The dynamics of changes of nonspecific cellular-humoral immunity parameters of sheep in the conditions of in the conditions of oppression of parasympathetic part of autonomic nervous system was studied in the conditions of the Republic of Belarus. For the experimental animals there was applied atropine sulfate. Experiment was realized by an example of two groups (control and experimental) of yeld ewes. Blood was taken from jugular vein before administration of the preparation, and then in 1, 3, 6, 12, 24 hours, 1, 2, 3 days after the beginning of experiment. As a result of realized study there was stated a directly-proportional dependence in changes of phagocytes activity of leukocytes.

Serological properties of leptospirae bacteria grown on differential nutritive media were studied by the example of sheep in the conditions of the Republic of Belarus. In the experiment there were used 6 pathogenic industrial leptospirae stock: Leptospira pomona VGNKI-6; Leptospira tarassovi VGNKI-4; Leptospira grippothyphosa VGNKI-1; Leptospira icterrohaemorragia VGNKI-2; Leptospira conicola VGNKI-3; Leptospira hardjo VGNKI-5. The results showed a serological difference of leptospirae grown on conventional and experimental media derived from ram's blood.

An interpretation of concepts 'norm' and 'pathology' in the veterinary medicine and medicine from the point of dialectic and materialistic theory was analyzed. There was given an interpretation of 'norm' as a complex of average indexes of state of vital function of body; interpretation of pathological process, pathological conditions and diseases. There was analyzed the philosophical concept of reasons and consequences in etiology and pathophysiologic mechanisms of diseases, as well as criticism of terms causalism and conditionalism

The realized studies of an experimental series of inactivated vaccine showed that the developed biological preparation made it possible to achieve high preventive efficiency in the conditions of cows heavy with calves for the creation in newborn calves the expressing immunity after milk feeding in the first hours of their life. As a result realized in the conditions of the Republic of Belarus production experiment of emulsified vaccine against rotavirus infection and colibacillosis of cattle in animal breeding farms of different regions of the Republic the prophylactic efficacy of a developed vaccine made up 97,9-98,9%. Research results showed that the developed inactivated vaccine caused at the immunizated animals the formation of specific antibodies at a higher level in comparison with other analyzed national and foreign analogue preparations.

Analysis of the epizootological situation in infectious diseases in the world and the Republic of Belarus was presented. The prevention and eradication control strategy of mentioned diseases in Belarus was defined. In Belarus there was stated no cases of special danger infectious diseases of cattle: bovine spongiform encephalopathy; highly pathogenic poultry flu; aphthous fever; since 1982 - Bang's disease; since 1980 - Newcastle disease; since 1999 – anthrax. Preventive maintenance of 30 infectious diseases was based on application of specific prophylaxis.

A description of a method of chemical inactivation of Aujeszky's disease virus by teotropin was studied in the conditions of the Republic of Belarus. The developed inactivated viral suspension was tested for its antigenic activity. On the basis of realized experiments there were determined the optimal parameters of inactivation of Aujeszky's disease virus y means of 0,1% solution of teotropin under temperature of 37 deg C, pH 7,8 and duration of exposition of 24 hours. There were studied indexes of antigenic activity of inactivated virus

Data оn evaluations of therapeutic efficacy of albendazol and fenbendazol agaonst acute and chronic forms of larval cestodiasis of animals were studied in the conditions of the Republic of Belarus by an example of experimentally infested sheep and rabbits. Application of albendazol and fenbendazol both separately and in complex with antioxidant vitamin and mineral additive against the chronic forms of cysticercosis tenuicollis and cysticercosis pisiform was inefficient. But application of albendazol against acute form of cysticercoses caused the lowering of invasion intensity in shepp and rabbits in 3 times, fenbendazol – in 2,6 times. Application of anthelmintic agents in complex with vitamin and mineral composition promoted the lowering of invasion intensity (in 5 and 4,1 times, respectively) and prevented the disease development in 60% of animals.

Analysis of synchronization of oestrus of cows by means of Ovsynch and Pre-Synch methods was realized in the conditions of the Republic of Belarus. Research results showed that estrus synchronization by means of Pre-Synch method proved to be more efficient by means of higher percentage of fertilization after the first and second insemination in comparison with Ovsynch method. Treatment of cows with the substances Surfagon and Tetravit for synchronization of oestrus did not render negative effect on milk quality and safety.

Determination of adaptation and compensation abilities of larval forms of cestodes (cysticercus and echinococci) was realized by means of evaluation of biochemical composition of their internal environment. There was realized the following estimation of biochemical composition of internal environment: Cysticercus tenuycollis from sheep - 34, Cysticercus tenuycollis from swine - 17, Echinococcus granulosus L. from swine - 23. Estimation of biochemical composition of custodies larvaceous forms was realized on the basis of the standard veterinary methods. Research results revealed that osmotic volumetric concentration of internal environment of custodies larval forms was lower than of osmolarity of blood serum. The average value of osmolarity of blood serum for both sheep and swine was 296,63 mmol/l. Research results showed presence of large quantity of specific lipo- and glycoproteins in custodies larva forms. Cysticercotic liquid administrated into suspended matter of microorganism Micrococcus lysadeicticus and leads to lyzing up to 5% of microbal bodies. It was possible to testify the presence of lyzing activity in liquid of larval forms of cestodes. The research results showed that the analyzed larval forms of cestodes had a lot of different and strong defense mechanisms. Adaptation and compensation abilities of larval forms of cestodes had nonspecific character and contained the following: physical mechanisms; humoral immunocompetent factors; and biochemical adaptation

A technology of application autolysis of fodder yeasts (AFY) for the production of products with higher protein content, digestible aminoacids and other nutritive and biologically active substances in comparison with the standard fodder yeasts (provit) was tested in the conditions of the Republic of Belarus by an example of three groups of swine. Animals of the first (control) group were fed with combined feed SK-26 with addition of 2% of provit. Animals of the second group were fed with combined feed SR-26with addition of 2% of AFY, the third group - with addition 4% of AFY. Provit and AFY were included into combined feed instead of excluded protein components in equivalent number. Research results showed that autolysis of fodder yeasts did not render negative influence on productivity of fattening stores. Average daily weight gain of stores was 637-674 g. Calculation of economic efficiency of combined feeding application of 2 and 4% of AFY showed that application of 2% AFY was more economically profitable