We studied the biological properties of the myxomatosis virus Mixo/ARRIAH-18 strain in cultivated on a transplantable RK-13. The cell culture was grown as a monolayer on tissue culture flasks. The aim of the research was to standardize the conditions for obtaining the virus and evaluate its immunological effect on the animals. According to the known number of cells that make up the monolayer in the mattress (E = 1.885 × 10⁶), the volume of the nutrient medium (V, cm³), the given doses of the virus, TCI₅₀ (D) and the multiplicity of infection per cell (C = D/E, TCI₅₀/cell. ), we determined the indicators characterizing the reproduction of the virus in this culture: the time of development of CPE ≥ 75 % (L, hours); infectious titer in culture fluid, TCD₅₀/cm³ (T); virus reproduction coeffcient (lg K = lg T + lg V - lg E, lg TCD₅₀/cell). As a result of the studies, it was found that effective reproduction of the vaccine virus in the RK-13 cell culture will occur at a multiplicity of infection of at least 0.017 TCD₅₀/cell. In this case, the defeat of at least 75 % of the cells should be detected on average within no more than 19.33 hours, which will lead to the accumulation of the pathogen in the culture fluid in a titer of at least 6.33 lg TCD₅₀/cm³. As experimental animals, rabbits of 45 days of age, not immune to myxomatosis, were used. The immunological effect of vaccinating rabbits with the studied strain, the assessment of which corresponds to the neutralization index adopted in GOST 28086 (lg IN = 3.0), was achieved using an immunizing dose of D ≈ 4.0 lg TCD₅₀. According to the results of IFA, the neutralization index lg IN = 3.0 corresponded to the assessment of the average logarithmic titer of antibodies lg Ts = 3.138 ± 0.105 or, according to the lower limit of the confidence interval (p ≈ 0.05), lg Ts - 2S = 3.138 - 0.210 = 2.928, which corresponds to the value Ts = 847.

Fishing is one of the most common hobbies among people and very often caught fish is eaten or used as pet food, not considering that it can become a source of invasion, as it is an intermediate host in the development cycle of a large number of parasites. Therefore, the aim of the work was to conduct a parasitological study of various species of fish caught in the Nizhnekamsk reservoir in the channel of the Izh River in the Alnashsky district and coprological research of samples from carnivorous animals (cats), for which the fish is used as feed in its raw form. Five species of fish (catfish, perch, pike, soroga and bream) were subjected to research. An external examination was carried out, the state of the abdominal organs was assessed, the muscles under the compressorium were examined, and the extent of invasion was determined at different times of the year. We have found metacercariae of the causative agent of opisthorchiasis, paracenogonymosis and postdiplostomatosis. The greatest extent of invasion is observed in winter, but in relation to infection with opisthorchiasis, the extent of invasion of cyprinids, on the contrary, is the highest in summer. We associate such a difference in indicators with the peculiarities of the helminth development cycle, since Opisthorchum felineus develops in carnivores and humans to the sexually mature stage, and Posthodiplostomum cuticola and Paracaenogonimum ovatus - in fish-eating birds.

Parasitoses are widespread in ruminants. Among other pathologies in the conditions of the Caspian lowland, where helminthiases dominate. Their cause 63 types of pathogens, among which fascioliasis, dicroceliasis, echinococcosis, monieziosis and strongylatoses are often recorded. Almost always, helminthiases occur in mixed invasions, the invasion extensiveness (EI) reaches 84.0 %, with an invasion intensity (II) of 5-3240 ind. A feature of the epizootology of animal helminthiases in the territory of the Caspian Lowland is the duration of the warm period of the year up to 210-220 days, when + (10-12) °С is often observed in December and January, and the active state of the invasive stage of pathogens in the external environment and infection associated with this livestock. With intense damage to organs (liver, lungs, intestines), sick animals experience large «parasitic loads», often with irreversible pathological changes that are incompatible with life. Often in mixed invasions, from 4 to 17 types of pathogens are recorded. In the region, a hard epizootic situation is created annually for the most dangerous helminthiases, which cause great damage to livestock. Powerful stably functioning foci have formed in biotopes, which are constantly are seeded with an invasive beginning through the source of invasion (infected animals) throughout the year. Therefore, it is necessary at the end of summer and autumn to carry out diagnostic studies on helminthiases of animals by lifetime coprological, postmortem autopsies of sick cattle. In October, to conduct planned coprological research of 10 % of the livestock for helminthiases and preventive deworming of all animals with broad-spectrum dosage forms. In addition, it is necessary to carry out pasture prevention and land reclamation throughout the year

The article is devoted to the study of the epizootological circulation of echinococcosis in dogs and goats with an assessment of the fertility of Echinococcus granulosus larvocysts in goats of different ages in Karachay-Cherkesia. It was established that populations of farmer dogs in the arid subzone of Karachay-Cherkesia were infected with echinococcosis with an index of occurrence of zoonotic invasion of 58.3 %. In the plain zone, EI of zoonosis consists of 75.0 %. In the foothill zone, the EI of echinococcosis of the dogs living on folds was the highest and amounted 92.3 %. In the mountainous zone, 80.0 % of the examined dogs were infected with echinococcosis. On average, in Karachay-Cherkesia, with different indicators of the pathogen abundance index, 78.8 % of farmer dogs were infected with Echinococcus granulosus cestode. These data confirm the growing epizootological danger of helminth in the region. This is indicated by the fact that in the climatic zones of Karachay-Cherkesia, 18.0-37.0 % of domestic goats (on average, 28.0 %) were infected with cystic echinococcosis. In adult goat populations, as a result of the accumulation of cysts, quantitative indicators of the invasion abundance index, fertility and biopotential of Echinococcus granulosus larvocysts were high and ranged from 6.9 to 20.3 ind./animal. In the fiuid of echinococcal cysts microscopically in 1 ml, 0.5-2.1 thousand protoscolexes of E. granulosus were determined. In the natural and climatic zones of the Karachay-Cherkess Republic, the main reasons for the prevalence of socially dangerous zoonosis are non-compliance with the deadlines for deworming dogs, ignoring measures for veterinary supervision and sanitary and hygienic education of the population.

The article discusses some features of the biology and ecology of E. granulosus in the conditions of the plains of Dagestan. Our studies and experiments have made it possible to understand that eggs of E. granulosus, which are under water, can maintain their infectivity on the level in 16-18 percent, 7-8 percent and 0 % after 6 months, a 1 year and 1,5 years, respectively. The survival rate of E. granulosus eggs after being under the plant substrate after 6 months was from 28 to 30 percent, after 1 year it was from 15 to 16 percent, after 1,5 years it decreased from 2 to 4 percent. The all eggs died after two years. Under the sun, the eggs also retain their invasiveness. It is equal to 2 to 4 percent after 3 months. And after 6 months, it can be equal to 0. Prepatent period of E. granulosus in puppies in the summer is from 80 to 90 days. This time is enough for the animal to become infected and helminths capable of laying eggs develop in its organs. Between 20 and 44 adults of E. granulosus have been found in the intestines of adult dogs (20, 31, 38 and 44). This is 37.5 %, 28.0 %, 29.7 %, 27.9 % less than the puppies. Research was also carried out in winter. The autopsy to detect 15, 26, 30, 37 specimens of adults of the hydatid worm (E. granulosus) in the intestines of puppies. This experience allows us to conclude that in the winter season, the prepatent period of E. granulosus increases by 6-9 days. The number of helminths decreases from 54.5 to 39.6 %.

The results of a biochemical blood test on the 20th and 40th day after infection of the Diphyllobothrium latum had a little changes in some indicators, which in general did not have significant diagnostic significance. A decrease in the level of vitamins is noted in dogs infected with a broad tapeworm on the 20th and 40th day after the invasion. In all cases, a more pronounced decrease in vitamin levels (A, E, C) depended on the timing of observation of infected dogs. The lowest levels of vitamins A, E, C are noted on the 40th day after the invasion and amounted to: vitamin E - 23 %, vitamin A - 17.2 %, vitamin C - 27.3 %. Despite the general dynamics of the decrease in vitamins levels (A, E, C) in infected dogs with broad tapeworm, this decrease was more pronounced when monitoring the content of vitamin C in contrast to the rest. On the 20th day of the invasion, an increase in the level of enterokinase is noted, in contrast to the indicators of the control group. In the study of enterokinase on the 40th day of infection, the enterokinase index continued to increase and amounted to 12 ± 0.24. A marked increase in the enterokinase index in dogs infected by Diphyllobothrium latum will signal the suppression of secretory activity of the intestine.

The paper presents a comparative description of the block methods of the brachial plexus in dogs under the control of neurostimulation and sonography. It should be noted that during conduction anesthesia using ultrasound scanning, the problem of constant and long-term visualization of the needle position remains. At the same time, in order to reduce the subjective factor, a method of electrical nerve stimulation was developed, which allows "to find” target nerves by visualizing the motor responses of muscles until the injection of local anesthetics. To confirm the identification of the nerve plexus structures, we used 2 methods: ultrasound leveling for group 1 and double control - ultrasound leveling and electrical stimulation - for the 2nd group. The study involved 28 dogs. The effectiveness of the development of a complete blockade was evaluated based on changes in hemodynamics and respiratory changes in response to a deep pain sensitivity test on each finger of the anesthetized limb. As a result of our study, the double control method showed the most diagnostic accuracy in identifying all the nerve structures of the brachial plexus and amounted to 100 %. In the ultrasound-guided group, the effectiveness of surgical anesthesia was lower and amounted to 86 % for blockade of the brachial plexus by axillary access and 72 % for the paravertebral cervical method.

Currently, mastitis of infectious etiology remains a significant problem for dairy farming, which are widespread and cause enormous economic damage. The frequency of occurrence of mastitis by months during the year varies from 1.9 to 7.7 %. In general, 33.1 % of cows get sick by mastitis during the year. Staphylococcus aureus, Streptococcus zooepidemicus, Streptococcus dysgalactiae are isolated from the milk of cows cows suffering from mastitis. Streptococci have such virulence factors as a capsule, fimbriae (M-proteins), toxins, enzymes. Staphylococci are able to form a microcapsule and biofilm, adhesins, enzymes, toxins, etc. Prevention of mastitis should consist of a complex of veterinary, sanitary and zoohygienic measures. As part of a study on the specific prevention of mastitis in dairy cows, an associated strepto-staphylococcal vaccine was tested. According to serological studies in indirect hemagglutination reaction and diffuse precipitation reaction, after double immunization of cows the suffcient titers of antibodies to staphylococcal and streptococcal antigens were developed (diagnostic titer is 1:40) to create specific immunity. The maximum increase in titer antibodies is noted by the 28th and 48th days of the study, respectively. Serum bactericidal activity and serum lysozyme activity indicators also acquired initial values by day 48. The results obtained provide grounds for further study and use of an experimental vaccine for cows.

The work aimed to conduct a comparative analysis of clinical and hematological parameters in dogs and domestic cats with multiple organ pathology with primary liver damage (hepatic-renal syndrome) and primary kidney damage (renal-hepatic syndrome). The research carried out in veterinary clinics of Lugansk city. The authors found that regardless of the initial stage (kidney or liver) of polymorbid pathology in dogs and domestic cats, there is no significant difference between erythro- and leukocytopoiesis systems in experimental animals. The disease symptomatology does not allow differentiating variants of multiple organ pathology in dogs and cats both. At the same time, the ultrasound picture of the hepatic-renal syndrome characterized by the development of dystrophic changes and cirrhosis with foci of regeneration in the liver, signs of glomerulonephritis and nephrosclerosis in the kidneys. The same time in renal-hepatic syndrome, the development of acute tubular necrosis and interstitial nephritis was noted, nephrosclerosis in severe cases against the background of heterogeneous echogenicity of liver parenchyma and filling of the gallbladder. The hepatic-renal syndrome accompanied by pronounced cytolysis, hepatocellular insuficiency, cholestasis, hyperazotemia (an increase in urea by 1.5 and creatinine by 1.9 times) against the background of the absence of a significant interspecific difference between the levels of biochemical parameters in blood serum. Hyperfermentemia of AlAT and AsAT (2.7 and 1.8 times) was accompanied by creatininemia in cats and bilirubinemia in dogs.

The aim of the study was to study the features of the histological structure of the kidneys in sheep of the South Ural breed in the postnatal period of ontogenesis. The studies were carried out on the Department of Morphology of Physiology and Pathology of the Orenburg State Agrarian University. The material for the study was the kidneys of the South Ural breed sheep from 12 individuals of both sexes. Animals were divided into 2 age groups based on the classification of development periods. For histological examination, we took the material no later than two to three hours from the moment of slaughter of the animal. Pieces of tissue were fixed in a 10% solution of neutral formalin. After fixing and sealing, the pieces were poured into parafin. Histological sections 5-7 µm thick were stained with hematoxylin-eosin. On histological preparations, we determined the thickness of the connective tissue capsule, the cortex and the medullary layer, the diameter of superficial, intracortical and juxtamedullary nephrons, as well as the diameter of the vessels of the microvasculature of the kidneys. Morphometric parameters were obtained using a screw eyepiece-micrometer MOV-1-15x (GOST 15150-69) and an eyepiece ruler, followed by statistical processing of quantitative parameters of histological structures. In our study of histological preparations of the kidneys of day-old lambs, an organotypic morphology was revealed. Outside, the kidney is covered with a connective tissue capsule 42.5 ± 4.28 µm thick. The boundaries of the cortical and cerebral zones are clearly differentiated, in the cortical zone (thickness - 1575.0 ± 71.11 microns), numerous compact subcapsular and juxtamedullary renal corpuscles - glomeruli, proximal and distal convoluted tubules, as well as connective tissue trabeculae were visualized

In the course of reintroduction work, it is necessary to ensure the epizootic safety of not only representatives of the restored species, but also the existing biocenosis of the area. The goal of the project is to reduce epizootic risks during the reintroduction of the Persian leopard (Panthera pardus ciscaucasica) in the North Caucasus. To achieve this goal, it is necessary to assess the presence and prevalence of diseases dangerous for leopards in the emerging range of the species in the region, and take measures to reduce epizootic risks. In accordance with this, it is necessary to perform the following problems: to perform an epizootological investigation of natural biocenoses in potentially suitable leopard habitats in the North Caucasus; to realize an analysis of epizootic risks for the reintroduction of the leopard based on the results of the investigation; based on the risk analysis, to determine the need and list of protective and preventive measures in preparing animals for release. The tables reffect the diseases characteristic of the North Caucasus, to which leopards are susceptible. A scheme for studying the components of the biocenosis for the presence of these diseases (natural foci, pathogen animal reservoirs, transfer of pathogen) is given. The low population size of leopards (only a few animals in the North Caucasus), taking into account the characteristics of the biology of the species, suggests extremely rare contacts between animals. Of the other cat species in the mountains and foothills of the North Caucasus, only the Caucasian lynx and the Forest cat live, the number of which is also not big. Thus, when analyzing epizootic risks, most attention should be paid to natural focal vector diseases common to several animal species. These diseases can cause the greatest harm to the new leopard population. The proportion of species-specific feline diseases under these conditions will be less significant.