In the conditions of the Republic of Belarus there was analyzed the metabolic status of cows in the finishing period of pregnancy, as well as influence of its disorders on clinical status and breeding and economic indexes of new-born calves. Research results showed in pregnant cows in interlactation period there was stated the development of subclinical poly-hyper trace element deficiencies. There was realized the analysis of indexes of trace elements metabolism in cow blood; blood indexes characterizing protein metabolism; as well as biochemical blood indexes characterizing the carbohydrate metabolism and functional state of liver and kidneys. In the conditions of subclinical poly-hyper trace element deficiencies of cows there were revealed the biochemical changes which showed the lowering of the functional activity of liver and intoxication. Economic and clinical indexes of calf crop were analyzed. Research results showed that in calves (obtained from cows with trace element deficiencies) in an early extrauterine life there statedthe development of a toxic form of dyspeptic disorder which was accompanied with high degree of young stock death.

Determination of influence of combined feed with carnitine and 3% lipids on digestibility of nutrients in ration of fattening stores was realized in the conditions of the Republic of Belarus by an example of 8 castrated male pigs of Belarusian meaty breed with body weight of 60-65 kg. Piglets were divided into 2 groups in accordance with analogue pair principle. Selected animals were kept in single cages specially equipped for fecal and urina gathering. Both groups of animals were given the same combined feed SK-26 which included 3% lipids. Experimental piglets were fed with combined feed with carnitine in dose of 50 g/t of mixed fodder. The mixed fodder contained the following ingredients: wheat; triticale; grain mixture; sunflower oil cakes; liprot SG; tricalcium phosphate; calcium carbonate; salt; premix KS-4; vegetable oil. Research results showed that enriching of combined feed carnitine rendered positive influence on digestibility and absorbency of nutrients. It made it possible to increase the digestibility of dry matter on 2,1%, organic matter on 2,0%, crude protein on 3,1%, crude fat on 7,4%, crude fiber on 8,6%, free-nitrogen extract on 1,1%, as well as to increase nitrogen, calcium and phosphorus absorbency. Quantity of saved nitrogen in the experimental group (with carnitine additive) was on 21,1% than in control one. Quantity of saved nitrogen and absorbed with feed was on 9,8% and 5,6% respectively higher than the same indexes for the control group; calcium - on 15,5% and 2,6%, phosphorus - on 23,3% and 3,7%, respectively

In the conditions of the Republic of Belarus clinic and production conditions there was analyzed the prophylactic and therapeutic efficacy of a new national complex iron dextrane preparation Ferovital against deficiency (nutritional) anemia of new-born cattle and swine. In course of the study there were analyzed results of hematological and biochemical tests of blood of piglets which were administrated with Ferovital preparation. There were also marked the general economic index: live weight gain, disease incidence, piglet death rate, etc. Research results showed that the Ferovital preparation had an expressed prophylactic and therapeutic efficacy both in clinic and production conditions.

Possibility of increasing of natural resistance of young livestock animals and productivity of piglets after application of experimental feed additive including dolomite powder was realized in the conditions of the Republic of Belarus. In course of study there were analyzed housing conditions of piglets; the hygienic examination of feeding rations; influence of dolomitic meal on piglet resistance and productivity. Piglets of the first (control) group were fed with standard total ration. Animals of the second and the third experimental groups were given dolomite powder in ratio of 1% and 2% of combined feed mass. Chemical content of dolomite powder, hematological indexes, disease incidence and piglet productivity were analyzed. The research results showed that in feeding rations of piglets in the analyzed swine breeding complex there was stated the deficit of calcium (14%), phosphorous (26%), magnesium (15%), cuprum (9%), zinc (27%) and manganese (27%). Research results showed that application of dolomite meal is efficient for the prophylaxis of mineral deficiency, and made it possible to increase the level natural resistance: serum bactericidal activity - on 16,4% and hemoglobin - on 19%. The optimal dolomite dose of dolomite was 2% and it promoted the lowering of disease incidence, increasing of viability and average daily weight gain