Realized in the conditions of the Republic of Belarus experimental infestation of American mink with monoinvasion of Strongyloides martis and parasitocoenoses of Strongyloides martis and Eimeria vison caused significant changes of hematological blood indices. Associations of the nematodes and coccids caused more intensive changes of blood morphological composition in comparison with monoinfection. The level of hemoglobin and erythrocytes at monoinvasion decreased on 18,8 % (р less than 0.05) and 23,3 % (р less than 0.05); in the conditions of an associative form - on 19,1 % (р less than 0.05)) and 31,4%, respectively; at the same time the quantity of leukocytes increased at monoinvasion on 41,3 % (р less than 0.05)), at the associative form - on 54,2 % (р less than 0.05)). In leucogram there were stated an eosonophilia and netrofilia.

Evaluation of influence of monoinvasions and mixed parasitoses on quality and quantity composition of microbiocenosis of gastro-intestinal tract of carnivore was realized in the conditions of the Republic of Belarus. Changes in intestinal microflora of gastro-intestinal tract of dogs with monoinvasions and associated parasitic diseases in comparison with indexes of healthy animals were typical for disbacteriosis and took place towards the reduction of quantity of normal intestinal microflora (bifidobacteria and lactobacteria) and increasing of transient microorganisms: aerobic bacilli, micromicetes, proteus spp, staphylococci, streptococci.

Development of highly efficient antigens for an early immunodiagnosis of cattle fascioliasis (Fasciola hepatica) and studying of its main properties was realized in the conditions of the Republic of Belarus. Received in result of the experiment antigens possessed high specificity and were suitable for use in fascioliasis immunodiagnostics. Research results showed that use of indirect fluorescent (IFA) test and immunodiffusion test for fasciolasis immunodiagnostics of cattle excludes false positive results caused by tuberculosis and hypodermotosis (p less than 0,001).

Results of treatment and preventive maintenance of mastitis of lactating nonmilking cows and heifers with the help of a new probiotic preparation Lactosan realized in the conditions of the Republic of Belarus were presented. The developed new environmentally safe antimastitis preparation Lactosan contained lactic acid bacteria Lactobacillus plantarum and Lactobacillus acidophilus in amount not less than10E7 CFU/cm3 did not render irritating action on mucous membranes, did not cause a sensitization and according to its toxicity indexes could be concern to low-hazardous substances. Therapeutic effectiveness of Lactosan against subclinical mastitis was 84,2-94,1%; in case of serous and catarrhal mastitis – 63,2-68,4%; and after two therapy regimen – 79,0-84,2%.

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

Determination of influence of long acting antihelminthics (Aversictini boluses and boluses with albendazole) and influence of usual antihelminthics (farmatsin, alverm, fenbendavet) on first stomachanimal digestion, as well as on quantity and quality composition of microflora and microfauna in first stomach and large bowel was realized in the conditions of the Republic of Belarus. In course of the experiment there were used 6 groups of calves infested with helminths (Neoascaris vitulorum, Strongylata sp.). Research result showed that different antihelminth preparations to a greater or lesser degree rendered negative influenced on quantity and quality composition of microorganisms in first stomach and large bowel of cattle. Alverm and boluses with albendazole rendered the least influence on microflora and microfauna that could be explained by low toxicity of active substance (albendazole) of the above preparations. Aversictini boluses, fenbendavet, and farmastin changed the composition of microorganisms. It could be explained by high toxicity of preparations containing aversictini which rendered influence not only of gastro-intestinal tract but also on the whole organism. Active ingredient of mentioned above preparations (Aversektin C), being the product of microbial synthesis, rendered the antagonist action on the normal microflora of digestive tract. Negative influence of fenbendavet was caused by the chemical composition of the preparation and neurotoxic action of fenbendazol

Development of new compositions of premixes for cows with milk yield of 4-5 thousands kg per lactation depending on lactation stage and pregnancy was realized in the conditions of the Republic of Belarus. Efficiency of application of premixes in comparison with the standard ones was estimated. Experiment was realized by an example of 3 groups of cows of white-and-black breed; experimental period included beginning milking period (90 days) and the main lactation period (142 days). Cows of the first control group were given premix P60-6M with combined feed. Animals of the second group were fed with premixes created on the basis of carotene and microelements content. Cows of the third group were given premixes in accordance with recommended standards. The refined standards of cow vitamin and trace elements consumption were presented. Formulas of premixes for high-producing cows were presented. The research results showed that the developed formulas corresponded to the physiological needs and their application influenced on metabolism and milk producing ability. Application of experimental premixes made it possible to increase the digestibility of nutritive substancesoin 2,3-7,5%. Application of vitamins and trace elements in heightened doses (on 10-30%) caused the increasing of their uptake and increasing of cuprum, zinc, manganese and cobalt content in blood on 11,6-40,8%

Creation of a composition for disinfection of livestock houses which possessed an expressed sanitizing action and was safe for livestock animals after the repeated application was realized in the conditions of the Republic of Belarus. Formula of the presented the following components: potassium persulphate, amber and citric acids, sodium dodecyl sulfate. For strengthening of disinfecting effect there was also used detergent – sodium dodecyl sulfate (lauryl). Rational balance of components was selected and bactericidal properties of the preparation were estimated at the first stage of the study. At the second stage there was estimated theinfluence of the composition on livestock animals after the repeated aerosol spraying at their presence, as well as the biochemical, morphological and immunological blood indexes of experimental animals. Toxicity of the composition was realized by an example on white mice and rabbits. Research results showed that the composition for disinfection created on the basis of potassium persulphate and organic acids in the presented concentrations rendered the expressed bactericidal action, did not influence on metabolic indexes, had not skin and skin-resorptive action and could be used for air disinfection and surface areas of livestock houses in animal presence

Elaboration of production technology of rape (Brassica napus) phospholipids as one of components of feed additive was realized in the conditions of the Republic of Belarus. The following equipment was used for rapeseed processing: conveyer screw for seeds, conveyer for pressed seeds (seed cake), press Farraet Zralok LC preliminary, press - Farmet Zralok PL finishing, storage-capacity for oil, storage with mixing mechanism, automatic leaf filter, compressor, air vent, air filter. Rape oil was the main product of rape processing and oil seed press cake and rape phospholipides were the additional products. Quality indexes of rape phospholipids (appearance; quantity of obtained phospholipids; moisture content; dry matter content; oil and extractive matter content; total amount of carbohydrates) were analyzed. Results of phospholipids production depending on period of filtration and pressure load in the process of oil filtration were presented. Results of rape phospholipids production depending on air pressure were given. There were obtained the following optimal parameters for phospholipids production: optimal filtration time of freshly squeezed rape oil – 5-6 hours; optimal pressure load of during the filtration of raw rape oil - 2,5-3,0 atmospheres; and optimal air pressure during the filter drying - 2,5-3,0 atmospheres. The proposed production technology of rape phospholipids made it possible to produce 4,5-5,5% of phospholipids from 1 kg of rape

Studying of the comparative productivity of various species and varieties of perennial grasses for the selection of the most productive species and increasing of production capacity of well-balanced feeds with low prime cost was realized in the conditions of sod-podzolic loamy soils of Vitebsk region of the Republic of Belarus. In course of study there were analyzed the following grasses: meadow clover (Trifolium pratense); creeping trefoil (Trifolium repens); great trefoil (Medicago sativa); timothy grass (Phleum pratense); meadow fescue grass (Festuca pratensis); chewing fescue (Festuca rubra); cock's-foot (Dactylis glomerata); common ryegrass (Lolium perenne); meadow foxtail (Alopecurus pratensis); awnless brome (Bromus inermis Leyss), and hybrid of fescue grass and perennial ryegrass. Studying of soil and climatic conditions in the analyzed area showed that leguminous grasses had higher yielding capacity than the cereal ones. After the 4-year observation the studied leguminous grasses provided higher yielding indexes in comparison with the cereal ones per 1 gram: dry matter – on 14,9%; available energy - on 29,7%; crude protein – on 44,7%. For the production of green mass in the conditions of Vitebsk region into the basis of planning of green and raw materials conveyor system there should be taken into consideration terms of beginning of hay cutting ripening of perennial leguminous and bluegrass grasses. Cereal grasses showed higher indexes of sugar content in 1,8 times in comparison with leguminous ones. For the provision of standard content of sugars and digestible protein in energy fodder unit it was reasonable to form grass mixtures on the basis leguminous and bluegrass grasses in ratio 60% and 40% respectively