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.

Data on changes of infectious titer of Porcine Reproductive & Respiratory Syndrome (PRRS) virus depending on variability of cultivation conditions was analyzed in the conditions of the Republic of Belarus. There were determined the regimes of cultivation which made it possible to minimize the terms of virus containing material production up to 3 days. The following factors influenced the infectious titer of PRRS: adaptation to cell culture; completeness of cell culture monolayer; number cells moving into stage of logarithmic growth; infectious dose of virus; storage duration; usage intensity.

The physical and biological properties of a produced in the conditions of the Republic of Belarus nonspecific blood serum of animals according to an improve technology corresponded to all necessary standards. The prophylactic efficiency of nonspecific blood serum of animals was 80%, that was on 10% higher than serum of convalescents. Therapeutic effectiveness of nonspecific blood serum was 90%, that was on 8% higher than serum of convalescents

Study of parasitocoenoses of digestive system of Ayrshire breeds of cows and heifers was realized in the conditions of the Republic of Belarus. In course of investigation there was presented a highly efficient universal sedimentation and flotation method with centrifuging for diagnostic of low intensity infestations of cattle. Heifers of Ayrshire breed the total infestation with parasites of gastro-intestinal tract was 100%. Species composition of parasites per one animal was 2,0 +/- 0,258. In winter period the components of parasitoses of a digestive tract were the following: eimeria, strongylats, fascioles, moniezia, nematodes, trematodes and cestodes. In cows of Ayrshire breed the total infestation was also 100%, mixed infestation – 70,0 %. Species composition of parasites per one animal was 2,55 +/- 0,170. In winter period the components of parasitoses of a digestive tract were the following: eimeria, strongylats, fascioles, and capillariasis

Data on development of an antigen on the basis of larvae of warble flies grubs (Hypodenna bovis) for diagnostic of spontaneous cattle hypodermosis by means of the indirect fluorescent (IFA) test and with application of blood serum and milk samples realized in the conditions of the Republic of Belarus were presented. Specificity and sensitivity of experimental sample of antigen for revealing of spontaneously infestated with larvae of warble flies with IFA test at hypodermotosis has made about 100%.

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.

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%.

General characteristic of parasitologic situation at the exclusion zone, some aspects of new conditions influence on separate systematic groups of mammal parasites Polesye State Radiation and Nature Reserve of the Republic of Belarus were presented. Research of helminth fauna and helminthological situation was realized by an example of 1 European bison, 7 mooses, 20 roe deers, 26 boars, 25 wolves, 50 racoon dogs, 6 foxes and 3 beavers. Scatoscopy of the animal excrements was realized by Kalantaryan method with saturated solution of sodium saltpeter, Berman method. Research results revealed 66 helminth species belonging to 4 classes and 34 families. There were found 10 parasite species at bison, 16 – at mosses, 17 – at roe deers, 16 – at boars, 8 – at deers, 23 – at wolves, 13 – at raccoon dogs, 13 – at foxes, 9 – at badgers and 1 – at beavers. Analyze of helminthofauna of the analyzed area showed that the nature reserve had its own helminthes complex. A lot of stated helminth species were parasites with a wide range of hosts, including domestic animals, and cattle. Wolves, foxes and raccoon dogs were hosts of some custodies invasions. Carnivorous animals and murine rodents were hosts of trichinosis invasion, which was stated at 41,2 % of raccoon dogs, 33,3 % of foxes and 16,7 % of wolves. Also trichinas were stated at bank vole (1,3%), yellow-necked mouse (2,7%), and house mouse (16,6%)

Investigation of influence of water improved by potassium permanganate solution on welfare and productivity of piglets was realized in the conditions of swine breeding complex in the Republic of Belarus. In the experiment there were used 2 groups of 30-day old piglets. In course of 75 days of experiment the running water of pig complex was used for watering of piglets of control group. Piglets from the experimental group were given water with addition of 0,1% solution of potassium permanganate. Analysis of obtained results showed that water with potassium permanganate promoted the increasing of natural resistance of piglets. At the same time there was stated the increasing of lysozyme and bacterial activityin blood serum. Application of improved water promoted the increasing hemoglobin on 4,8-4,5%, erythrocytes - on 2,9-4,2% in comparison with control. Content of total protein increased on 2,2-2,8% in the experimental groups, lisozyme activity - 6,9-7,0% and bacterial activity - on 5-6,9%. Application of improved water did not influence the glucose and potassium concentration in blood. In the experimental group there was stated the increased lipid concentration on 3,1-6%, cholesterol - on 4,4-6,3%, potassium level - on 2,5-4,5%, phosphorus - on 0,7-5,3%, sodium - on 1,4-3,8%. Application of water with КMnО4 increased average daily weight gain on 5,2-4,2%

Realized in the conditions of the Republic of Belarus studies showed that management of cultural landscapes should be based on the models which make it possible to present a proper evaluation of yielding capacity of different types of agricultural lands taking into consideration land quality and influence of natural and climatic factors. Dynamics of yielding capacity of green mass and application of mineral fertilizers at the natural and improved haylands of Belarusian Poozerye region was analyzed. There was noted a determinate variation of grass yields at pasture lands and plowing lands in various years. The presented mopdels made it possible to calculate the average yielding capacity of grasses cultivated at pasture lands and plowing lands in any year, as well as to forecast the extent of risk of yield capacity taking into account yield variability in different years. It was proposed to plan the production volumes of fodders for animal husbandry branch taking into account the variability of yielding capacity at various years under the influence of various unregulated natural and climatic conditions