Research of possibility of application of sapropel (putrid mud) of the Chervonnoe lake (the Republic of Belarus) in diets of bred and milking sows as one of the ingredients of mixed fodders, as well as the evaluation of its influence of sow development and digestibility of nutritive elements were studied. Application of dry sapropel a source of energy, protein, mineral and vitamin nutritive elements for mixed fodder production rendered the positive influence on sows productive qualities: there was stated the increased number of born piglets on o,5 heads with a higher growing capacity; there was noted the increasing of coefficients of nutritive elements metabolism (crude protein – on 2,7%, crude fat – on 2,9%, free-nitrogen extracts – on 1,3%, and dietary fibre – jn 4,7%) with the simultaneous increasing of nitrogen, calcium, and phosphorous uptake by sows. Nutritional value of the analysed sapropel was 0,23 fodder units and 3,13 MJ of exchange energy per 1 kg of dry matter. Inclusion of 3% sapropel into mixed fodders for pregnant and suckling sows promoted the increasing of quantity of pigs at a birth, body weight of one pig to 3-week age and has ensured young growth with higher energy of growth. Use of sapropel in mixed fodders for sows makes active a metabolism and promotes increase of digestibility of the basic nutrients of a rations

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%

Improvement of the standards of energy and protein diets of young stock cattle of 1-6 month old and determination of its influence on animal productivity was realized in the conditions of the Republic of Belarus. The studied made it possible to determine that at the age of 1 month the calf diet should contain 1,02 kg of dry matter and 21,2 MJ of metabolic energy; at the age of 2 months - 1,26 kg and 23,5 MJ; at the age of 3 months - 2,2 kg and 25,6 MJ; at the age of 4 months - 2,9 kg and 31 MJ; at the age of 5 months - 3,28 kg and 34,2 MJ; at the age of 6 months - 3,76 kg and 37,6 MJ, respectively. Metabolic energy concentration per 1 kg of dry matter should not be lower than 20,7 MJ at the first month, 19 MJ - at the second month, after the third month it should lower up to 10 MJ. In course of 6 months the presented diet scheme made it possible get 832 g of average weight gain in the conditions of forage expenses of 3,52 forage units per 1 kg

In the conditions of biogeochemical zone of the Republic of Belarus the most important role in mineral metabolism is played by such major mineral elements as calcium, magnesium, phosphorus, potassium and trace elements - cobalt, cupper, iron, iodine, zinc, manganese, and selenium. Based on the above there was determined the interrelation between the content of these minerals in fodder and blood of milking and dry pregnant cows. As a result of realized study it was found out that the content of major mineral elements and trace elements in fodder did not always correspond to their level in blood. In the conditions of insufficient supply of Ca, F, Mg, K, Fe, Си and Co in cow diets, the level of potassium in blood was lower standard and the other analysed minerals were within the standard limits. There was stated the direct correlation relationship between the level of some biochemical indices and content of mineral substances in cow diets. Positive correlation was stated between the content of calcium and magnesium and cholesterin level in blood

Traditional raw materials in Belarus for mixed fodders production are wheat, barley, oats, rye, peas, lupine, sunflower and rape cakes, bran. However, productive action of these forages is limited because of presence of antinutritious factors and the raised cellulose content. In the Republic of Belarus there was organized production of national enzyme fodder additive Fekord 2004. Peculiar feature of the presented enzyme complex was addition of into its structure of enzyme glucoamylase, promoting hydrolytic starch splitting, and accordingly, the increasing of absorbency of difficult carbohydrates of forages. It was especially important for stores at early stages. Thereupon it was expedient to study the efficiency of application specified multienzyme composition in diets of growing and fattened stores. It was established, that enrichment of mixed fodder with the analysed fodder fermental additive at the rate of 0,13 and 0,15 kg per ton of mixed fodder made it possible to increase the growth rate of pigs and lower charges for forages per unit of body weight gain. Higher economic return on the fodder enzymic additive an additional gain of body weight appeared at its introduction in quantity of 0,15 kg per ton of mixed fodder

Analysis of the efficiency of application of fermented milk supplementary feed DKM (Belarus) produced on the basis of bacteria strain Lactobacilus acidophilus 55/06 in calve diets was realized in the conditions of the Republic of Belarus. Influence of feeding with acidified with the trial milk additive on forage palatability, biochemical blood structure and calve productivity was studied; economic efficiency of DKM use for processing of whole milk and its use in rations of calves was defined. Experimental batches of DKM fermented milk supplementary feed were produced at Grodno Medical Preparations Plant (Belarus). It was issued in the sterile corked polyethylene 5, 10 and 20 liter bottles or canisters. The fermented milk supplementary feed DKM could be stored at the temperature from 0 deg С up to 15 deg С. Shelf-life – 3 months from the moment of production. The additive represents the homogeneous mass of viscous consistence of cream color of various shades with a sour-milk smell. The carried out economic calculations showed, that as a result of growing capacity increase it animals of a trial group and reception of an additional total live weight gain there was stated the 6,5% decrease of expenses for fodder unit production in the experimental group. However, due to a high cost of acidified milk the cost of fodder unit in trial group was on 6,8% higher. As a result, the cost price of 1 kg weight gain in trial group (despite high additional weight gains) was stated at the level of control group. Application of fermented milk supplementary feed DKM in calve diets made it possible to lower calf disease incidence and to increase calf productivity on 11,8% without increasing the cost price of production

Balanced complete feeding proved to be one of the major conditions of animal productivity increase and improvement of their reproductive qualities. Full value of feeding could be obtained at the expense of forage quality improvement and perfection of structure of the rations providing the increasing of metabolic energy use by breeding bull-calves. Analysis of the efficiency of metabolic energy use by the replacement bull calves under conditions of various sugar and protein ratio was realized in the Republic of Belarus. Research results showed that enrichment of replacement bull calves (with 325-405 kg of live weight) rations with easy digestible carbohydrates (sugar and starch) in ratio of 32% from a dry matter ration, including 15% of stable starch made it possible to increase the transformation of metabolic energy into energy of body weight gain on 21,73 - 23,96 MJ or on 10,3%, that as a result correspondingly increased the daily average weight gains on 7,9% and reduced the expenses for forage energy for 7,1% counting on an energy unit. According to the ejaculate volume indices the bull calves of the second experimental group surpassed analogues of a control group on 14,8%, and according to sperm concentration indices - on 12%. The average quantity of the frozen doses of sperm has made 65%

In conditions of the Republic of Belarus much attention is given to optimization of energy and protein content in diets of dry cows. Analysis of the influence of different energy and protein ratio in dry cows diets on their productivity was realized. Increasing of protein and energy balance standards of dry cows during the winter period on 10 and 15% at the expense of introduction of protein, vitamin and mineral supplements (PVMS) made it possible to increase the daily average weight gain of animals on 5,4% and 12,2%, live weight of calves at a birth on 3,6% and 8,1% and their daily average weight gain over the first month - on 3,9% and 12,1%, respectively. Feeding with PVMS produced on the basis of peas and rape made it possible to raise the digestibility of nutritive substance on 1,4-14% and accessibility of all mineral substances on 0,4-10%. The increasing of energy and protein ratio on 15% in diets of pregnant dry cows rendered the positive effect on dairy efficiency. Fodder expenses for fodder unit production decreased on 5,5 and 6,8%, respectively. Inclusion of PVMS in mixture with pea and rape flour for dry pregnant cows during the summer period made it possible to raise their live weight on 5,9% and 9,7%, weight of calves at birth on 4,2% and 7,3%, and their daily average weight gain - on 5,7 and 9,4%. Optimization of power and protein fodder of pregnant dry cows promotes the increasing of milk yields in the first 100 days of the subsequent lactation on 5,1% and 9,9% and the decreasing of forage expenses for production unit on 4,6-9,1%

Studying of influence of various levels of selenium on growth, protein structure of blood serum, natural resistance, and reproductive performance of pedigree bull-calves was realized in the conditions of the Republic of Belarus. It was established, that feeding with an optimum dose of selenium (0,4 mg per 1 kg of dry matter) in rations of replacement bull-calves during the raising period promoted the increasing of daily average weight gain on 6,8%, indexes of natural resistance - on 0,5-13,9%, and sperm production quality - on 4,5-27,3%. In the conditions of optimization of selenium level of in diets the protein structure of blood serum of replacement bull-calves exceeded the similar index at control animals by the crude protein index - on 8,3 (Р less than 0,05), by albumine and alpha globulin -on 2,2% and 1,6%, respectively. Application of selenium in dose of 0,4 mg per 1 kg of dry matter made it possible to increase the indexes of natural resistance on 0,5-13,9%. Increase of selenium dose up to 0,4 mg per 1 kg of dry matter in made it possible to increase the quantity and quality of sperm of bull-calves, that was proved by the increasing of ejaculate volume on 4,5%, concentration of male germ cells in ejaculate – on 15,7% (Р less than 0,05) and male germ cells activity - on 7,3% (Р less than 0,001)

The research directed on perfection of a cattle protein food system, taking into account its fractional structure, and also establishment of objective indicators of an estimation of forage protein nutrient density, have great value. It is established, that for young growth of cattle of 4-6 months of age the optimum parity of decomposable and un-decomposable protein in rations corresponds to size 68:32, allowed to raise digestibility of nutrients on 3-4%, nitrogen adjournment in an organism of animals on 10% and daily average a gain on 4% in comparison with parity 80:20. The optimum parity of fractional structure of protein makes positive impact on oxidation-reduction processes in organism to what testifies morphological-biochemical structure of blood. Thus concentration of crude protein raises on 1,7%, urea quantity decreases on 23%. The least cost price of a gain has appeared in group with a parity of decomposable and un-decomposable protein in rations 68:32, or it is better on 4,4% than an indicator of group with a parity 80:20%