Preservation of the ecosystem and biological safety is closely tired with search for ways to use animal waste. Federal Law No. 248-FZ "On by-products of Animal Husbandry and on Amendments to Certain Legislative Acts of the Russian Federation" is aimed to environmental protection and for the development of agriculture and especially the sector of organic fertilization. It introduces the concept of animal by-products into the legal field and regulates the entire life cycle of these products. The law has special importance for the safety of the environment. Based on this fact we see that though it establishes strict requirements for working with by-products, the legislator makes it possible to remove a certain burden from agricultural producers and acts in a clear logic of strengthening biological safety.

Federal Law No. 209-FZ of July 24, 2009 “On hunting and on the conservation of hunting resources and on amendments to certain legislative acts of the Russian Federation” establishes the basis for regulating the number of hunting resources, which are specified by subordinate regulatory legal acts and norms of veterinary legislation.

The article discusses the requirements that determine the procedure for organizing and conducting activities to regulate the number of hunting resources, explains the essence and necessity of this activity, provides materials and research methods. Particular attention is paid to the condition of the hunting resources of the Leningrad Region and the justification for the need to regulate their numbers in accordance with regional environmental and economic needs. 

The article analyzes data on the provision of public services for licensing pharmaceutical activities in the field of circulation of medicines for veterinary use.

Studied regulatory legal documents on the procedure for licensing. The register of licensees and making appropriate changes to it is maintained by the Federal Service for Veterinary and Phytosanitary Surveillance. In accordance with the established procedure, the Service provides interested persons with information from the Register and other information in this field of activity. Through the Unified Portal of Public Services of the Federal State Information System, applications for the provision of licenses are sent. In electronic form, a request is also made to the licensing authority to amend the Register and terminate the licenses. The use of EPGU for this purpose was introduced from March 1, 2022.

The data of the North-Western Interregional Department of Rosselkhoznadzor in the assigned field of activity for granting licenses, suspension of their validity, renewal and termination of licenses are analyzed. 

For successful pharmacotherapy of animals, species identification of pathogens, analysis of antibiograms and interpretation of the results, and laboratory monitoring of the mechanisms of antibiotic resistance are important. This is necessary for veterinarians to rationally select antibacterial drugs and predict their clinical effectiveness. In veterinary clinics, antimicrobial therapy requires review of therapeutic efficacy more often than other treatments.

Klebsiella are widely distributed in nature. These microorganisms are often etiological factors in septicemia in cattle, birds, horses, pigs, as well as in the development of infectious diarrhea in young farm animals.

The purpose of the study is to study the antimicrobial resistance of Klebsiella pneumoniae isolated from dogs and its practical significance for veterinary medicine.

Materials and methods. The microorganism K. pneumoniae was isolated from wound contents in a dachshund dog. The dog was observed in the intensive care unit in the veterinary clinic.

The sensitivity to antibacterial drugs was assessed by the method of diffusion of antibiotics into agar.

Research results. In the period from 2021 to 2022, a total of 100 isolates were isolated from dogs with purulentinflammatory processes, among which 18% are gram-negative and 82% are gram-positive microorganisms, and the case of Klebsiella pneumoniae isolation is 1%.

The isolates of Klebsiella pneumonia were characterized by resistance to aminoglycosides (gentamicin, tobramycin, amikacin), III generation cephalosporins (cefotaxime, ceftriaxone, ceftazidime), IV cephalosporins (cefepime), penicillins (Amoxicillin/clavulanic acid), carbapenems (imipenem, meropenem, doripenem, ertapenem). ), fluoroquinolones (ciprofloxacin, ofloxacin, levofloxacin, moxifloxacin), aminoglycosides (gentamicin, amikacin, tobramycin) and a number of other antimicrobial drugs (sulfamethoxazole trimethoprim). Klebsiella was highly sensitive only to fosfomycin.

When analyzing this antibiogram of Klebsiella pneumoniae, it is necessary to conduct additional laboratory studies in order to establish the minimum inhibitory concentrations of antibiotics and to study the mechanisms of resistance.

Conclusion. Among strains of Klebsiella pneumoniae isolated from wound exudate in dogs, there is a spread of resistance to most antibiotics, as well as an increase in resistance to cephalosporins and carbapenems. It is necessary to carry out laboratory control of antibiotic resistance for further rational use of antibacterial drugs. 

The state of reproductive health of females determines not only their successful insemination, but also the birth of healthy viable young. However, in the conditions of livestock complexes, one often has to deal with pathologies of the reproductive tract organs, among which, recently, diseases characterized by a long latent period have become most relevant, which complicates their timely diagnosis and therapy. One of these diseases is genital mycoplasmosis of cattle. The aim of our research was to study the therapeutic efficacy of the antibiotic tulatromycin in genital mycoplasmosis in cows and its effect on the immunobiological properties of vaginal secretions. For the experiment, two groups of cows were formed, 8 heads each. The first group (experimental) – cows with a positive PCR test for Mycoplasma spp., who were treated with the antibiotic traksovet (tulatromycin) subcutaneously, at the rate of 2.5 mg per 1 kg of animal body weight, once. The second group (control) – clinically healthy cows with a negative PCR test for Mycoplasma spp. In animals, a secret was collected from the vaginal walls in which the concentration of hydrogen ions (pH), lysozyme activity, Ig G, Ig M, Ig A and sIg A content were determined. Therapeutic efficacy was evaluated by repeated PCR test 14 days after the drug application. The use of tulatromycin in a dose of 2.5 mg per 1 kg of animal body weight for the treatment of cows with genital mycoplasmosis, once leads to the elimination of the pathogen from the genital tract in 75% of sick animals, which indicates its high therapeutic efficacy. In addition, tulatromycin therapy leads to a partial normalization of the vaginal secretion reaction and its lysozyme activity, but they do not reach the level of healthy cows. The content of immunoglobulin classes in vaginal secretions under the action of the drug underwent recovery to their levels in healthy animals. 

The paper provides information about studies conducted on 490 cats, aged from 1 to 8 years, in females and males belonging to different breeds. All animals tested for infection passed the stage of clinical examination and had no contraindications to donation, and accordingly had no visible clinical signs of hemotransmissive infections (GTI). A detailed clinical examination of the patient and competent collection of anamnesis allows you to minimize the risks of detecting GTI in an animal. GTI diagnostics was performed by PCR on Bio-Rad CFX Connect Real-Time PCR Detection System and BioRad CFX 96 Real-Time PCR Detection System, ELISA – on Thermo Scientific Multiskan FC Microplate Photometer. According to the results of the study, feline immunodeficiency virus (VIC) was detected in 11 cats (2.2%), feline leukemia virus (VLC) in 5 cats (1%), hemoplasmosis (Candidatus Mycoplasma haemominutum) in 7 cats (1.4%), Bartonella henselae in 5 cats (1%). Despite the low percentage of animals in which GTI was detected, it is worth noting the need for blood banks for animals in which all potential donors undergo mandatory diagnostics. Many of the animals that turned out to be carriers of GTI had previously donated blood privately, thereby not helping recipients, but transmitting diseases to them, often incurable. Animals in contact with GTI carriers should be monitored regularly and in more depth at the GTI. Even a positive patient history and the absence of clinical signs in the animal require additional monitoring in the form of blood tests, which is very rarely carried out privately when owners donate animals as donors outside of blood banks. This fact contributes to the spread of GTI during hemotransfusion. 

The development of antibiotic resistance in microorganisms is considered a modern phenomenon, which is usually caused by empirical antibiotic therapy. One of the representatives with high antibiotic resistance is staphylococcus aureus.

Staphylococcus aureus is a pathogen resistant to broad-spectrum antibiotics and is responsible for most nosocomial infections. This microorganism synthesizes penicillinase, an enzyme that breaks down penicillin molecules. To effectively combat Staphylococcus aureus, a modified penicillin, methicillin, was previously used, the molecule of which was not destroyed by this enzyme. However, methicillin-resistant strains of this pathogen are also known today.

As part of the group of methicillin-resistant staphylococci (MRSA), there are three subgroups: nosocomial variants of MRSA, community-acquired MRSA, MRSA associated with farm animals, common among farm animals (livestockassociated MRSA, LA-MRSA). MRSA are characterized by multidrug resistance.

It was previously believed that Staphylococcus intermedius is the most dangerous staphylococcus for pets. However, over the past few years it has been found that the most common is Staphylococcus pseudintermedius, which is gaining increasing relevance. Staphylococcus pseudintermedius (MRSP) is a bacterium commonly found on the skin, mouth, nasal mucosa, and gastrointestinal tract in approximately 50% of pets. Unlike MRSA, MRSP is much more common in dogs and cats. One of the main methods of laboratory control over their spread is a monitoring study of the epizootic and epidemiological situation among animals and the population.

The home environment plays a major role in the transmission of MRSA and MRSP, therefore, by taking careful measures to prevent the spread of infection, the likelihood of infection in both companion animals and humans can be reduced.

The determination of sensitivity and resistance by phenotypic methods is carried out using: disk diffusion method, broth microdilution method, agar dilution method, E-test method.

Laboratory methods for monitoring the mechanisms of resistance of staphylococci to methicillin include phenotypic methods using disks with oxacillin, or cefoxitin.

Genotypic methods using polymerase chain reaction allow detecting the mecA, mecC gene.

For a serological diagnostic method, a latex agglutination test is used to identify MRSA and MSSA (PSB2a / PSB2 spicelin-binding protein).

Treatment of animals requires special attention because infections caused by multi-resistant staphylococci are more severe, chronic or latent, which increases the duration of treatment. 

When obtaining virus-containing material of avian metapneumovirus infection (MPVI) on Vero cell culture, special attention should be paid to the composition of growth and supporting nutrient media, since their components directly affect the proliferation and viability of the cell culture, and hence the quality of the resulting target product.

For Vero cell culture, the main nutrient medium is the DMEM medium, into which various additional components are added. It is customary to add up to 10% of fetal bovine serum (FBS) to the growth medium, as for the supporting medium, the question of the need to add blood serum of cattle (cattle) to it does not have an unambiguous solution. Since the financial costs of nutrient media have a significant impact on the cost of the final product, it is necessary to analyze the economic feasibility of using one or another component, in connection with which we have studied the role of blood serum of cattle (FBS and blood serum of adult cattle) in the technology of obtaining the MPVI virus.

As a result of the conducted studies, it was revealed that in the growth medium for Vero cell culture, it is possible to replace FBS with blood serum of adult cattle with no more than two consecutive passages. However, if the Vero cell culture is replanted more than twice, then such a replacement is impossible, since already in the 3-4 passage there are signs of a decrease in the rate of cell division and cell culture degeneration. A large number of voids and rounded cells are noted in the cell layer, which makes it impossible to use it further for the cultivation of viruses or further replanting.

It was also found that when cultivating the MPVI virus on a Vero cell culture, the DMEM maintenance medium containing 2% of cattle blood serum is optimal for use, since it ensures the production of virus-containing material with higher infectious activity compared to the DMEM medium, which does not contain or contains 10% of cattle blood serum at all. 

The article is devoted to the study of bee salmonellosis in beekeeping farms in the north-eastern regions of Azerbaijan. As a result of studies conducted in 2013-2021. in the beekeeping farms of the north-eastern regions of Azerbaijan, it has been established that salmonellosis is widespread and causes significant economic damage to beekeeping. The studies were carried out in beekeeping farms with bees of the Gonagkend population of the Bozdag Caucasian breed Aphis mellifera caucasica Gorb. 720 bee colonies were subjected to research. Infection in the Gusar region is 62.5%, in Khachmaz region - 37.5%, in Guba farms - 75.0%. Thus, in the Khachmaz region, salmonellosis infection is 37.5%, in the Gusar region - 62.5%, and in the Guba region - 75.0%. Thus, in the Khachmaz region, salmonellosis infection is 37.5%, in the Gusar region - 62.5%, and in the Guba region - 75.0%. The seasonal dynamics, the degree of spread of invasion along the altitudinal zones, depending on the strength of bee colonies, were studied. Depending on the strength of the bees, the dynamics of salmonellosis in bee colonies weakens with warming weather, that is, from March to May. So, in May, the average infection in families with poor nutrition is 18.47%, in families with average nutrition - 12.77%, in families with strong nutrition - 10.53%. The spread and development of salmonellosis is inversely proportional to the increase in ambient temperature. 

Despite the ongoing preventive measures against anthrax, in Kazakhstan, as in other countries, this disease has not been eliminated. The system of supervision and control of anthrax provides for the identification of territories unfavorable for anthrax, the causes of animal diseases.

The purpose of the study is a retrospective analysis of the anthrax outbreak in the territory of Kazakhstan in the Akmola region in 2019 to identify the causes of the outbreak, and the expected risks of its occurrence in the future, to improve veterinary and sanitary measures.

Epizootological methods were used in the work, including a comparative historical and geographical description of anthrax outbreaks in the Akmola region.

During the investigation of the outbreak, it was found that the grazing of animals was carried out on different pastures. Infection of people occurred in the village of Olginka during the forced slaughter and cutting of two heads of cattle. According to the information, in the village of Olginka, in the first days of September 2019, a bull and a cow were slaughtered. The owners are residents of the village of Olginka. A few days after the slaughter of the animals, the villagers involved in the slaughter fell ill with anthrax.

When examining the landscape of the area, it was established that there are numerous colonies of rodent burrows throughout the pasture. According to local residents, a significant increase in the number of rodents was noted in 2019.

Presumably, the infection of animals on pastures occurred due to the activation of previously unidentified anthrax burials. The removal to the surface of deep layers of soil contaminated with anthrax spores due to the presence of numerous rodent burrows in the pasture. Employees of the committee of veterinary control and supervision of the region, as well as local veterinary specialists, are recommended to vaccinate farm animals twice a year.

The article presents data showing the effectiveness of the use of anti-mastitis vaccine in breeding farms of the Sverdlovsk region, based on the study of the level of diagnosed mastitis and the indicator of somatic cells in milk. Studies have shown that the use of animal immunization against mastitis has a positive effect, so 6 months after the first vaccination of animals in the breeding reproducer and plant, the number of detected mastitis decreased by 16,6% and 7,3%, respectively, and the level of somatic cells in the milk of highly productive cows by 26,5% and 10,7%, respectively. 12 months after the first vaccination scheme was applied, the total number of animals with signs of mastitis in the breeding reproducer and plant was 13,3% and 7,5%, respectively. The level of somatic cells in the nucleus amounted to 290 thousand. /ml., and the stud farm of 450 thousand/ml 24 months after first use of vaccination schemes, the level of mastitis was identified at 6,0% and 5,7% of the studied population of high yielding cows breeding farm and breeding farm, respectively. The average number of somatic cells found in milk of animals of a farm decreased by 80 thousand/ml, the farm – to 79 thousand/ml, in comparison with the previous study period. The study revealed a significant decrease in diagnosed mastitis in animals after 32 months due to the use of the STARTVAK antimastitic vaccine, the total number of diseases in the breeding reproducer decreased by 30,6% compared to the period of the beginning of vaccination, and in the breeding plant – by 26,2%. As a result, the dynamics of reduction of subclinical and clinical mastitis in the breeder compared to the period at the time of immunization was 19,5% and 11,1%, respectively. And in the stud farm, the level of subclinical and clinical mastitis decreased by 16,9% and 9,0%, respectively. The number of somatic cells in the milk of cows contained in the breeding reproducer was 152 thousand/ml, which is 83,9% lower compared to the initial study period. The level of somatic cells in the studied samples of milk of animals kept in the breeding plant was 263 thousand/ml, which is 62,2% lower than this indicator before the application of the animal vaccination program against mastitis.

Today, farms use traditional semen and sememen divided by sex for insemination. The use of sexed sperm and the increase in the number of heifers in the offspring due to this will allow breeding enterprises: to ensure optimal parameters for entering the first calves into their own herd; refuse to acquire expensive breeding young from other farms; significantly reduce the cost of raising gobies sold for meat; reduce the number of difficult calving and reduce culling of animals for gynecological diseases; improve the economic condition of the enterprise.

The article provides the results of the use of sexed sperm in one of the farms of the Kirov region. As a result of the studies, it was found that the use of sexed semen makes it possible to significantly increase the number of calves in the obtained offspring by 2 times compared to the use of traditional seed 94.3% versus 48.2% of the use of traditional semen.

The effectiveness of the use of sexed semen is significantly higher when used on heifers: an increase of 7.5% in the effectiveness of the first insemination; a 41.9% decrease in steely animal attrition and a 0.2% decrease in abortion rates.

An essential condition for the successful use of sexed semen is the health of the herd, the qualification of an artificial insemination technician and a veterinarian. 

Evaluation of the role of corneal neovascularization is very important due to a large number of diseases and various effects of exogenous and endogenous factors inducing angiogenesis. Despite the large number of keratopathies accompanied by angiogenesis, ulcerative processes remain the most common cause of vascular growth in stroma. The variety of symptoms accompanying corneal ulcer, as well as the difference in both volume and depth of the corneal lesion dictates the need to assess the value of vascularization in ulcerative lesions of the cornea in small domestic animals. The objects of the study were 317 animals, including 157 cats and 160 dogs. The animals were admitted to the Department of Diseases of small pets of the Department of Veterinary Surgery of Moscow State Academy of Veterinarian medicine and Biotechnology – MVA named after K.I. Skryabin. All animals underwent ophthalmological examination with magnifying glass, a slit lamp, and corneal staining with sodium fluorescein to detect the diameter and depth of the defect. Ulcerative keratitis or corneal ulcer was diagnosed. The severity of the disease and its courses were established to realize the purpose of the study. The symptoms of corneal ulcers were different, including: blepharospasm, mucous, mucopurulent or purulent discharge from the conjunctival cavity, edema and hyperemia of the conjunctiva, infiltration by leukocytes at the site of the ulcer, the diameter of the lesion was from ¼ of the area of the cornea to total, the depth from damage to the multilayer squamous epithelium to a perforated ulcer, myosis, hypopion were observed from the uveal tract or a hyphae. In most cases, vascularization accompanied ulcerative processes in the cornea. It was superficial or mixed. Assessing the role of vascularization in the development of ulcerative processes in the cornea, we attach the great importance to barrier the pathological focus, preserve the integrity of the eye, as well as predict the outcome of the ulcerative process. 

The article presents the results of determining the economic efficiency of the use of two immunocorrectors — thymogen and mikovit (ribav) during castration of boars in industrial technology.

The studies were performed on 49 boars (aged 5 months), divided into seven groups — two control and five experimental ones (n=7 in each).

All animals were castrated: in the 1st control, 1st, 2nd, 3rd and 4th experimental groups — using open method; in the 2nd control and the 5th experimental groups — using closed method. Preoperative support was carried out according to the methodology used to the farm.

The boars of the experimental groups were additionally treated with immunomodulators: in the first one — with thymogen (five-day course before surgery), in the second one — with mycovit (ribav), according to the scheme of the first group with local application after surgery, in the third — according to the scheme of the first group, but after the surgery; in the 4th and 5th — only with the working solution of mikovit (ribav) according to the method of the 2nd experimental group.

The economic effect of the developed schemes was defined as the difference between the damage prevented as a result of veterinary measures and veterinary costs, taking into account the additional cost obtained by increasing the quantity of manufactured products and improving their quality. As an additional method, the total index of the effectiveness of veterinary measures was used, which was calculated by multiplying the economic damage by veterinary costs (per animal in each group) and then dividing the resulting number by their minimum multiplication.

It was shown that the inclusion of thymogen at a dose of 100 μg/cm3 into the basic regimen of intramuscular injections with a five-day course after surgery using an open castration method or irrigation of the wound surface according to the above scheme with the solution of mycovit (ribav) can significantly increase the economic effect of veterinary measures. In the conditions of industrial pig breeding (taking into account the higher manufacturability of the application), preference should be given to thymogen.

Absolutely all preclinical studies involve three groups of experiments: preclinical studies of the pharmacokinetics of the substance, including toxicokinetics, preclinical studies of the pharmacokinetics of the drug and the clinical study of pharmacokinetics on target animals. Pharmacokinetic studies of native drugs are complex because they usually involve the administration of complex components. Thus, only the use of the whole complex of pharmacognostic, chemical, spectral, physicochemical and biological methods can provide an objective assessment of the authenticity and quality of medicinal herbal raw materials and medicinal herbal preparations. The study used Wistar white rats, weight 150-160g according to the Guidelines for Evaluation of Medicinal Products (3).

The purpose of the study was to evaluate the pharmacokinetic properties of a new feed additive in the form of a premix of sorbents and phytocompositions: milk thistle (DV-silibinin, Pharmcenter VILAR CJSC), thyme (DV-timol, Akhma100). Supplements in the form of finished dosage forms were standardized for the active substance, and have a constant composition. Thus, it allowed to create a study design for a new substance in one animal species. Since the composition of the sorption component was studied earlier, the introduced substances were considered separately and in combination with sorbents.

After a single injection, the linearity of the pharmacokinetics was assessed, based on the administered different doses, the analysis of the main biochemical parameters of the blood was carried out, and the bioavailability was also calculated. Thus, the new premix based on sorbents and plant substances in the form of milk thistle and thyme does not have a negative effect on the body of laboratory animals. As a result of the studies, LD50 and LD100 were not established for the drug, the drug is classified as low-toxic, belongs to the fourth hazard class according to GOST 12.1.007-76 "Harmful substances", which allows further toxico-therapeutic tests.

This article defines fluxomics as a biomedical science and an area of metabolic research, which is used as a methodological tool for the design of medicinal substances, including for veterinary use.

The scientific novelty of the publication lies in the complexity of the ongoing review of existing research in the field of the latest methods of designing pharmaceutical substances (including those based on digital transformation), such as the study of cell flux, with a description of the main methodological approaches and principles. The main author's hypothesis of this study is the possibility of identifying the most promising approaches in terms of veterinary pharmacology for their further possible introduction into industry practice.

The purpose of the review is to substantiate the priority use of the Fluxomics methodology as a stage in the development of new drugs for veterinary use with the study of the main methodological approaches.

The information retrieval methodology was based on such general scientific methods of cognition as: a review of specialized search engines and databases of scientific and research data (Scopus, WoS, PubMed) over the past 10 years, of which the most informative ones were selected, analysis of the identified results, and their comparison by relevance.

As a result of the analysis, the role of fluxomics in the structure of "ohmic" sciences was revealed, the main concepts that determine the development of fluxomics as a set of algorithms for the study of metabolic networks, analytical and instrumental methods for implementing fluxomic models were considered, the main problems and prospects for using this methodological apparatus in the context of designing and further validation of drug candidate substances.

Due to the wide spread of babesiosis in Russia, a seasonal disease caused by protozoan blood parasites from the genus Babesia, a limited number of drugs used in its treatment, this work is devoted to determining the effectiveness of 5% imidocarb solution ("Forticarb") and 12% imidocarb solution ("Pyro-stop") with babesiosis in dogs. According to the results of the study, it can be concluded that a higher therapeutic efficacy was observed when using a 5% imidocarb solution, which is due to a lower concentration of the active substance in comparison with the second group of animals. The lower concentration of the solution used was a deterrent factor in the rapid death of Babesia canis and, accordingly, in the development of side effects as a result of the formation of a huge number of toxic decay products of both the cells of one's own body and blood parasites. The use of concomitant therapy helped to minimize side effects, stimulate hematopoiesis, provided antiinflammatory, antiallergic, hepatoprotective effects.

Animal toxicity testing is widely used in the chemical, pharmaceutical and research industries as a part of preclinical laboratory testing of substances to ensure that chemicals are safe for humans and animals. Under preclinical conditions, the safe and effective dose, acceptable dose, and exposure threshold of a substance can be established using mammals and rodents. There are enough materials on the introduction of biomodels in experiments. To summarize this knowledge, a polythematic abstract-bibliographic base was analyzed. The main attention was paid to such scientometric databases as: Web of Science Core Collection, Medline, PubMed, RSCI, as well as eLIBRARY.ru portal data for the last 10 years. An assessment of the statistical data and publication activity of the authors was made for the query modeling and ethics in veterinary medicine and medicine.

The aim of the study was to analyze modern models and prospects for using new biomodels for experiments in pharmacology and toxicology.

Having established protocols is important to ensure consistency between different studies within the same model, ensuring reproducibility and repeatability in experiments.

Based on the analysis of literature sources over the past 10 years, it can be concluded that despite the large number of regulatory framework and transgenic laboratory animals with embedded human target genes in their genome, it is not possible to obtain an identity. Probably, the main bias in predictive toxicology will be made on neural networks and computer replacement of existing biomodels. Since, despite their relative accuracy, maintenance and feeding are costly, and the field of using animals in experiments is increasingly criticized and requires new approaches.

This article describes the morphological structure of the zebrafish liver and its comparison with the organization of the liver of mammals, known methods for inducing liver pathologies in these fish, and assesses the prospects for using Danio rerio (Zebrafish) as biological models in the context of studying hepatotoxic effects.

The scientific novelty of the publication lies in the complexity of the ongoing review of existing studies in the field of using model animals to assess various hepatotoxic effects, identifying the most promising approaches from the point of view of veterinary hepatology for their further possible introduction into industry practice.

The information retrieval methodology was based on such general scientific methods of cognition as: a review of specialized search engines and databases of scientific and research data (Scopus, WoS, PubMed) over the past 10 years, of which the most informative ones were selected, analysis of the identified results, their comparison by relevance.

Summing up the results of the search, we can conclude that the results of relevant experiments indicate the promise of studying hepatotoxic effects on zebrafish, which represent a promising and cost-effective alternative to other model objects. Danio rerio can reproduce in detail and with high accuracy the patterns of occurrence, development and outcome of pathological processes in mammalian organs due to the high level of genetic preservation and similar morphology and functions of organs. It is believed that further technical development and characterization of these biomodels in the context of the study of hepatotoxicity will provide new insights into the molecular and cellular mechanisms underlying disease pathogenesis, thereby providing multiple opportunities for the identification and validation of new therapeutic targets and treatments.

The article contains an analysis of existing modern anthelmintic drugs for cattle. Trade names of drugs are divided into groups according to the active substances that make up their composition. The article discusses in detail the spectrum of action of the studied anthelmintic drugs on parasitic worms, and also displays special instructions from drug manufacturers for the use of milk and meat from animals that have been dewormed.

Even the competent use of anthelmintic drugs will not help to achieve the desired economic results from the livestock complex if the veterinary rules for keeping and feeding animals are not observed at the production site, and it is also important to correctly plan and implement all necessary veterinary and sanitary measures.

Mosquitoes are one of the most common dipteran insects and are carriers of dangerous vector-borne diseases. An important role of reservoirs of ectoparasites belongs to dogs. The domestic dog is close to the person. The problem of maintaining the health of the dog and reducing the risk of human infection in conditions of high density of blood-sucking insects can be solved by the use of repellent sprays for animals. Recently, synthetic pyrethroids have been used as effective insecticides. We have conducted clinical studies to study the effectiveness of the repellent action of the new veterinary drug "Okvet" insect-acaricidal spray on dogs. The use of the spray was carried out during the period of mosquito activity, depending on the time of day in the Republic of Armenia. The study involved 22 clinically healthy dogs aged 1.5 to 9 years of both sexes. According to the results of clinical studies, it was found that the repellent effect of the veterinary drug "Okvet" applied to dogs individually, once, while preventing bites of dipterous flying insects according to the presented doses, rules and application techniques, the drug "Okvet" showed a high efficiency of the repellent effect in the conditions of farms in Ararat area within 3 days. During the physical examination, no side effects from the use of the drug "Okvet" were revealed. 

The development steps of new drugs require consistent safety and efficacy studies in animals. This article reflects the research of a new antiseptic for veterinary dentistry containing active ingredients such as chlorhexidine bigluconate and propolis. Acute toxicity studies were carried out following the “Guidelines for the experimental (preclinical) study of new pharmacological substances” (2005), according to GOST 32644-2014 and taking into account the requirements of the Order of the Ministry of Agriculture of the Russian Federation of March 6, 2018 No. 101. rats with an average live weight of 250-280 grams, from which one experimental group of three animals was formed (for the first stage of the study), after receiving the results of the first stage, a second experimental group of three animals was formed for the second stage. The rats of the experimental groups were injected with the studied antiseptic once into the inside of the stomach using a special club-shaped needle at a dose of 2000 mg/kg. As a result of the experiment, it was found that the investigated new antiseptic containing chlorhexidine bigluconate and propolis, intended for the treatment of inflammatory processes in the oral cavity in animals, belongs to substances of hazard class V according to GOST 32644-2014. There were no deaths of animals during the experiment. 

Currently, there is a problem in satisfying livestock enterprises with cheap, highly effective disinfectants. Import substitution of the vacated market segment requires optimization of the increasing costs of livestock companies. In this regard, preclinical studies of the AKVAdez-NUK 5 disinfectant were developed and studied, in particular, indicators of acute toxicity. In the experiment, males of the Wistar breed weighing 220-230 g were used, to whom the test solution was injected intragastrically, using a pin-shaped needle, in doses of 2000, 3000, 4000 and 5500 mg/kg. Using of analytical and statistical tools in data processing allowed us to state that for the disinfectant AQUAdez-NUK 5 has followed levels for lethal doses. LD₁₆=2864,91mg/kg; LD₅₀=3676,22±347,37mg/kg; standard error for LD₅₀ is 347,37 mg/kg; LD₈₄=4585,86 mg/kg; LD₉₉=5040.69 mg/kg. The clinical picture of acute poisoning in rats was manifested by short-term excitement, followed by depression. Tachypnea, nasal discharge, impaired coordination of movement and clonic-tonic seizures were diagnosed in laboratory animals. The rats huddled in groups. The death of animals occurred due to respiratory arrest. By analyzing the results of an acute experiment and recording the frequency of animal deaths by observation days, the average time of animal death was calculated, which was 55.92 hours. Taking into consideration of the results, we can conclude increasing in the administered dose of the drug accelerates the onset of death of a laboratory animal. Up to the level of 4000 mg / kg, only one experimental rat died on the third day after the introduction of 3000 mg / kg. With the introduction of large dosages, lethality increased sharply, reaching 100% with the introduction of 5500 mg of AQUAdez‑NUC 5 per 1 kg of weight. In accordance with the classification of AQUAdez‑NUC 5, it can be attributed to drugs of an acute type of action with a moderate ability to cumulate. According to government standard 12.1.007-76, AQUAdez-NUK 5 belongs to hazard class III (moderately hazardous compounds). 

It has been established that the parasitofauna of pike and roach caught from Lake Ladoga and Lake Ilmen differ, which is determined by the significant hydrological and environmental features of these reservoirs. Parasites such as Paracoenogonimus ovatus and Ergasilus sieboldi, which are numerous in the fish of Lake Ilmen and practically absent in Lake Ladoga, can be used as biological tags to determine the reservoir from which this fish was caught. No helminth larvae dangerous to humans and animals were detected in the studied fish.

The intensive development of industrial animal husbandry and poultry farming, along with the ban on the use of antibiotics for non-medicinal purposes, requires a revision of stimulating and therapeutic and preventive approaches aimed at increasing productivity, protecting against infections and improving other production parameters, such as feed digestibility and improving the efficiency of digestion, stimulating growth and development, the quality of meat, milk, eggs. In this regard, probiotic, prebiotic and synbiotic drugs and feed additives have become widespread. Funds based on antagonistic bacteria and representatives of symbiotic microflora are actively being introduced into poultry technology, a wide domestic research experience reveals their prospects. Used mainly to maintain the balance of the intestinal microbiota, they turn out to be an effective method of combating opportunistic pathogens.

At the same time, in the countries of developed industrial poultry farming, products based on probiotic cultures have not been widely used, and a number of sources are skeptical about the ability of probiotics to influence the intestinal microbiome of poultry. This article discusses various modern studies that carry the opinions of foreign authors about the effectiveness of probiotics and their effect on the intestinal microbiome of poultry. 

The article describes the associative infection of sheep with parasitic diseases. Determining the presence of helminthic and blood-parasitic diseases was carried out in sheep farms of the Masalli region of Azerbaijan. In scatological studies in animals, infection with nematodiasis caused by the nematode Nematodirus spathiger from the Trichostrongylidae family was detected, and a clinical examination of sick and recovered sheep was also carried out. Anaplasmosis and babesiosis have been registered in sheep, the carriers of which are ticks Rhipisephalus bursa. Microscopic examination of the causative agent of anaplasmosis and babesiosis is located in the center of erythrocytes, and up to 1-4 parasites can be traced in one erythrocyte. The parasites are round and pear-shaped, 1.2-5 µm in size with a pear-shaped form and 1-1.5 µm with a round one, and there are about 20-45% of babesias in 100 fields of view of a microscope. Thus, an association of parasitic diseases - nematodirosis, babesiosis and anaplasmosis has been established in the sheep farms of the Masalli region of Azerbaijan.

The paper evaluates the effect of various vitamin preparations on the morphobiochemical composition of blood and the dynamics of body weight gain in calves. For this purpose, the first group of young animals (n=10) was injected once every 14 days four times intramuscularly with the vitamin complex "Oligovit", the second group (n=10) with 4 ml of the drug "Aquiton" in a similar mode, the third – "Asidivit" with 6 ml, the fourth group of animals was a control (without treatments). It was found that calves treated with oligovit had a decrease in the activity of alkaline phosphatase (by 27.9%; P<0.05), concentrations of inorganic phosphorus (by 14.7%; P><0.05), erythrocytes (by 27.4%; P><0.01) and hematocrit (by 26.8%; P><0.05), with an increase in the hemoglobin content in erythrocytes (by 35.2%; P><0.01). Treatment of young animals with aquiton was accompanied by a decrease in phosphorus concentration (by 25.3%; P><0.001), iron level (by 75.5%; P><0.05), hematocrit (by 23.7%; P><0.05), an increase in the calcium-phosphorus coefficient (by 22.0%; P><0.001) and the concentration of hemoglobin in the erythrocyte (29.7%; P><0.01). Treatment with asidivit contributed to a decrease in the average volume of red blood cells (by 5.8%; P><0.05) and an increase in the average concentration of hemoglobin in the>˂0.05), concentrations of inorganic phosphorus (by 14.7%; P˂0.05), erythrocytes (by 27.4%; P˂0.01) and hematocrit (by 26.8%; P˂0.05), with an increase in the hemoglobin content in erythrocytes (by 35.2%; P˂0.01). Treatment of young animals with aquiton was accompanied by a decrease in phosphorus concentration (by 25.3%; P˂0.001), iron level (by 75.5%; P˂0.05), hematocrit (by 23.7%; P˂0.05), an increase in the calcium-phosphorus coefficient (by 22.0%; P˂0.001) and the concentration of hemoglobin in the erythrocyte (29.7%; P˂0.01). Treatment with asidivit contributed to a decrease in the average volume of red blood cells (by 5.8%; P˂0.05) and an increase in the average concentration of hemoglobin in the erythrocyte (by 19.3%; P˂0.05). In the control group of animals, there was an increase in globulins (by 32.0%; P˂0.05), an increase in the concentration of hemoglobin in the erythrocyte (by 21.8%; P˂0.05), with a decrease in the level of iron in the blood serum (by 62.9%; P˂0.05). The largest weight gain was obtained in calves treated with oligovite (226.0±29.0), and the smallest in the control group of animals (171.4±27.5).

The article provides data on the study of the norms and rules of keeping and feeding dogs in kennels and at home. Cynology as a science has developed in such a way that long before various scientific theories and justifications, there was practice and experience in breeding and keeping dogs. Over the centuries, hundreds of breeds adapted to his needs have been bred by man, and assessment methods and control standards for these breeds have been formed and developed in dog breeding communities. Breeding dogs is always inextricably linked with their full feeding, maintenance and care. So, a room intended for keeping dogs must meet basic hygiene requirements, not disrupt the normal course of life processes and not reduce its resistance to various diseases. Because with the wrong methods of growing, even from the most outstanding producers, it is impossible to get high-quality viable livestock.

Goose wings are organs that serve for flying or soaring in the air, they have a powerful muscular system that needs constant blood supply. Arterial blood flows from the heart to the tissues through the arteries, which in turn are divided into arterioles to distribute blood through the tissues of the wing. On the wing of the goose there are flight feathers, without which flight would not be possible. For the growth and development of the feather, a good vascularization of the thoracic limb of this bird is also required. Knowing this, it can be assumed that the vessels going to the wing have a large diameter and a convenient skeletotopic arrangement for various veterinary manipulations during treatment and multiple preventive measures. We decided to set a goal – to study the vascularization of the shoulder and forearm on the example of a large gray goose, as well as to perform morphometry of the main arteries, to study their course and branching. The research was conducted at the Department of Animal Anatomy of the SPbGUVM. The corpses of a large gray goose in the amount of six pieces, aged from 7 to 9 months, were used as material. The corpses of the birds were delivered from a private farm in the Gatchina district of the Leningrad region. Studies of vascularization of the shoulder and forearm of a large gray goose were carried out using a complex of classical and modern research methods used in morphology. As a result of the study, it was found that the arteries of the thoracic limb of a large gray goose include the subclavian, pterygeal, axillary (axillary), scapular, brachial, which, separating, gives the radial and ulnar, deep artery of the shoulder, cranial circumference artery of the shoulder. 

The variability of branching of the coronary arteries of the heart determines the dominance of one artery over the other in the left or right coronary types of blood supply. Thus, in the left coronary type, the right coronary artery is poorly developed and vascularizes a small area of the heart, or may be completely absent. The same phenomenon, respectively, can be observed in the right-handed type with the left coronary artery. The German Shepherd is a typical representative of the leftcoronary type of blood supply to the heart, like all other representatives of its species. The aim of our study is to study the vascularization of the left half of the German Shepherd heart. To study the vascular bed of the German Shepherd heart, ten corpses of dogs of this breed were obtained at the age of two to three years after forced euthanasia. The cadaveric material was delivered from private clinics in St. Petersburg to the Department of Animal Anatomy of the St. Petersburg State University of Veterinary Medicine. The vascular bed of the heart of a German Shepherd was investigated by applying such methods as fine anatomical preparation with filling the vascular bed with latex, as well as corrosion treatment of the obtained material. As a result of the study, it was found that the source of vascularization of the left half of the heart is the left coronary artery and its main arteries, including the paraconal, subsinus, circumferential, left interventricular and left diagonal arteries. The subsinusoid artery is a branch of the left coronary artery, while the right coronary artery does not reach the region of the subsinus sulcus. The interventricular septum of the heart in a German Shepherd is completely vascularized by branches of the left coronary artery. The main artery in this case is the left interventricular artery. The results obtained confirm that the presence of a left-coronary type of blood supply to the heart in an animal does not determine that the region of the subsinus sulcus will be vascularized by the branches of the right coronary artery. 

Pskov and its region are biogeochemical provinces, since the composition of the soil of these territories is characterized by a low content of iodine and selenium. The deficiency of these trace elements will affect the composition of the feed, so it is necessary to use preparations based on selenium and iodine to prevent the appearance of symptoms of the corresponding microelementoses in cows kept in such areas. When evaluating the data obtained, a decrease in milking calcium and phosphorus in the blood serum of cows in the control group was revealed, which most likely occurred due to a lack of iodine and selenium in the normal diet of the natural cows of this farm. There is also a noticeable increase in such indicators as calcium and phosphorus in the selected samples of blood serum in both experimental groups of animals, in the diet of which two drugs were introduced: "Kayod" and "Sedimin". This haylage means a positive trend in the use of these preparations for animals.

Currently, veterinary specialists are increasingly using blood transfusion in various pathological conditions of the animal body. But at the same time, the effect of hemoconservatives on the body of animals and whole blood has been little studied. The review article provides an analysis of the results of studies of post-transfusion complications in the period from 2008 to 2022. Particular attention in these studies was paid to the frequency of occurrence, the quality of blood or its component, the compatibility of the donor and recipient, complications during and after hemotransfusion. Post-transfusion reactions that can occur as a result of blood transfusion have shown a number of possible immunological and nonimmunological reactions of the organism of animals and humans, the origin of which has been little studied. Posttransfusion reactions of the body include incompatibility reactions, reactions to erythrocyte proteins, reactions to platelets and leukocytes during plasma transfusion, anaphylactoid reactions, hypothermia, heparinization, coagulopathy and thrombosis, microbial contamination, hyperammonemia, hypophosphatemia, hyperkalemia, acidosis, pre-transfusion hemolysis, hemosiderosis. The frequency of occurrence of these reactions has not been sufficiently studied, since mainly isolated cases or studies with a small sample are described. The problem of post-transfusion reactions in animals in our country began to be studied recently. Post-transfusion reactions are practically not monitored, since this requires additional research in a hospital veterinary clinic.

Potassium is a vital element involved in ensuring the work of excitable tissues and maintaining the osmotic pressure of all body cells, therefore any of its displacements are critically important both for the diagnosis and prediction of the course of the disease, but also for monitoring treatment. In the presented study, the biochemical blood parameters of small breeds of dogs (Yorkshire Terrier, Toy Poodle, pug, Miniature Pinscher and Pomeranian), large breeds (Labrador Retriever, German Shepherd), cats (Burmese, British, Maine Coon, Russian blue, Scottish Straight and European shorthair) were analyzed. The purpose of the presented study was to identify and assess the frequency of occurrence of etiological causes leading to the development of hypokalemia in cats and dogs of different breeds in the territory of St. Petersburg with subsequent statistical processing of the results obtained. Serum levels of total protein, albumin, globulin, urea, creatinine, bilirubin, glucose, potassium, calcium, phosphorus, as well as the activity of enzymes alanine aminotransferase (AlAt), aspartate aminotransferase (AsAt) and alkaline phosphatase were determined. The parameters of hematocrit, hemoglobin, the number of erythrocytes and leukocytes were determined in the stabilized blood, also according to generally accepted methods. It was found that the most common causes of hypokalemia in cats are chronic kidney disease (41%), dysphagia as a result of dental disease (29%), neoplasms – mainly mammary glands (24%). In dogs of large and small breeds – enteropathies and conditions accompanied by vomiting (32%), blood parasites (16%) and hepatopathy (16%), with a predominance of enteropathies in dogs of both groups and blood parasitic diseases causing anemia in dogs of large breeds. It should be noted that in order to more accurately determine the diagnostic significance and the possibility of determining forecasts, it is necessary to increase the number of samples of animals with an assessment of indicators in dynamics.

The multicameral stomach of sheep of the Edilbaevsky breed, as in other ruminants, according to domestic and foreign authors, has a large number of branches of the main arterial highway, which is due to the functional feature of this organ. The main arterial highway of the multicameral stomach is the abdominal artery. The hepatic artery first departs from it, and then the right cicatricial artery branches off, which goes along the right longitudinal furrow of the scar and exits to its left surface, and the splenic artery branches off the thick right cicatricial artery, and itself in the form of a thin vessel is directed to the spleen. Further, the abdominal artery smoothly passes into the left gastric artery, which goes from the right between the scar and the mesh and, having reached the book, gives the left gastro-omentum artery to the large curvature of the rennet, and the rennet itself anastomoses with the right gastric artery on the small curvature. The methods for the study were fine anatomical dissection, vasorentgenography and computed tomography of the vascular bed with the introduction of a contrasting substance. Corpses and live individuals of sheep of the Edilbaevsky breed aged from 10 days to 14 months, from a private farm in the Leningrad region, served as material for the study. According to the results of the study, it was found that the largest increase in the diameter of the vessels of the arterial bed of the multicameral stomach in sheep of the Edilbaev breed over the entire period of research was observed in the right cicatricial artery. The diameter of other vessels vascularizing this organocomplex increases uniformly at all stages of development. We associate this fact with the active growth of this organ in the first three months of life.