Application of protein, vitamin and mineral supplement in diets of 1-3 months old calves in rate of 5% per weight instead of a part of sunflower cake, containing rape, peas, lupin and vitamid on a basis of halites, phosphite, phosphate, sapropel and a mineral-vitamin preparation in structure of grain forage against winter rations on the basis of rich in herbs hay (5%), milk (68%), mixed fodder (20%), whole grain (7%), and also summer rations with grass and legume mixture (7%), hay (1%), milk (65%), mixed fodder (20%), integral grain (7%) makes it possible to receive daily average weight gain of calves at level 833-867 grams at expenses of forages for 1 centner of weight gain on 3,3-3,4 сentner of forage units. Introduction into rations of the protein, vitamin and mineral supplement on the basis of local protein and mineral raw materials in number of 10% per weight in structure of mixed fodder for calves at the age of 3-6 months old against the background of winter diets with haylage (28%), mixed fodder (64%), molasses (8%), as well as summer diets with grass and legume mixture (30%), mixed fodders (66%), molasses (4%) makes it possible to receive daily average weight gains of calves on 944-967grams at expenses of forages of 4,0-4,1 сentner of forage units. Feeding of 1-6 months old calves with mixed fodders with inclusion of 5-10% of protein, vitamin and mineral supplement per weight with grain high-protein crops against the background of winter and summer diets with a ratio of the deconjugate protein to the non deconjugate one - 65:35 (in control group - 71:29) instead of sunflower cake makes it possible to receive the daily average weight gain at the level of 900-927 grams at expenses of forages 3,7-3,8 сentner per forage unit. Cost of presented mixed fodders decreases on 14%, and the cost price per 1 centner gain - on 7-8%

The immune status of chickens, pigs and calves depends on the content of protective factors in incubatory egg, mother colostrum and timely transfer to their posterity. At young growth in postnatal ontogenesis it is allocated three age immune deficiencies. The first is connected with untimely receipt transovarian and colostoral factors of the protection, the second is caused by an expenditure of passively transferred protective factors of protection and immaturity of own immune system. The third age immune deficiency arises at sharp transfer of young growth into new type of feeding and concerns, first of all, disorders of local protection of a digestive path. Timely application the probiotic enterobifidin, baktril-2, bifidoflorin, developed by Vitebsk State Academy of Veterinary Medicine together with Institute of microbiology of the National Academy of Sciences of Belarus, microbic polysaccharides salmopul and vistimulin, received together with Vitebsk biofactory, and also diamiksan allows to prevent development of immune deficiencies and on their background gastroenteric and respiratory diseases of young growth, to stimulate animal growth and to improve quality of meat production, decrease economic efficiency and ecological safety, considerably allows to reduce application of antimicrobic preparations (antibiotics, Sulfanilamidum, Nitrofuranums, etc.) | Иммунный статус цыплят, поросят и телят зависит от содержания защитных факторов в инкубационном яйце, молозиве матерей и своевременной передаче их потомству. У молодняка в постнатальном онтогенезе выделяется три возрастных иммунных дефицита. Первый связан с несвоевременным поступлением трансовариальных и колостральных факторов защиты, второй обусловлен расходованием пассивно перенесенных защитных факторов защиты и незрелостью собственной иммунной системы. Третий возрастной иммунный дефицит возникает при резком переводе молодняка на новый тип кормления и касается, прежде всего, нарушения местной защиты пищеварительного тракта. Своевременное применение пробиотиков энтеробифидина, бактрила-2, бифидофлорина, разработанных Витебской государственной академией ветеринарной медицины совместно с Институтом микробиологии НАН Беларуси, сальмопула и витстимулина, совместно полученных с Витебской биофабрикой микробных полисахаридов, а также диамиксана позволяет профилактировать развитие иммунных дефицитов и возникающих на их фоне желудочно-кишечных и респираторных болезней молодняка, стимулировать рост животных и улучшать качество мясной продукции, повышать экономическую эффективность и экологическую безопасность, значительно сократить применение противомикробных препаратов (антибиотиков, сульфаниламидов, нитрофуранов и др.)

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 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%.

In the conditions of the Republic of Belarus there was realized a comparative estimation of efficiency of the increased level of phosphorus, calcium, copper, zinc, cobalt, iodine and vitamins A and D in comparison with regulations of the All-Union Academy of Agricultural Sciences of the Soviet Union (1985) and the Russian Academy of Agricultural Sciences (2003) for pregnant cows in a dry period at summer feeding. Also, there was studied the digestibility of nutritive substances of forages in cow diets, as well as the evaluation of their after-effect on revelation of dairy productivity indexes in the subsequent two months of lactation, biochemical blood indexes and payment of forage byproducts. As a result of application of moderately increasing levels of macro- and trace elements, vitamin D, and phosphorus in particular on 10,0% in comparison with 15,0% and existing level in rations of pregnant cows there was stated a slight decreasing of pregnancy duration of animals on 0,10 day. Also, there was marked an increasing of milk yield of milk with 4% fat content on 1,64% and 4,48%, the growth and development of calves in the prophylactic period on 4,18 and 4,61%,; and the was an improvement of organic substance digestibility on 1,52 and 1,78%. Besides, there was revealed more moderate number of leukocytes and content of crude protein.

In the conditions of the Republic of Belarus there was studied the efficiency of application of forage chemical preservatives Kormoplyus-1, Kormoplyus-2, and Kormoplyus-3 for grass fodder conservation. The analyzed preservatives contained acetous acid, urotropine and sodium acetate (only in Kormoplus-2). In course of the study there were established experimental batches with the studied sreservative; there was determined a chemical composition of prepared forages; in physiological and scientifical and economic experiment there was analyzed the feeding efficiency of cereal ensilage. Research results showed that application of preservatives Kormoplyus-1 and Kormoplyus-2 2 for preparation of cereal ensilage made it possible to receive a high quality ensilage and to increase the dry matter safety on 4,2-8,7% and protein on 12-9,4% on comparison with storage without preservatives. Also, it made it possible to increase the digestibility of dry matter in cattle diets respectively on 5.5% and3.7%; organic substance - on 5.5% and 4.0%; fibre - on 16,5% and 15,0%, and also to increase nitrogen deposition on 17,4 and 20,8%. Feeding with forages preserved with Kormoplyus-1 and 2 did not render negative influence on a health state and biochemical indices of animal blood.

Investigation of quality and quantity indexes of sperm production of boars of Yorkshire, Landrace, Duroc breeds of Danish selection was realized in the conditions of the Republic of Belarus. Quality and quantity indexes were analyzed in accordance with ejaculate volume, spermium concentration and activity at different age-specific periods in the comparative aspect. Thorough analysis of quality indexes (ejaculate volume; spermium concentration; spermatozoon motility; sperm quantity) of semen production of studied breeds at different age-specific stages (before 7 months old; 7-10 months; 10-12 months; 12 months and older) was presented. Coefficients of variation of valuation indexes of semen production were stated. Research results showed that the lowest ejaculate volume was typical for boars of Duroc breed, but the quantity of spermium in ejaculate of this breed since 10-month old age was the highest – 92,6 milliard, that made it possible for this breed of boars to take premier place according to the index of spermium quantity in ejaculate. The same index for boars of Landrace and Yorkshire at age of 12 months old and older was 77,5 and 76,3 milliards, respectively. High variability of indexes of evaluation of semen production was due the reason that the research was taking place at the period of formation of productivity over the whole pig stock. Research results proved that indexes of semen production of producer boars of Yorkshire, Landrace, Duroc breeds of Danish selection depended on the breed and high variability indexes

The recipe of mixed fodder is developed for cows with a 6-8 thousand kg yield of milk for a lactation during the period yield of milk, different the raised maintenance of a crude protein (18%) that allows to increase a yield of milk of animals by 6,6% (22,5 kg instead of 21,1 kg of 4% milk a day) to reduce the expense of forages on production unit to 6,4% (0,73 fodder units against 0,78 fodder units per 1 kg of milk). At the expense of additional production economic benefit makes 104,4 thousand rbl. counting on 1 head

It is determined that diets with protein digestibility of 61-66% in organism of a calve activate fermentative processes in rumen, increase digestibility of nutrients at 3,8-10,1% that allows to obtain the average weigh gains of 1036-1075 g, that is at 4,2-8,1% higher than that of control group at forage spends of 6,79-7,04 forage units