Значне розширення масштабів синтезу і застосування у сільському господарстві різних небезпечних хімічних сполук спричинює щоденний небезпечний вплив на організм комах, тварин і, безперечно, людини. Саме тому виникає потреба у контролі за поширенням токсикантів хімічної і біологічної природи у тваринництві і довкіллі. Нами проведено аналіз поширення токсикантів у тваринництві і довкіллі шляхом хіміко-токсикологічного аналізу кормів, посліду, крові, внутрішніх органів, умісту шлунку загиблих від отруєння тварин, а також загиблих бджіл, ґрунту, зеленої маси і продуктів бджільництва. У роботі застосовувалися сучасні методи досліджень. Уміст важких металів визначено методом атомно-абсорбційної спектрометрії, пестицидів – методом газової хроматографії і рідинної хромато-мас-спектрометрії, мікотоксинів – методом високоефективної рідинної хроматографії, імуноферментного аналізу і тонкошарової хроматографії. Ізоніазид досліджено у шлунку собак методом рідинної хроматографії із мас-спектрометричним детектором. Аналіз складу важких металів у біологічному матеріалі загиблих тварин показав, що частіше зустрічаються харчові отруєння їх миш’яком. Окрім того, зареєстровано значну частку отруєнь собак ізоніазидом. Установлено, що продукти бджільництва досить часто контамінуються пестицидами. Досліджено, що кукурудза, порівняно з іншими злаковими, частіше вражається мікроміцетами роду Aspergillus flavus і Fusarium. У кормах найчастіше виявлялися такі мікотоксини, як дезоксиніваленол, Т‑2 токсин і зеараленон, рідше – афлатоксини. Таким чином, токсичне навантаження на екосистему призводить до порушення безпеки харчового ланцюга і зниження ефективності виробництва продукції тваринництва. Контамінація токсикантами кормів, а також медоносних рослин становить загрозу не тільки для сільськогосподарських тварин і корисних комах, але і для споживачів тваринницької продукції. Тому на національному і міжнародному рівнях дуже важливим є здійснення ефективного контролю за виробництвом та імпортом безпечних кормів і харчових продуктів.

The article presents the results of research on the determination of mercury in fish muscles and seafood, conducted based on the State Research Institute for Laboratory Diagnostics and Veterinary-Sanitary Examination by the Atomic Absorption Spectrometry Laboratory as systematic research in the period from 2019 to 2021. Mercury content in fish muscles was determined by atomic absorption spectrometry with direct sample injection. The study was carried out using a Milestone DMA-80 atomic absorption spectrophotometer (Italy). Certified standard samples (MERK) of mercury ion solution composition with an accredited value of 1.0 mg/cm2 were used to construct the calibration curves. The detection limits of mercury in fish and seafood are determined according to the validation data: the LOD detection limit is 0.1 μg/kg, and the LOQ detection limit is 5.0 μg/kg. During the studied period, research was carried out on 3368 samples of fish products: 2587 samples of sea fish, 161 samples of freshwater fish, 130 samples of other types of fish and seafood – 490 pieces, of which four examples of sea fish, namely fish of the tuna family, were found to exceed the maximum permissible level of mercury, which is 0.12% of the total number of studied samples. The mercury content in tuna muscles ranged from 0.356 to 1.889 mg/kg, 1.8 times higher than the MDR. It was found that the average mercury content in the muscles of freshwater fish was 0.006–0.315 mg/kg, which is significantly lower than the average mercury concentration in marine fish. The mercury concentration in the muscles of other types of fish and seafood was 0.008–0.472 mg/kg and did not exceed the regulated norms.

One of the most actual problems of modern poultry farming is to increase the preservation of chickens and ensure high intensity of their growth at all stages of rearing. The development of alternative methods of prevention and treatment of infectious diseases of poultry involves the use of preparations of natural or organic origin, which have antagonistic properties against infectious agents and are able to balance the immune response. A prominent place in the system of disease prevention and increasing the resistance of animals and poultry is the development of modern probiotic and bactericidal preparations. In view of this, we studied the influence of the synbiotic preparations “Biomagn” in combination with the disinfectant “Diolide” on the state of the T- and B-cell links of the specific immunity of broiler chickens during the period of their rearing. The preparation “Biomagn” is based on representatives of the normal commensal microflora - non-pathogenic lactic acid bacteria with antibacterial and immunomodulatory properties and additional components: magnesium chloride, chitosan, xylanase, protease, cellulase, milk thistle meal, acidity regulator, betaine and emulsifier. The specified remedy is used to ensure optimal level of metabolism, increase immune function, growth, safety of animals and poultry. The results of the research showed that the use of the synbiotic preparation “Biomagn” in combination with the disinfectant “Diolide” had a positive influence on the activity of T- and B-cell links of specific defense of broiler chickens organism during the period of their rearing. This is evidenced by an increase in the amount of T-lymphocytes (total, active and theophylline-resistant) and B-lymphocytes in the blood and an increase in their functional activity due to the redistribution of the receptor apparatus of immunocompetent cells. In particular, a decrease in the number of functionally inactive T- and B-lymphocytes in the blood and an increase in the number of cells with low and medium degree of avidity. Therefore, the use of a set of studied immunotropic preparations is a promising direction in increasing the resistance and productivity of poultry. This allows in industrial conditions of maintenance, without loss of productivity, to respond to technological factors that can lead to immunodeficiency, disease and death of poultry.

A liquid chromatographic-tandem mass spectrometric (LC–MS/MS) multi-residue method has been used for the simultaneous quantification and identification of 9 residues and metabolites of benzimidazole derivatives that the most widely used as anthelmintic veterinary drugs of animals. The modified QuEChERS method was used for sample preparation, which was initially developed for pesticide residue analysis. This paper highlights how quick, easy, cheap, effective and rugged the QuEChERS extraction method is. The method was successfully validated according to the 2002/657/EC guidelines. Recovery of analytes was in the range 99 – 110 %. The decission limits (ССα ) were calculated at MRL level for analytes with an established permitted limit as next: 104.5 μg kg-1 (albendazole), 53.2 μg kg-1 (fenbendazole), 54.2 μg kg-1 (flubendazole), 12.1 μg kg-1 (levamisole), 53.9 μg kg-1 (cambendazole), 64.2 μg kg-1 (mebendazole), 52.5 μg kg-1 (parabendazole), 105.8 μg kg-1 (thiabendazole), 234.2 μg kg-1 (triclobendazole). The suitability of the assay has been assessed through InterVal Software by quo data GmbH (Germany). The method achieves high quality of the results, good recovery, repeatabilities, within-lab reproducibilities, and wide analytical scope and has practical benefits, low cost, high sample throughput, little labor used and few lab ware.

The ability of bacteria to produce a biofilm is considered an important virulent property in pathogenesis of mastitis. The purpose of studies is to investigate the ability to form biofilms, their density, to determine and compare the sensitivity to antibacterial drugs of planktonic and biofilm forms of the main bovine mastitis pathogens on dairy farms of the Western region of Ukraine.Diagnosis of bovine mastitis, selection of milk samples and secretions of the mammary gland, microbiological studies were carried out in accordance with generally accepted methods. The performed studies have established that among pathogens, both acute and chronic forms of mastitis, the most productive film-forming ability had S. aureus strains, which on average 1.5 times more often formed the biofilm than Str. agalactiae and Str. dysgalactiae strains. It was revealed that S. aureus strains, isolated from cows under the subclinical form of mastitis and at carriage, 2.0 times (p <0.05) more often formed biofilms than in the clinical form of mastitis. The highest sensitivity of planktonic bacteria to pathogens of mastitis of streptococci and staphylococci was to ceftriaxone and doxycycline (100-80.9%). The least susceptible streptococci and staphylococci were to benzylpenicillin 32.3-45.4%, and the susceptibility of S. aureus strains was 19.0%.When determining the influence of antibiotics on biofilm forms of bacteria found that cells in the biofilm are more resistant to antibacterial drugs. It was found that antibiotic enrofloxacin completely inactivated streptococci and staphylococci in biofilms. Also, antibiotics ceftriaxone and doxycycline were also effective on bacteria in biofilms. At the same time, under the action of antibiotics penicillins, aminoglycosides and macrolides, the amount of microbial cells that survived in a biofilm was about lg 5.3 CFU/cm2 of area. Consequently, studies have shown that it is necessary to seek effective methods and develop new drugs that would influence the bacteria in biofilms to effectively treat bovine mastitis.

The study was conducted to evaluate the applicability of ultra high-performance liquid chromatography - tandem mass spectrometry method (UHPLC-MS/MS), establish the MS/MS detection parameters and determine the validation characteristics for the analysis of residual content of avermectins in milk. The UHPLC-MS/MS method has proved to be accurate, practical and universal. This was confirmed by Decision limit (CCα) data: abamectin - 12.56 μg/kg, doramectin - 17.74 μg/kg, eprinomectin - 24.02 μg/kg, ivermectin - 12.53 μg/kg, moxidectin - 44.69 μg/kg, recovery is 88.7-110%. The data obtained for assessing the suitability, accuracy and reproducibility of the results meet the requirements of the European Directive (2002/657/EC). The efficient ultra high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method that was developed and adopted for routine use by the laboratories of veterinary medicine, allows to detect residual quantities of 5 avermectins used in animal breeding for the prevention of helminthiases in food products including milk.

The article presents the results of a toxic biological evaluation of meat (in the muscles of the thigh, pectoral muscles, and the muscles of the lower leg) of broiler chickens using an express method using the infusoria Tetrahimena pyriformis using the Baitril 10% preparation. For the bird of experimental group, this preparation was used by oral administration at the rate of 0.1 ml / kg of body weight for 5 days. The broiler chickens of control and experimental groups were slaughtered on day 6, day 12 and day 14 after the last administration of the drug. For the toxicological evaluation, the muscles with the highest residual enrofloxacin content were used. The criterion for toxicity in biotesting on infusoria is a probable decrease in the number of cells in the culture in 24 hours. It has was been established that when using the veterinary drug the meat of broiler chickens, was not toxic to infusoria Tetrachimena pyriformis already on days 6 after the last feeding . The indicator of the relative biological value of pectoral muscles, muscles of the thigh and lower leg is close by value and tends to increase the relative biological value of the muscles of the research group already on the 14th day after the last application of the veterinary drug. Keywords: toxicity, biological evaluation, enrofloxacin, fluoroquinolones, tetrachimena pyriformis.