In the conditions of the Republic of Belarus there was studied the interrelation between content of major nutrient elements (calcium and phosphorous) and trace elements (iron, copper, cobalt, and manganese) in forages and blood of first-calf cows at the first and last stages of lactation. Also, there were developed formulas of mixed forages and a premix for these animals. The studies were realized at the Agricultural Production Co-operative Olgovskoe of Vitebsk region (Belarus). Research of analysis of forages and state of mineral metabolismat heifers made it possible to draw following conclusions: in cow rations there was marked the deficiency of vitamin D, as well as some trace elements (cobalt and manganese) in the conditions of calcium and phosphorus excess. In spite of a high content in a calcium in diets, it was noted than in blood plasma the concentration of this element was below the standard for the majority of animals. Lack of cobalt and manganese of whole blood of cows was connected with a low level of these elements in cow diets. The surplus contents of copper in forages and blood of animals against the background low activity of ceruloplasmin the weakened antioxidant defense of heifer cows. For preventive treatment of possible hypo trace element deficiencies and metabolic disorders of heifer cows at the final stage of lactation there can be recommended the correcting of cow diets with inclusion into their composition of the developed for compound of mixed fodder and premix.

In the conditions of the Republic of Belarus there was analyzed the influence of inclusion into broiler chickens diets of probiotoc preparation Bifidoflorin zhidkij (liquid) and prediotic veterinary drug Biofon AIL on the natural resistance, hematopoiesis, growth, metabolic function, development and viability of broiler chickens. In course of the study there was analyzed the dynamics of total haemoglobin, total protein of blood serum, albumins and globulins of broiler chickens which were fed with veterinary drugs probiotoc Bifidoflorin zhidkij and prediotic Biofon AIL. Indexes of chicken viability and life weight gain were marked. Research results showed that application of the presented veterinary preparations rendered the growth promoting action, lowering of disease incidence, increasing of chicken viability, increasing of live weight gain and stimulation of metabolic processes in the most intense period of poultry growing. All these factors were expressed in highest degree after the combined application of the probiotic and prebiotic veterinary drugs.

In the conditions of the Republic of Belarus there was studied the possibility of increasing of meat yield productivity of ducklings of Temp cross in the conditions application of parental lines of Peking ducks of German breeding Stolle Seddin Vital (SVV) cross. In course of the study there was realized a comparative evaluation of linear and crossbred ducklings in accordance with meat qualities and blood indexes. There were presented the results of morphological composition of liner and crossbred duck carcasses; dynamics of changes of lipid exchange (total lipids; cholesterine; triglyceride) of ducklings; morphological composition of carcasses of father and mother combinations; blood indexes of ducklings; blood indexes of crossbred ducklings of final combinations. Research results showed that crossbred ducklings had high meat properties which exceeded the purebred ones. In ducklings with lower indexes of fattiness of carcasses there was noted the lowering of concentration of total lipids, cholesterine and triglyceride in blood.

In the conditions of the Republic of Belarus there was studied the pathology and biology of cattle capillariasis. Capillariosis invasion rendered a substantial invasion on blood morphological composition which was revealed in lowering of erythrocytes and hematoglobulin, as well as in increasing of leukocytes quantity. There was noted the lowering of the natural resistance and immune reactivity. There were stated substantial deviations in protein metabolism which was expressed in lowering of total protein, quantity of albumins, changing of albumin and globulin coefficient, increasing of globulins. In the conditions of blood biochemical analysis of infesrated animals there was stated a disorder of vitamin and mineral metabolism; increasing of alanine aminotransferase and aspartate aminotransferase enzymes activity. Development of Capillaria bovis was realized in a direct line. In the natural habitat development of Capillaria bovis eggs varied from two up to three months.

In the conditions of the Republic of Belarus there was studied the nonspecific resistance of lambs of Latvian Black Face breed during the colostrum and milk fed period of their growth development. In course of the experiment there were used 10 newborn lambs. Analysis of resistance was realized in accordance with a scheme: before colostral milk sucking; in 6, 12, 24 hours; in 3, 7, 14, 21 days; in 1, 2 and 3 months after birth. In lambs during the colostrum and milk fed period of growth there were marked two critical periods, which were characterized by low indicators of resistance: before colostral milk uptake and at 7-21 day-old age. Increasing of leukocytes, bactericidal, lysozymic activity of blood serum, phagocytal activity of leukocytes, crude protein and antibodies in the first days of lamb life took place due to their entrance in blood with colostral milk, just because at this time the intestines wall possessed ability to transit in native condition the antibodies, enzymes, and leukocytes. At 7-21 day-old age in connection with reduction of these factors quantity of in colostral milk, and also due to reduction of intestines capacity, their was stated that their entrance in blood of newborn lambs decreased, but at 3 month old age of lambs there were stated to form internal protective factors of resistance because of which their quantity in blood started to increase.

In the conditions of the Republic of Belarus there was studied a state of lipid peroxidation, antioxidant protection and activity of hepatospecific enzymes of blood plasma of piglets. Research results showed that weanling piglets which had low body weight in the conditions of industrial breeding technology were characterized by high intensity of processes of lipid peroxidation. At the same time, the antioxidant system reacted adequately to the mentioned above changes. There was noted a high dependence between the content of Schiff's bases which were the end-products of lipid peroxidation processes, and the activity display of amplifier hepatospecific enzymes of blood plasma of weanling piglets. The received results of research can be used for estimation of a condition of prooxidant and antioxidant status, and in a complex with data on activity of sorbitol dehydrogenases, isocitratdehydrogenases and glutamatedehydrogenases - for an estimation of a functional state of a liver of weanling piglets with low body weight at an initial stage of their breeding.

In the conditions of the Republic of Belarus there was realized a comparative study of peculiar features of influence of combined application of Khelavit preparation and protein-vitamin-mineral feed supplements Khendriks and Spaeta-kontsentrat on health status of cows and quality of obtained cow milk after application of these preparation for the preventive treatment of osteodystrophy. In course of study there were analyzed haematologic and biochemical blood indexes of cows after application of the experimental preparations. Results of physical and chemical indexes of milk were presented. Research results showed that the analyzed protein, vitamin and mineral feed supplements caused the normalization of biochemical blood indexes in comparison with animal of a control group. Besides, application of mentioned above drugs promoted the increasing of veterinary and sanitary quality and technological properties of produced milk.

In the conditions of the Republic of Belarus there was determined the influence of different rates of lithium addition into mixed fodders for sows feeding on hematological indexes and their reproductive qualities. In course of the study there was analyzed the dynamics of body weight of sows over the reproductive period; indexes of productivity of sows (number of born piglets; weight of 1 piglet; litter weight; weight of weanling piglets; number of weanling piglets; etc.); hematological indexes of sows; state of humoral factors of immunity of sows. Research results showed that in case of lithium application in diets of sows there was stated an improvement of hematological indexes and immunity functions and resistance. The optimal level of lithium in rations was 15 milligram per 1 kilogram of dry matter of a diet. This dose essentially promoted the increasing of reproductive performance, piglets weight and milking capacity of sows as well as better viability of piglets.

In the conditions of the Republic of Belarus there was analyzed the efficiency of application of a probiotic lactic casein feed additive DKM which was developed in the Institute of Microbiology of the National Academy of Sciences of Belarus. The analyzed additive contained specially selected lactic-acid bacteria with a high bioartificial potential of metabolites. In course of the experiment there was studied the consumption of fodders (milk; oats; mixed fodders) by experimental calves; dynamics of live weight gain in the beginning and at the end of the experiment; average daily weight gain. Also, there were analyzed the background indexes of blood serum of calves, as well as the indexes of blood serum of calves in a month after application of DKM additive. Research results showed that application of the feed additive DKM promoted better palatability and use of fodders and rendered positive influence on animal productivity. Also, there was marked the normalization of metabolism that was proved y the laboratory tests of blood serum.

In the conditions of the Republic of Belarus there was realized the determination of efficiency of application of saline and chelate forms of copper and cobalt for treatment of anemic syndrome of cattle. It was found out that lack of copper and cobalt in cattle diets in the conditions of normal supply of iron could be a cause of cattle anemic syndrome. It took place because of the iron adsorption disorder in intestines and its inclusions in haem, as well as lowering of ehritropoztin synthesis. In the conditions of administration of copper and cobalt-containing preparations for animals there was noted the increasing of iron and haemoglobin content in blood. Administration of ethylene diamine tetraacetates of cobalt and copper made it possible to reduce considerably all evidences of clinical and laboratory symptoms of anemia and hypomicroelementosis in comparison with application of copper sulphate and cobalt.