Searching for new, effective and safe methods of treatment of hookworm disease (ancylostomatidosis) of dogs caused by Ancylostoma caninum and Uncinaria stenocephala was realized in the conditions of the Republic of Belarus on the basis of studying of spices composition and dissemination of Ankilostomatidae, age-specific and seasonal disease dynamics, testing of medical and preventive preparations Univerm and Fenbendazol. In the Republic of Belarus Ancylostoma caninum was stated 4,2% of studied cases and Uncinaria stenocephala – in 14,3%. The maximum intensity of the invasion was stated in summer and autumn periods: in cases of individual keeping – 19,4%; in cases of group keeping the disease transformed into enzootic form with 66,7% affect. In winter period there was the lowest invasion – up to 1,4%. The preparation Univerm administrated twofold with feed in dose of 0,1 mg/kg with 24 hours interval proved to be highly effective therapeutic agent with extensefficiency100%. Anthelmintic Fenbendazol administrated once with feed in dose of 0,005 g/kg proved to be highly effective with extensefficiency 80% and intensefficiency 98,84%. Hematological indexes of sick dogs showed the evidence of erythropenia (4,30-4,80 x 10E12/l), hemoglobinemia (113-119 g/l) and eosinophilia (up to 11%), as well as the increased quantity of leukocytes on 5,46% - 23,61 %, and the lowered quantity of lymphocytes on 15,84 % in comparison with healthy animals indexes

In the conditions of the Republic of Belarus there was developed a method of surgical treatment of servicing bulls with penial tumors including tumor removal by means of gas docker Tail Docker and intravenous 0,5% novocaini solution injection during postoperative stage makes it possible to reduce the duration of surgical operation in 3-4 times, completely remove probability of bleeding, reduce the healing period on the average on 6 days and lower the probability of relapse of tumor.

In the conditions of the Republic of Belarus there was realized a study of age-specific features of level of erythrocytes, haemoglobin in blood, activity of aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, alkaline phosphatase, as well as concentration of calcium, phosphorous, magnesium and ferrum in blood serum of suckling colts in the first 6 months of life. In the studied animals there was stated increased levels, haemoglobin and ferrum concentration in blood, but during the 6th month of life the same indexes decreased considerably. The most considerable changes оf blood serum enzymatic activities occurred at the age of 2 and 6 months. Thus, during the 2nd month of life a raise in ALAT, LDH activity, calcium and phosphorus concentration was noticed. At the age of 6 months ALAT and ASAT levels increased, and LDH activity, magnesium and phosphorus concentration decreased. During the first 6 months of life the ALP activity was on a high level and underwent no reliable changes. As the research showed, blood serum enzymatic activity and concentration of calcium, phosphorus, magnesium and ferrum depended on colt age and change at the process of growth and development of animals.

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

There were presented data on etiology, specific prophylaxis and treatment of the most widespread infectious diseases of fishes in the Republic of Belarus: aeromonosis, pseudomonosis, swim bladder inflammation (air bladder disease), viral branchionecrosis. For the preparation of highly efficient specific medical and veterinary preparations it was recommended during the outbreaks of fish diseases to allocate the local pathogens on the basis of which it was recommended to produce vaccines both for perinatal and immersion administration for their wide use both for commodity fishes and for different ages and categories

The information on necessity of carrying out of monitoring and purposeful scientific research on studying of infectious diseases of wild animals in hunting farms of the Republic of Belarus was presented in order to lower their negative influence on state of a population of resource species of wild animals. On the territory of Belarus in the studied wild animals there were stated 42 infectious diseases, including 36 ones which were the reasons of death of valuable hunting and fur-bearing animals. The greatest threat from infectious diseases was represented by rinderpest, pasteurilosis, salmonellosis, furiousness, necrobacillosis, listeriosis, botulism, tuberculosis, pseudorabies, the Siberian ulcer and hoof-and-mouth disease. Many diseases represent danger to human beings, the other lead to a various degree losses for the hunting economy of the country

There was presented a territorial analysis of epizootic situation on rabies in the administrative districts and regions of the Republic of Belarus in the period from 1986 up to 2008. The situation of strain was stated on the territory of Vitebsk (28, 4%) and Minsk (20,2%) regions. The most stable epizootic situation was stated in Shumilin, Braslavsk and Vitebsk districts of Vitebsk region, as well as in Vologin and Minsk districts of Minsk region. Only in 1990 and 1997 there were stated no cases of rabies in Brest and in 1996 in Mogilev regions. In other years no regions were free from this infection. Economic damage from rabies cases in agricultural animals in period 1986-2008 was over 2 milliard of Belarusian rubles.

Study of subclinical chlamydial endometritis of black and motley cows of 2-5 lactations with 5000-6000 kg milk per year was realized in the conditions of the Republic of Belarus. Research results showed that reaction of pH medium of uterus content of healthy ill cows with subclinical chlamydial endometritis did not change and was within the limits of 8. Diagnostics of subclinical chlamydial endometritis during estrum was realized according to presence of estrous mucus in purulent inclusions, as well as of neutrophil in tissue smear and by colouring by Stamp of tissue smears from a uterine lining and in serological reactions. In inter-estrous cycle it was possible to establish a latent chlamydial endometritis according to slightly opened uterus channel, state of uterus walls and presence of yellow bodies in an ovary, increasing of titers in antibodies in two and more times in dual tests of serum.

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.