Determination of the efficiency of young fat stock feeding with wet rolled maize grain which was preserved by means of different preparations was realized in the conditions of the Republic of Belarus. The following preserving agents were applied: HV-2 (by- product of amino-formaldehyde resin); AIV 3 Plus (mixture of 62% formic acid and 24% ammonium formate; KEMIRA, Finland); carbamide (30 kg/t) with 40 g/t of complex mineral supplement. Feeding of young fat stock with rolled maize grains preserved by NV-2 promoted the increasing of nutrient digestibility on 1,5-5,0%, nitrogen use - on 2% in comparison with control. Application of rolled maize grain preserved with AIV-3Plus and carbamide with the complex mineral supplement made it possible to increase the digestibility of nutrients on 1,0-4,8% and nitrogen use - on 1,6-1,7%. Introduction of rolled maize grain preserved with NV-2 into rations of bull calves increased their productivity on 4,7% (P less than 0,05) with the simultaneous lowering of forage expenses on 1,9%. Application rolled maize grains preserved with AIV-3Plus made it possible to increase daily average weight gain on 3,8% and lower the forages expenses on 2,6%. Use preserved with NV-2 and AIV-3Plus rolled maize grains in rations of young fat stock lowered the production cost price on 11,9% and 10,8% that proved the efficiency of the studied fodder

Evaluation of maize (Zea mays) silage prepared in combination with biological preserving agent Laktotim and calculation of its economic efficiency were realized in the conditions of the Republic of Belarus. Application of Laktotim rendered positive influence on forage dry matter content, on nutritive substance safety, and made it possible to increase the organoleptic indicators of silage. Use of the maize silage prepared with the preservative in a cow ration has positively affected their dairy efficiency. Cow milk yields have raised on 4,5%. Application of the preparation for silage making of green maize mass proved to be economically worth. The realized toxicological estimation of biological preserving agent Laktotim did not reveal any signs of preparation toxicity. Introduction of the preparation into mice stomach in a single maximum dose (25000 mg/kg; 12500; 5000 mg/kg of body weight), as well as application of the preparation in mixture with water in ratio which in 100 and 200 times exceeded the standard ratio in plant green mass, did not cause destruction of experimental animals. According to classifications of All-Union State Standard 12.1.007-76, the preparation Laktotim belongs to the4 class of danger - low-hazardous substances (LD50 over 5000 mg/kg)

Nowadays in connection with an interdiction for antibiotics use in animal feeding it is very actual to work out and apply new forms of probiotic preparations which should be as ecologically safe and harmless both to people and animal products. Probiotics make it possible to improve the digestibility of nutritive substances of forages, normalize metabolism, enrich with biologically active substances that promotes the increasing of their productivity. In the Republic of Belarus the probiotics are produced in the obviously insufficient quantity that creates problems of young stock livability. Influence of application of Akozil and Sublicin probiotics in diets of suckling calves on biochemical parameters of blood serum was analysed. It was stated that use of the analysed probiotics made it possible to decrease the level of urea and total cholesterol, to increase of the total protein content in blood serum of the experimental calves. There was noted the increasing of glucose level in blood serum of calves fed with Akozil. There was marked the tendency of more optimal level of calcium and phosphorus in calves having Sublicin in their diets. The obtained results testified the normalization of metabolic processes taking place in calves which were fed by the mentioned above probiotics

In the conditions of the Republic of Belarus there was studied rumen digestion of ruminants after their feeding with green mass of buckwheat (Fagopyrum esculentum) and buckwheat haylage. Special attention was given to studying of enzymatic processes taking place in rumen. The experiments were realized in vitro with application of simulator Rusinec (Rumirant Simulation Technique) for the imitation of digestion processes taking place in cattle rumen. On the Rusinec (n=4/diet) stimulator there were analyzed 5 rations on the basis of hay with buckwhear addition in dose of 0,300 or 600 g/kg on the form of green mass and haylage. None of the above mentioned forms of buckwheat in vitro experiments rendered negative influence on rumen digestion and concentration of volatile fatty acids. Application of buckwheat green mass made it possible to lower the quantity of bacterium in rumen content; while buckwheat haylage – the number of protozoon organisms. There was marked a tendency to lowering of fleshed methane.

In the conditions of the Republic of Belarus there was studied the influence of various doses of kizelgur on metabolic processes and natural resistance of poultry by an example of lying hens. Use of the mineral additive rendered the positive influence on protein, carbohydrate, lipidic and mineral metabolism in hens. It was marked that in blood the content there was an increasing of crude protein on 11,5-11,7% (Р less than 0,05), crude lipids - on 1,9-5,3%, glucose - on 25,1-54,6% (Р less than 0,01), calcium - on 0,8-12,4%, phosphorus - on 8,9-15,9%, iron - on 9,2-24,6% (Р less than 0,01) and magnesium - on 9,3-21,6%. The laying hens which were fed with the mineral kizelgur additive were characterized by better resistance reactions. Bactericidal activity of blood serum of the experimental hens was higher on 2,7-15,3% (Р less than 0,01), lysozymic activity - on 1,3 22,5% (Р less than 0,05).

In the conditions of the Republic of Belarus there were studied the productive and interior indexes of bull calves which were fed with dried distiller's grains. Inclusion into bull calves diets of the mixed fodder containing 33% of dried distiller's grains made it possible to increase the concentration of volatile fatty acids on 16-18%, albuminous nitrogen - on 4-7%, quantity of infusorians - on 16-17%, as well as to reduce the ammonia level in a ruminal liquid from 23,4 up to 17 mg%. Inclusion of 33% of dried distiller's grains into structure of mixed fodder and feeding the same quantity of fresh distiller's grains promoted increasing of nutrient digestibility on respectively 4,0-5,9% and 3,5-4,5%, nitrogen retention - on 13%. Increasing of level of dried distiller's grains in structure of grain forage up to 67% increased the digestibility of nutrients on 1,5-2% and nitrogen retention - on 4%. Substitution in mixed fodder for bull-calves of 33 and 67% of fodder grain by dried distiller's grains made it possible to increase daily average live weight gain of animals respectively on 10 and 4%. Feeding of dried and fresh distiller's grains at simultaneous introduction in rations of complex mineral additive promoted the activation of metabolic processes that was proved by increasing of crude protein of blood at 6-7% and 5-8%, as well as decreasing of concentration of urea - on 25 and 22% respectively. Use of 33% of dried distiller's grains as a part of mixed fodder for cattle young stock proved to be economically effective and allowed to lower the cost price of a live weight gain on 10-11%. Feeding with fresh distiller's grains allowed to lower the prime cost price on 7% and to receive additional profit.

In the conditions of the Republic of Belarus there was analyzed the efficiency of application of an adsorbent mycotoxins Toxfin Dry (Belgium) for lowering of toxicity load on broiler chickens. In the course of the study there was given attention to poultry productivity, viability and forage expenses for broiler chickens breeding. There was developed a scheme of Toxfin Dry preparation feeding to broiler chickens. There were presented the results of weighing of control and experimental broiler chickens during the breeding periods; the basic zootechnical indices in the conditions of introduction Toxfin Dry; economic efficiency of its application. Research results showed that introduction of a mycotoxin adsorbent Toxfin Dry into diets of broiler chickens promoted the improvement of digestion and absorption of mixed fodder nutrients in a gastroenteric tract, that in its turn promoted the increasing daily average weight gain on 4,3%, broiler stock viability - on 2,6%; and to decrease the expenses for forages on 13,9%. On the basis of obtained experimental data it was recommended to include the mycotoxin adsorbent Toxfin Dry into rations of broiler chickens as a dry mix with mixed fodder in a dose of 5 g/kg of forage dry matter.

In the conditions of the Republic of Belarus there were analyzed the efficiency of application of a new mineral additive produced of the basis of carnallite brine (the national local raw material) as a part of mixed fodders for feeding of young stock of cattle. There was analyzed its influence on digestibility of a diet nutrients in cattle rations and on animal productivity. Inclusion of carnallite brine in mixed fodders structure for fattening young cattle rendered a positive influence on forage palatability. Forage consumption on a per head basis increased on 5,4%. Optimum dose of addition of carnallite brine in mixed fodder - 0,85%. Feeding of young cattle with the experimental mixed fodders did not render negative influence on hematological indices and physiological condition of animals. Use in young cattle rations of the mixed fodder containing 0,85% of carnallite brine promoted the increasing of nutrient digestibility on 3,4-5,7%. In the conditions of feeding of mixed fodders with other doses of carnallite did not cause any changes in digestibility of nutrients. Feeding of the prepared mixed fodder with 0,85% of carnallite brine to young growth of cattle made it possible to increase the growth energy on 5%.

In the conditions of the Republic of Belarus there was analyzed the efficiency of feeding of a new protein vitamin and mineral additive containing national local protein and mineral raw material sources in diets of 12-16-month old heifers. Instead of sunflower extraction cake the heifers were fed with the protein-vitamin and mineral additive which contained rape grain (Brassica napus), lupine (Lupinus) grain as well as mineral and vitamin additives based on halites, phosphogypsum, phosphate, sapropel and premix in dose of 20-25% by weight as a part of mixed fodders. The additive was used against the background of rations with green mass from a cereal and leguminous mixture - 56-57%, mixed fodder - 36-37%, molasses - 6-7%. In accordance with nutritional value indexes the proposed additive rendered the positive influence on forage consumption, indexes of ruminal digestion, as well as on the morphological and biochemical blood composition. It application made it possible to obtain daily average weight gains of animals at the level of 812-827 grams within forage expenses of 7,0-7,2 сentner of fodder units. Inclusion of the protein vitamin and mineral additive with local protein and mineral raw materials in rations of calves made it possible to lower the mixed fodder cost price on 12-15% and the cost price of 1 centner of gain during the summer period - on 11-13%.

In the conditions of the Republic of Belarus there were determined the fattening and slaughter qualities of swine as well as the evaluation of their pork production in the conditions of inclusion into their diets of a biologically active substance on the basis of field caraway (Carum carvi L.). Research results showed that in the production conditions the administration of the biologically active additive in a dose of 7 gram per 100 kilogram of live weight of pigs made it possible to increase their daily average gain from 627,9 grams in a control group up to 687,2 grams (or on 9,44% (P less than 0,999)), to increase their preslaughter and slaughter weight respectively on 3,76% and 6,42%, dressing percentage and carcass yield – respectively on 1,71 and 1,67%. According to the indexes of meat quantity in diverting weirs of the experimental pigs surpassed the control group on 3,03%, or 2,70 kg. The fat content in the half carcasses of the experimental group was authentically lower than the indices of control animals on 0,48 kg or on 2,18%. The hock weight of experimental animals with high confidence exceeded pigs of the control group on 1,15 kg, or on 10,45%. They practically did not differ from the control group according the indexes of thickness of pork fat at the level of 6-7 chest vertebras, and in the area of a muscular eye surpassed them on 4,0 square сm or on 7,72%.