In the development of effective methods of prevention and treatment of poultry today, importance is given to probiotics based on microbial cultures, in particular, lactobacilli, bifidobacteria, yeast, etc. In contrast to antibiotics, the use of probiotics stimulates the immune response of animals, restores the microflora of the gastrointestinal tract, and ensures its optimal ratio. At the same time, livestock products remain safe for the consumer. The purpose of our work was to conduct comparative clinical trials of the efficiency of the probiotic feed additive Probion-forte in terms of productivity, blood indices, and histological structure of immune organs of chicken broilers during fattening. The clinical studies were carried out with broiler chickens of “Cobb-500” cross at the age of 2 days, which were formed into four groups (300 units in each one). In order to determine the efficiency of application, probiotic feed additives were given to chickens in different concentrations during the growing period, together with the main diet. The first group (1st) was given probiotic Probion-forte in the dose of 1 g/kg of feed, the second group (2nd) – Probion-forte in a dose of 0.5 g/kg, the third (3rd) one – a probiotic-analog “Bio plus 2B” in a dose of 0.4 g/kg; the forth (4th) group was a control group – chickens received an essential diet, without adding any feed additives. The compound feed was provided according to norms recommended for the cross “Cobb-500”, considering age. On the 15th, 30th, and 43rd day of the test, 20 units were selected for hematological, pathomorphological and microbiological tests. The productivity of birds of all studied groups was evaluated by the average daily gains, safety, feed conversion, and slaughter output. The stabilized with EDTA chicken blood was used for morphological studies, and blood serum – for biochemical and immunological studies. Comparative clinical studies have shown that adding to the main diet of broiler chickens probiotic feed additive Probion-forte at a dose of 0.5 and 1.0 g/kg throughout the growing period increases the safety and improves feed digestibility, and increases the bird’s European Efficiency Index. Based on the obtained hematological, biochemical, and immunological parameters of blood, it can be argued about the activating effect on the body of broiler chickens probiotic feed additives, namely the intensification of reanimation of free amino acids, which increases the content of the studied metabolites of lipid metabolism, which chickens use as energy and plastic material. Stimulating cellular and humoral protection, nonspecific resistance is established, confirmed by a high level of lysozyme activity in blood serum and significantly higher content of T- and B-lymphocytes, NK-cells, and γ-globulins. The macro- and microscopic structure of the studied immune organs is preserved in all groups of broiler chickens. Compared with the control group, morphometric examination in the immune organs of broiler chickens of the first and second groups revealed an increase in the area and density of lymphoid elements, an increase in the number of plasmablasts and plasma cells, much higher structural and functional capacity of cells, which was reflected at the ultrastructural level. The most significant difference was found in the 1st group of chickens fed with the feed additive Probion-forte at a dose of 1.0 g/kg of feed.

The article presents the results of clinical trials on pigs of the veterinary medicinal product Vetaseptol (powder for oral use), manufactured by “Ukrvetrompostach LLC”. The drug was used orally with feed for the treatment of acute respiratory infection in 2-month-old piglets in the dosage recommended by the manufacturer. Before the experiment, microbiological studies were conducted on selection and identification of microorganisms, pathogens of respiratory infection in pigs, and establishing of their sensitivity to the active substances of the drug (oxytetracycline and erythromycin). During the experiment, constant observation of the clinical condition and physiological parameters of the body of the experimental animals were performed. Evaluation of hematological and biochemical indicators was carried out according to recognized methods. The therapeutic efficiency was compared with the data obtained before the treatment and after using the comparator drug. On the basis of obtained data and their statistical analysis, conclusions about the effeciency of Vetaseptol in the treatment of pigs, suffering from streptococcosis, and its effect on their organism were made. According to the evaluation of the animal’s clinical condition and the results of laboratory tests obtained, it was established that the tolerability of the studied drug for the treatment of respiratory infection of young pigs was good. During the experimental period and two weeks after the use of the drugs, no side effects were detected and no changes in the behavior of the piglets were observed. The therapeutic effectiveness of the test drug was 100%, and the recovery time was almost 5 days. A comparative analysis of piglet’s hematological indicators showed a reliable decrease of monocytes number in the animal’s leukogram after antibiotic therapy. The normalization of the piglet’s leukogram indicated the termination of inflammatory processes and the improvement of the physiological state of animals. The serum biochemical profile of experimental animals hasn’t changed significantly. Laboratory studies did not reveal hemo- and hepatotoxic effects of the antimicrobial drug.

The article presents the results of clinical trials of a veterinary medicinal product based on butaphosphane and cyanocobalamin on weaned piglets during the growing period with signs of anemia. The drug was used in the dosage recommended by the manufacturer - intramuscularly in a dose of 2.0 ml per animal, once a day, for 5 days. Blood for laboratory research was taken from animals before and after the use of the drug. Research of hematological and biochemical parameters was carried out according to generally accepted methods. The therapeutic effectiveness of the drug was evaluated by comparing it with the data obtained before the start of treatment. Based on the obtained data and their statistical analysis, conclusions were made about the effect of the drug on the morpho-functional state of the piglets' body. A comparative analysis of hematological indicators of piglets before and after the use of the drug showed optimization of the leukogram, which was a sign of improvement in the physiological condition of the animals. Activation of hematopoietic processes was noted, confirmed by indicators of red blood of piglets. The biochemical profile of the blood serum of experimental animals after treatment showed a positive effect on indicators of mineral and protein metabolism and the state of the hepatobiliary system. Based on the assessment of the clinical condition of the animals and the obtained results of laboratory studies, it was established that the tolerability of the studied drug when administered to piglets with signs of anemia was good, no changes in the behavior of the piglets were detected. Side effects and negative phenomena have not been established. Monthly monitoring of the clinical condition of piglets confirmed the safety of the drug when used in the dosage and method of administration recommended by the manufacturer. The results of hematological and biochemical studies confirmed the positive effect of the drug on the body and its effectiveness in the treatment of the anemic state of piglets and the correction of the physiological state of piglets.

Doxycycline is a bacteriostatic antibiotic from the group of tetracyclines, a semi-synthetic derivative of chloretracycline. It is a broad-spectrum antibiotic that is active in gram- positive and gram- negative bacteria, including some anaerobes. Therefore, the use of doxycycline drugs is relevant to solve the problem of treatment and control of mono- and polyinfections, which are caused by doxycycline sensitive and other antibiotics resistant to other antibiotics. The article presents the results of clinical studies of a new veterinary drug Doxal (water-soluble powder for oral administration), production of PJSC “Technologist” (Ukraine), an active pharmaceutical ingredient of which is doxycycline, in the treatment of acute intestinal disease in broiler chickens. A high level of therapeutic efficacy and safety of the Doxal studied drug in the treatment of chickens 25 daily age with colibacteriose-claspidiosis infection was established. The diagnosis was made on the basis of anamnestic data, a clinical picture of the disease, the results of pathoanatomical section and bacteriological examination. Microorganisms – pathogens of infection, their level of sensitivity to doxycycline were selected and identified. Therapeutic efficiency of the tested drug was not inferior to the drug-comparison of Doxatib®, production of KRKA DD Novo-Mesto (Slovenia), similar in dosage form and the content of the active substance. According to the results of laboratory tests, a positive effect of Doxal on the morpho-functional state of the body of chickens in the treatment of acute colibacteriosis-claspidiosis infection was revealed, which is confirmed by normalization with a high percentage of the reliability of morphological and biochemical blood indicators to the values of clinically healthy bird. Comparative clinical studies have confirmed that Doxal drug is effective chemotherapeutic agent for the treatment of bacterial infections in chickens caused by microorganisms sensitive to doxycycline, and is analogous to Doxatib® by it’s action.

In order to improve the digestibility and absorption of feed, metabolic processes, growth and development of animals, increase the resistance of the body immunomodulatory agents, probiotics, prebiotics, combined enzyme-probiotic feed additives are widely used. The purpose of our work was to conduct comparative clinical trials of the effectiveness of the probiotic feed additive Probion-forte in terms of productivity, blood indices and histological structure of individual internal  pigs organs during fattening. The researches were carried out on 120 piglets of big white breed at the age of 28 days, which were divided into 4 groups with 30 units in each one. The probiotics were added to feed in different concentrations in order to determine their efficiency and examine influence on piglets organism: the first group was given probiotic Probion-forte in dose of 1.0 g/kg (10 weeks); the second one – Probion in dose of 1.0 g/kg (6 weeks) and 0.5 g/kg (4 weeks); the third one was given probiotic Bio Plus 2B in dose of 0.4 g/kg for 10 weeks; and the fourth one was a control group. The compound feed was provided according to norms recommended for big white breed taking into account age. On the 42nd day (6 weeks) and on the 70th day of test 10 units were selected for haematological, pathomorphological and microbiological tests. The productivity of animals of all studied groups was evaluated by the average daily gains, safety, feed conversion and slaughter output. The stabilized with EDTA piglets’ blood was used for morphological studies, and blood serum – for biochemical studies. The clinical trials have shown that the application of Probion-forte, as a feed additive for fattening of piglets within 10 weeks after weaning, did not cause adverse reactions, was well tolerated by animals and contributed to the improvement of the processes of erythropoiesis and leucopoiesis, increased of serum total protein content. The increasing activity of serum transaminases indicated more intense metabolic processes in experimental animals’ organism, which was confirmed by increase in average daily weight gains and slaughter output compared to control. In the microscopic examination of the thymus, spleen, lymph nodes, intestines, liver, the characteristic histological structure of the organs was preserved and indicated their active morphofunctional state throughout the study period. Morphometrically the increase in the height of the villi in the duodenum and the size of the thymus lobes in piglets, which were fed with probiotic feed additives was established. The efficiency and appropriateness of the application of these products was confirmed in the first and second experimental groups. However, the most significant difference was observed in piglets fed with Probion-forte for 10 weeks at a dose of 1.0 g/kg of feed.