Acute disorders of purine metabolism develop in rat testes under conditions of overtraining. These disorders are characterized by enhanced catabolism and reduced reutilization of purine mononucleotides and activation of lipid peroxidation of membrane structures against the background of reduced activities of the pentose cycle and antioxidant system. Administration of D-ribose to rats subjected to overtraining improves purine reutilization, stimulates the pentose cycle work, inhibits lipid peroxidation in membrane structures of the testes, and saves the testicular incretory function.

The purpose of the research is the analysis of the range of antiparasitic drugs for pig breeding as registered in the Russian Federation and included in the State Register of Medicinal Products for Veterinary Use.The control of parasitic diseases is an essential element of veterinary support for animal husbandry, and its constituent part is the use of antiparasitic drugs. The State Register contains more than three hundred drugs to control parasitic infections of animals of various species. Forty-eight drugs are allowed for use in pig breeding. The analysis of drug compositions found that they contained a limited list of compounds as active substances. For example, 17 antiparasitic drugs contained compounds of the avermectin class as active substances (12 of them had ivermectin as the active substance); 8 drugs against endoparasites contained albendazole in their composition. At the same time, the composition of combined drugs lack distinction and is a combination of two or more active substances produced in mono-preparations. To prevent the resistance in parasites, it is advisable to use a minimum required list of drugs which allows the availability of a reserve for drug rotation in the future. Simultaneous or sequential use of different drugs (including insectoacaricides based on neonicotinoids or synthetic pyrethroids to treat premises in the presence of animals) complicates the assessment of the individual drug effect on animal health and can induce immunological stress, which creates favorable conditions for infectious diseases including opportunistic infections.

Mycotoxins can accumulate in raw materials of plant origin at different technological stages of its production. Most often, the producers of mycotoxins are fungi of the genera Aspergillus , Fusarium , Penicillium and some others. The clinical symptoms of mycotoxicoses vary significantly, and lethal outcomes are possible. For this reason, the mycotoxicological study of various types of feed under production conditions is an indispensable component of veterinary support of industrial animal husbandry. As part of this study, a retrospective analysis of the results of a mycotoxicological study of feed for different animal species was carried out in the Omsk region in 2017-2021. All feeds received by the Omsk Regional Veterinary Laboratory for 5 years for the determination of mycotoxins were examined for the presence of ochratoxin A, zearalenone, T-2 toxin, aflatoxin B 1, deoxynivalenol. It was established that almost 70 % of the studied samples contained mycotoxins, including their maximum allowable level was exceeded in 74 samples. Exceeding the permissible levels was noted for the content of T-2 toxin (34 samples), zearalenone (27 samples), ochratoxin A (6 samples), aflatoxin B 1 (4 samples) and deoxynivalenol (3 samples). The largest number of cases of contamination was recorded in the study of feed and feed mixtures. The greatest danger is the multiple contamination of feed with mycotoxins. This increases the risk of developing comorbid conditions and the spread of opportunistic infections.

The purpose of this study was to determine the nephrotoxic effect of deltamethrin in experimental animals at a dose of 43.5mg/kg (1/2 LD50). Materials and Methods: For the experiment, 48 male Wistar rats with a body weight of 240±10 g were divided into 4 groups of 12 animals each. Groups 1 and 3 were control groups, which were administered a physiological solution intragastrically. The animals in Groups 2 and 4 received a single dose (43.5 mg/kg) of the synthetic pyrethroid deltamethrin, which corresponds to 1/2 LD50. Rats were withdrawn from the experiment in two stages: 1) rats in Groups 1 and 2-one day after the deltamethrin administration; 2) rats in Groups 3 and 4-3 days after the deltamethrin administration. Biochemical and pathomorphological changes in the kidneys were evaluated. The evaluation criteria were the content of pyruvate, inorganic phosphate, and glutathione (GSH) and the activity of glutathione peroxidase activity (GPx), glutathione reductase (GR) and glutathione-S-transferase (GST) in the kidneys. Histological preparations of kidney tissue were studied. Results: The single administration of a toxic dose of deltamethrin caused a decrease in body weight of rats, an increase in kidney weight, and the accumulation of pyruvate and inorganic phosphate in the kidneys. A decrease in the GSH content was accompanied by an increase in the activity of GPx, GR and GST. One day after the experiment, in the convoluted tubules, epithelial cells with blurred contours of the boundaries were enlarged; and the granularity of the cytoplasm containing vacuoles was expressed. The nuclei of epithelial cells had different sizes; some of them were in a state of pycnosis. In the organ parenchyma, large and small blood vessels full of blood were visible. Three days after the intoxication, these symptoms became more pronounced. In the intertubular connective tissue, hemorrhages and leukocyte infiltrates were detected. Conclusion: The study confirms the nephrotoxic effect of a single toxic dose (43.5 mg/kg [1/2 LD50]) of deltamethrin. Pathomorphological changes in the kidneys are accompanied by the disturbances in energy metabolism and activation of the glutathione antioxidant system with the development of glutathione deficiency.