Creation of a composition for disinfection of livestock houses which possessed an expressed sanitizing action and was safe for livestock animals after the repeated application was realized in the conditions of the Republic of Belarus. Formula of the presented the following components: potassium persulphate, amber and citric acids, sodium dodecyl sulfate. For strengthening of disinfecting effect there was also used detergent – sodium dodecyl sulfate (lauryl). Rational balance of components was selected and bactericidal properties of the preparation were estimated at the first stage of the study. At the second stage there was estimated theinfluence of the composition on livestock animals after the repeated aerosol spraying at their presence, as well as the biochemical, morphological and immunological blood indexes of experimental animals. Toxicity of the composition was realized by an example on white mice and rabbits. Research results showed that the composition for disinfection created on the basis of potassium persulphate and organic acids in the presented concentrations rendered the expressed bactericidal action, did not influence on metabolic indexes, had not skin and skin-resorptive action and could be used for air disinfection and surface areas of livestock houses in animal presence

Determination of the positive aspects of application of a feed additive on the basis of sodium humate and malt sprouts fortified with oaky extract in diets of high-productive cows in dry period was realized in the conditions of the Republic of Belarus. Cows of black-and-white breed with average body weight 600 kg and milk-yield 6000-7000 kg were used in the experiment. Cows of experimental groups in addition to their main diet were fed with the resolved additive in doses 10-20 ml/100kg of live weight. Formula of humic additive with draft name Ehkolin-3 was developed on the basis of Ehkolin additive. Ehkolin additive in its composition contained the following compounds: organic substances; mineral substances; humic substances; melanoids; reducing agents; phenolic compounds; organic acids, and total nitrogen. Research results showed that application of the analyzed additive promoted the increasing enzyme activity in blood serum. Body weight of new born calves in experimental groups was higher than in control group. Symptoms of diseases of the digestive tract disappeared in 4-5 days in the experimental calves. Cows of the experimental groups had good colostral milk with density 1056 kg/mE3 and 55% of immunoglobulins. Impregnation capacity of in one experimental group was 50% after the first insemination, and only 33,3% and 20% in the control and the second experimental group, respectively

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

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

In course of a long-term selection breeding activities in the conditions of the Republic of Belarus on the basis of Belarusian Large White breed of swine there were created two high-productive lines - Delfina 37755 and Svitanka 3884. Individual selection of animals was realized in accordance with the main indexes of productive ability, development and conformation type. There were selected parent lines, there were used methods of intrastrain breeding and hybrid between lines, mild inbreeding on parental line. Bores and breeding sows were evaluated in accordance with their posterity productivity by means of a control feeding method. Productive indexes for Delfina 37755 line were 11,7 piglets, for Svitanka 3884 line – 11,9 piglets; age of live weight gain of 100 kg – 189 and 182 days, respectively; average daily weight gain – 735 gram and 749 gram; forage expenses – 3,5 and 3,51 fodder units; backfat thickness – 27,2 and 26,2 mm; ham weight – 10,9 and 11,2 k, respectively

Determination of influence of polymorphic variants of genes of kappa casein, beta-lactoglodulin and alpha-lactoalbumin on indexes of milk producing ability (milk yield, fat and protein content) of brood cows of Belarusian white-and-black breed was studied in the conditions of the Republic of Belarus. In course of analysis of polymorphism of kappa casein gene there was revealed the exceeding of frequency index of allel CSN3**a over the index of allel CSN3**b (0,795 and 0,205 respectively). Studying of polymorphism of beta-lactoglodulin gene showed that the frequency indexes of allel variants formed in the following way: BLG**a - 0,489 and BLG**b - 0,511. There were revealed three genotype variants of alpha-lactoalbumin among which the highest frequency indexes were stated for heterozygous genotype LALBA**aa *(32%) and LALBA**bb (14%). There was calculated the genetic equilibrium for loci of studied genes: x2 value for all studied loci was 0,008 – 1,96. Analysis of milk producing ability data in groups with different genotypes by locus of CSN3 gene showed that the highest indexes of milk yield were stated for group of cows with genotype CSN3**aa. Animals with genotype CSN3**bb had the highest fat percent, animals with genotype CSN3**aa - the lowest. Analysis of milk yield indexes showed that animals with homozygous genotypes BLG**aa and BLG**bb showed lower average milk yield than animals with genotype BLG**ab on 130 and 570 kg, respectively

Determination of influence of polymorphism of gene of erythropoetin receptor (EPOR) on productive qualities of sows and reproductive characters of boars of Belarusian meaty breed was realized in the conditions of the Republic of Belarus. Research results proved the possibility of EPOR gene application as a genetic marker which determined productive abilities of swine of Belarusian selection breed. Frequency of undesirable allel EPOR**c of EPOR gene in the analyzed swine stock balanced within the frames of wide range: from 44% for Belarusian meaty breed sows up to 78% for Belarusian Kripnaya Belaya breed sows. Analysis of influence of genotype with EPOR gene on multiple fetation of sows of Belarusian meaty breed showed that sows with the preferred genotype (EPOR**tt) statistically reliable (P less than 0,01) exceeded sows with undesirable genotype (EPOR**cc) in accordance with number of alive birth piglets on 1,7 heads. Among sows of Belarusian Kripnaya Belaya breed with genotype EPOR**ct there were stated multiple fetation indexes exceeding the sows with genotype EPOR**tt on 0,5 heads. Desirable EPOR**tt genotype irrespective of sow age rendered the positive influence on their multiple fetation. It was recommended to realize genetic testing on determination og polymorphism of gene of erythropoetin receptor among the animals of Belarusian meaty and Belarusian Kripnaya Belaya breeds. Selection of parental pairs of the selection nucleus was recommended to realize taking into consideration genotypes, giving preference to animals with EPOR**t allel

Growth and development of mixed bred Charollais x white-and-black young stock and black-and-white bull-calves since 8-month old age till and 15-month old age were studied in the conditions in the Republic of Belarus. In course of studied there were analyzed linear growth; young stock growth intensity; forage consumption; efficiency of experimental results. On the basis of obtained data there was determined the absolute growth rate of bull-calves at certain growing periods. Research results showed that dramatic changing of technology of management and feeding of mixed bred Charollais x white-and-black young stock bulls after weaning period caused the decrease of daily average live weight gain from 8-month old age till and 15-month old age in comparison with white-and-black cattle on 99 grams or 14%. Analysis of exterior of experimental animals confirmed the priority of mixed bred young cattle over white-and-black herdmates. They were characterized by massive corpus, wider and deeper barrel, wide withers, back and coupling

Evaluation of amino-acid, mineral, and vitamin content, as well as indexes of meat safety obtained from young stock of cattle of different genotypes in accordance with possibility of its application as raw material for baby food production was realized in the conditions of the Republic of Belarus. In course of study there were used bull calves of white-and-black breed, Limousin breed and their crossbreeds. Research results showed that young stock of Limousin breed, Limousin x white-and-black crossbreds, and white-and-black breed (control group) gave high quality meat. In meat of animals of experimental groups there was stated high quality of almost all nonessential amino acids and nonreplaceable amino acids, in meat of crossbreeds there was noted considerable increasing of polyunsaturated fatty acids. In it there was 12,31% of linoleic acid against 4,75 in Limousin breed and 2,77% in white-and-black breed; and eicosatetraenoic acid – 2,4% against 1,24% and 0,7%, respectively. Also in meat of experimental bull calves there was stated higher content of vitamins, calcium and phosphorus, while the content of cuprum and zinc decreased