can be classified as low-toxic compounds (Class 4).

Subchronic dermal toxicity is a characteristic that shows the negative effect of repeated repeated application of the drug for 21-28 days. The study was conducted in accordance with GOST 33216-2014 "Guidelines for the maintenance and care of laboratory animals", GOST 32642-2014 "Testing methods for the effects of chemical products on the human body. Determination of toxicity by repeated/repeated skin intake 28/21-day test". For the study, Wistar rats weighing 190-200 g were used. Control and study groups were formed, each with 10 animals. In the studied group of animals, a new medicinal product developed by us for veterinary use containing 0.1% octenidine dihydrochloride and 5% pantothenic acid was applied to a shaved skin area occupying 10% of the body area. The drug was applied to a sterile gauze cloth and attached to the skin surface for 6 hours. The study was conducted daily for 28 days. A saline solution was applied to the control group in the same way. The condition of the animals was assessed: the quality of the coat and skin, the condition of visible mucous membranes, body temperature, the state of the gastrointestinal, respiratory, nervous, and urinary systems. The animals were weighed weekly. According to the results of the experiment, there were no deaths of animals, hematological and biochemical blood parameters were unchanged, the body weight of the animals was normal during the experiment, and no changes were detected during the pathological autopsy of the animals.

Diseases of the gastrointestinal tract in animals are very common, ranging from inflammatory processes to infections and neoplasms. Gastritis, enteritis and colitis are most common. Disruption of the digestive tract occurs quickly enough, after which the pathological process covers the entire body. That is why diseases of the gastrointestinal tract in veterinary medicine require special attention, measures should be taken to find the best option for effective treatment. Gastrointestinal diseases in farm animals are still one of the main problems in veterinary medicine, which affects animal health and the economic stability of the livestock industry. According to the Rosselkhoznadzor website, the spread of gastrointestinal diseases has increased by 25% in recent years. This may be due not only to changes in housing conditions, changes in the diet of animals and stress factors. Feed includes the use of substandard feed, the same type of high-concentration feeding, when these feeds in the structure of the diet account for more than 50%. This can also include eating moldy, clogged feed, cotton husks, sunflower husks, low-quality silage, and mineral fertilizers. Stress factors include frequent redistribution of livestock, transportation, loading and unloading, high density of animal accommodation, limited mobility when kept in individual cages, and increased noise. To combat the diseases that have arisen, due to the influence of these factors, gastroprotective drugs are used. In this regard, gastroprotective drugs are becoming increasingly important in the treatment and prevention of gastrointestinal diseases. The study used health monitoring of cattle, sheep and pigs aged from 6 to 24 months. Data on clinical symptoms were collected: diarrhea and loss of appetite. Clinical trials of sucralfate and omeprazole were conducted to evaluate the effectiveness. The results showed that dyspepsia and gastritis are more common in animals. When using these drugs, it was possible to achieve a significant improvement in the condition of the animals. The data presented in this article confirmed the effectiveness of the drugs used.

At present, given the sanctions pressure, domestic poultry producers are forced to look for new, domestic high-protein feed components to maintain their productivity at a high level. One of these components may be fodder beans, which are intended for other types of farm animals. Beans of the Fanfar variety do not contain nitrites and contain nitrates in a minimal dose, the proportion of crude protein reaches 28.7%, which makes beans an indispensable high-protein component. The experiment on hybrid young chickens was conducted at the vivarium of the UO VGAVM. The first group was the control. The experimental groups were given beans at the rate of 10.0%, 20.0% and 30.0% of the combined feed. The relative increase was maximum in the 3rd and 4th experimental groups +5.7% and +6.3%, respectively. The average daily productivity in these groups was higher than in the control group – by 2.0% and 2.8%, and the relative growth rate by the end of the fattening period – by 0.2% and 0.4%, respectively. Based on the conducted research, we recommend introducing beans of the Fanfar variety into the diets of hybrid young chickens.

The aim of this study was to determine the reduction of microbial contamination of a by-product of animal husbandry – cow manure after processing in ECO biocompoters. Processing of manure in programmable electronic devices ECO, manufactured by VKO Almaz-Antey, which operate from a 380V electrical network, is a modern, environmentally friendly and cost-effective technology. Organic waste of the agro-industrial complex (crop growing, livestock farming, fish farming) is a biological threat, contributing to the reproduction of pathogenic microorganisms and the spread of zoonotic infections. Bacteria such as Salmonella spp., E.coli, Listeria monocytogenes can contaminate soil, water and crops. Biowaste also attracts synanthropic animals – carriers of infections. An effective solution is aerobic biocomposting with the participation of thermophilic microorganisms at 50–85°C. The technology ensures multi-stage degradation of the organic substrate, resulting in the formation of a bio-mixture suitable for use as a fertilizer or feed additive, with a volume of 10% of the original. In parallel, the material is disinfected with the deactivation of pathogenic microflora, including antibiotic-resistant strains.
The article is devoted to the study of the sanitary efficiency of biothermal processing of a by-product of cattle breeding - cow manure using ECO biocomposters. The method is based on the combined use of microbiological processes and temperature exposure, which ensures aerobic decomposition of organic matter by thermophilic microorganisms at 50-85 ° C. In 24 hours, the volume of waste is reduced by 90%, and the output is a bio-mixture with a high content of nutrients, suitable for use as an organic fertilizer or feed additive. The study demonstrates the high efficiency of biocomposting as a method that ensures complete elimination of pathogenic microflora: coliform bacteria, Pseudomonas aeruginosa and Enterococcus spp. The technology is based on thermophilic aerobic fermentation (50–85°C), which produces a bio-mixture that is suitable for use as an organic fertilizer or feed additive. Bacteriological analysis confirmed a decrease in the total microbial count from 15,850,000 to 28,500 CFU/g and complete elimination of target pathogens.

The aim of the study was to select optimal eluents for detecting the residual amount of organophosphorus compounds in milk using thin-layer chromatography. The research was conducted on the basis of the Department of Veterinary and Sanitary Expertise of St. Petersburg State Medical University. The research materials were solutions of malathion, chlorophos, diazinone and dimethoate. The detection of these substances in various solvent systems was carried out, followed by the calculation of the Rf mobility coefficients. The results were evaluated in the rays of UV light using UV cabinet UVK-HDi. As a result, the most sensitive eluent systems were identified: hexane–acetone 5:1 for diazinone and dimethoate, hexane–acetone 1:1 for chlorophos, and chloroform for malathion. The use of these systems makes it possible to isolate a substance and detect it using our proposed methodology.

As part of the experimental work, three groups of animals with varying degrees of Holstein were formed. The first group was characterized by blood content of 25...50% (n=15), the second – 51...75% (n=30), the third – 76...91% (n=15). It was found that cows with a Holstein level of over 75% had a 7.5% lower total protein level in their blood compared with animals with a blood content of less than 50% (P < 0.05). At the same time, in animals with a blood content of 25...50%, the concentration of triglycerides was 10.0% higher than in individuals with a higher degree of Holstein (P<0.05). AST in cows with a blood content of 50...75% was characterized by 19.9% (P<0.05) higher activity compared with less blood genotypes. In the first group, a significant number of cows had hyperproteinemia (33.4%), while the optimal ratio of protein fractions was found only in animals with a high degree of Holstein. The frequency of hypercholesterolemia ranged from 43.3% to 60%, ketonemia – from 20% to 40%, hyper- and hypoglycemia – from 6.6% to 13.3%, and hyperphosphatemia was found in almost all animals. The largest number of cows with increased AST activity was present in the second group, whereas in animals with less or more blood, this pathology was 2.0...2.7 times less common (P<0.05).

The bones of the cerebral part of the skull form the cranial cavity, which is a container for the brain, its membranes, vessels and venous sinuses. Most morphometric studies of the dog skull focus on comparing the facial and cerebral divisions in different breeds, their classification and general structural analysis, without a detailed study of the parameters of the cranial cavity [5-7]. The purpose of this study is to conduct a morphometric analysis of the cranial cavity in dogs of mesocephalic breeds. Computed tomography was chosen as the main research method. The group of dogs for the study included Beagle, Yorkshire Terrier, Akita, and Mestizo dogs weighing up to 7 kg. To conduct the study, the dogs were divided into two groups. The first group included animals with a total skull length of 15 to 19 cm (beagle, akita). The second group includes animals with a skull length of 11 to 14 cm (mestizos weighing up to 7 kg, Yorkshire Terrier). The CT scan and craniometry were decrypted using the RadiAnt computer program. During morphometry, the parameters of the maximum width, height and length of the cranial cavity, similar parameters of the cerebral part of the skull, as well as the zygomatic width and total length of the skull were determined. In the course of the study, a morphometric analysis of the absolute and relative morphometric parameters of the cerebral skull and cranial cavity of dogs with mesocephalic type of skull was carried out. It was found that in dogs of the first group, the cranial index is 56, and the maximum difference in the parameters of the cerebral skull and cranial cavity is in length, the smallest in width. For dogs of the second group, the cranial index is 61, and the length parameters have the greatest difference, as in the first group, but this difference is less pronounced. The indices of the cerebral skull and cranial cavity are higher in dogs of the second group, which indicates the anatomical features of the skull structure and its general shape, as well as the degree of development of the masticatory muscles. The ratio of the length of the cerebral skull to the total length of the skull in both groups turned out to be similar, which indicates the dependence of the cranial index mainly on the size of the facial region.

The muscular system of pigs plays a key role not only in providing movement and maintaining body tone, but also closely interacts with the venous system, ensuring effective blood flow to the heart. Pigs have developed collateral venous networks around joints and muscles that provide backup blood flow when major vessels are squeezed during lying down or intense movements. Knowledge of the features of the venous vessels of the hip joint and the ways of blood outflow from various muscle areas is used in surgical practice, as well as in clinical pharmacology when choosing sites for intramuscular injections of drugs. The aim of the study was to study the anatomical features of the hip joint muscles and determine the topographic location of the veins associated with them in Yorkshire pigs. The study was conducted at the Department of Animal Anatomy of the St. Petersburg State University of Veterinary Medicine. The study used newborn piglets for 28-30 days of the postnatal period of ontogenesis. The study was conducted on 10 pelvic limbs obtained from five Yorkshire pigs. Traditional morphological research methods were used, namely: fine anatomical dissection, photographing, and vasorentgenography. Thus, the study established the anatomical features of the hip joint muscles and determined the location of the veins associated with them in Yorkshire pigs. The morphology of the venous collectors of the muscles of the hip joint is directly dependent on the structure of each individual muscle, its functional load and the general dynamics of the tissues of this area of the limb. These features reflect the evolutionary adaptation of the venous system to the biomechanics of muscles, providing a balance between flexibility and stability of blood flow. The study of this system acquires practical significance not only for veterinary medicine and animal husbandry, for example, in the treatment of pathologies of the musculoskeletal system in pigs, but also for biomedical research.

The aim of the study was to establish the features of the clinical and morphological manifestation of nephrosclerosis in cattle. The object of lifetime and postmortem research was a Holstein black-and-white breeding bull at the age of two years. Blood and urine samples served as the material for laboratory studies. After forced slaughter, the bull was subjected to a pathological examination, with sampling of renal tissue for its pathohistological examination. The selected material was fixed in a 10.0% solution of neutral formalin. Then it was poured into paraffin according to the generally accepted method. Sections 5-7 microns thick were made from the obtained paraffin blocks, which were stained with hematoxylin and eosin. It has been established that the clinical picture of nephrosclerosis in cattle includes a variety of nonspecific clinical signs. It should be noted that this disease is most characterized by proteinuria, associated with a decrease in urine density, as well as anemia, manifested by a decrease in the number of red blood cells and hemoglobin levels. Among the biochemical abnormalities, it should be noted a significant increase in serum levels of urea, creatinine and phosphorus, which indicates renal failure, as well as increased activity of ALT and AST, which indicates damage to the liver and heart muscle. An autopsy reveals changes characteristic of bilateral chronic interstitial nephritis at the stage of sclerosis and atrophy of the parenchyma, catarrhal erosive abomasitis, catarrhal enteritis, cloudy swelling (granular dystrophy) of the liver, pulmonary edema and "asphyxiated heart", which is characteristic of acute systemic intoxication. At the microscopic level, extensive areas of renal tissue atrophy are detected in the kidneys, as well as significant inflammatory proliferates consisting of lymphocytes, macrophages, fibroblasts, and collagen fibers.

The muscular system plays one of the main roles in the vital activity of fur-bearing animals. It determines their ability not only to survive in their natural habitats, but also to adapt to the conditions of cellular maintenance, which reflect limitations in motor activity. Of particular importance in the formation of the musculoskeletal system of the thoracic limb are the muscles of the elbow joint, which are responsible for flexion and extension of the thoracic limbs, providing stability during movement, maneuverability and thrust during motor mobility. These muscles are not only involved in complex motor acts, but also support the structural integrity of the joints, distributing the load, which can further prevent injury. However, in animal farms, the natural needs of sables are suppressed due to the limited space of cells, which lack sufficient space for activity or the use of simulated natural objects. This leads to physical inactivity, provoking skeletal muscle atrophy, especially in the extremities. Males of the black Pushkin sable breed aged 36-40 months of postnatal ontogenesis, weighing 1250-1300 g in the amount of 10 individuals, were selected as the object of the study. Classical research methods were used, such as fine anatomical dissection, morphometry, and photographing. Based on the studies of the topography of the muscles of the elbow joint of the black Pushkin sable, it was concluded that the elbow joint is biaxial in function with developed muscles. Its mass exceeds a similar indicator in the shoulder area by 1.27 times, this determines the functions of the elbow joint with a predominance of flexion and extension, while the extensor muscles of the joint (triceps, ulnar, fascia tensor of the forearm) prevail over the flexor muscles. Therefore, the main function of the joint during locomotion is extension. Moreover, the supinators and pronators of the muscles of the same name are extinguished, and the thoracic limb of these animals acquires a confident forward movement.

The article presents the results of a comparative study of red blood indices in adult tigers, leopards and domestic cats. Similarities in quantitative blood indices were found in leopards and domestic cats, with no statistically significant differences. Tiger red blood indices differ significantly from those in leopards and cats. The greatest difference is in the average concentration of hemoglobin in erythrocytes, which is significantly higher in tigers by 28.7% than in leopards and by 37.2% than in cats. They also have a significant predominance of corpuscular volume – by 24.6-27.6% compared to other animals studied. The difference in hematocrit is smoothed out due to the lower concentration of erythrocytes in tigers. For this reason, no significant differences are observed when comparing the MCHC index, which is higher in tigers than in leopards by 3.1% and in cats by 7.9%. Tigers have been found to have higher concentrations of red blood cells - by 13.7-14.1% and hemoglobin - by 11.4-18.0%. All the differences found indicate the influence of species anatomical and physiological characteristics on the quantitative and qualitative parameters of red blood, as well as the development of adaptive functions in tigers, allowing them to maintain extraordinary physical strength and endurance under increased loads. Leopards have developed an adaptive skill of saving energy resources. Cats do not spend as much energy on their life support as wild cats, due to the availability of food on a permanent basis.

The presented work provides an overview of the activities of veterinary institutions and veterinary scientists in the study of epizootology, pathogenesis, etiology and biology of pathogen development and the development of measures to combat and prevent the most common and most dangerous infectious and invasive diseases of reindeer. The contribution of veterinary researchers and specialists in the development of veterinary infectology and parasitology in the Far North in ensuring the epizootic well-being of the northern regions is shown. The purpose of the presented article, first of all, is to show that despite the difficult climatic (extremely low temperatures) and organizational (pasture system of reindeer herding far from populated areas) difficulties, extremely necessary research was carried out to find means to combat infections and invasions in the Arctic zone of the Russian Federation.