In the physiological experience spent on male pigs-manufacturers, we had been studied influence of various doses of selenium (10 mg, 20 and 30 mg) in structure premix on nutrients. It is established, that increase of level of selenium in mixed fodders for male pigs-manufacturers to 30 mg/kg especially promotes increase in degree of use in their organism of fat to 58,7%; (P less than 0,05), the digested nitrogen to 62,1%, calcium – to 78,3% and phosphorus – to 72,5%

The use of subcutaneous progesterone-releasing devices in superovulatory treatment allow to get high results of embryo production per donor, viability and pregnancy rates after embryo transfer in cattle. Application progesterone hypodermic inserts has allowed to lower the cost price of one received embryo on 28461 rubles

Using macro and microelements, vitamins A and D in correspondence with norms of Institute of Animal Husbandry (1992) per 1 kg of dry substance of a diet: phosphorus - 5,29 g, calcium - 7,46, sodium - 5,59 g, copper - 12,64 mg, zinc - 77,26, magnesium - 77,26, vitamins A and D correspondingly - 23,74 and 1,02 thousand ME for highly productive lactating cows with average daily milk yield of 32 kg at summer feeding compared to Agricultural Academy norms (1985) promotes increase of the so called relative products outcome and profit from basic fatness (3,4%) milk sale per 1 animal at 411 rubles

The use of low intensive red spectrum laser radiation for prevention of abomasoenteritis in calves is effective method. As a result the increase of erythrocytes level and saturation of them with hemoglobin happens. Natural resistance with bactericide and lysozyme activity are going up phagocytosis of neutrophils is activated. The most successful method are magnet-laser radiation of blood and laser acupuncture. There was studied the low intensive red spectrum laser radiation for prevention of abomasoenteritis in calves. During the research it is established, that preventive efficiency at abomasoenteritis in the first trial group has made 80%, in the second and the third - 90%. As a result of the spent work high preventive efficiency of action of the low intensive red spectrum laser radiation is established at prescription of through-skin blood irradiations by the therapeutic laser in a combination to a constant magnetic field and as a result influences on biologically active points. Application of these ways allows to reduce level of disease of animal abomasoenteritis. As a result of physiotherapeutic influence there is content increase of erythrocytes in blood of calves and saturation their haemoglobin. Natural resistance with bactericide and lysozyme activity are going up phagocytosis of neutrophils is activated. The most successful method are magnet-laser radiation of blood and laser acupuncture. It is caused by that positive changes occurring in an organism, have been more brightly expressed and besides preventive and economic efficiency of these ways of irradiation also were at higher level. In the tabular form dynamics of morphological indicators at calves under the influence of laser radiation, dynamics of indicators of natural resistance at calves as a result of the laser therapy, some biochemical indicators of blood is presented at carrying out of research.

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

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.

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%.