The effect of addition of Melia azedarach (fruit), Pimpinella anisum (seed), Cuminum cyminum linn (seed), Murraya koenigii (leaves), Emblica officinalis (fruit), Allium sativum linn (bulb), Terminalia arjuna (bark), Sapindus trifoliatus (seed), Zingiber officinale (rhizome), Trigonella foenun-graecum (seed) at three dose level (1.5%, 2.0% and 3.0% of DM) on pH, dry matter and organic matter digestibility of feed was studied with rumen liquor of goat. There was no significant change in the in vitro fluid pH, showing no adverse effect of herb addition. The addition of all the herbs at 1.5% level had no significant (P 0.05) effect on in vitro dry matter and organic matter digestibility. There was slight improvement in dry matter and organic matter digestibility with the addition of Trigonella foenungraecum at 2% level as compared to control. At 3% level of addition of this herb, there was significant (P 0.05) increase in the in vitro dry matter digestibility (%) with Trigonella foenun-graecum (51.97) as compared to control (43.95). Similarly there was significant (P 0.05) increase in the in vitro organic matter digestibility (%) with Trigonella foenun-graecum (54.95) as compared to control (46.87) having with no addition of herbs. So Trigonella foenun-graecum (seed) at 3% dose level can be further explored in in vivo experiment to utilize it as a feed additive to increase the digestibility of feed in goats.

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

Investigation of influence of probiotic Dialact and immunostimulant Alveozan on digesting of nutritive substances by broiler chickens of Kobb-500 cross, as well as control over their individual development were realized in the conditions of the Republic of Belarus. The first (control) group of chicken was given standard well-balanced ration. Chickens of the second group were administrated immunostimulant Alveozan in dose of 10 mkg/kg of live weight with drinking water once a day in course of 5 days, with 10 days interval till the end of the growing period. Chickens of the third group were administrated preparation Dialact in dose of 0,1-0,2 ml with drinking water once a day in course of 3 days, with 14 days interval till the end of growing period. Chickens of the fourth group were given Alveozan in dose of 10 microgram/kg of live weight once a day in course of 5 days with 10 days interval, and Dialact in dose 0,1-0,2 ml once a day in course of 3 days, with 6 and 14 days interval. Research results showed that complex application of probiotic Dialact and immunostimulant Alveozan increased the viability of chickens on 100%, average live weight - on 5,1%, average daily weight gain - on 5,1%. Administration of Dialact and Alveozan, both separately and in complex, increased the digestibility of nutritive substances of mixed fodders: application of nitrogen increased on 1,93-6,38%, application of calcium decreased on 10,41-12,54%, phosphorus use increased on 2,38%

While studying biochemical values that characterize rumen digestibility based on research agricultural experiment some results were obtained. These results prove that studied diets with increase of energy and raw protein concentration levels in dry matter influence positively at nitrous substances concentration activate micro flora motions and promote bio-synthetic processes in rumen fluid of experimental animals

Increase of diets nutrition energy in our experiment showed no significant effect on usage of nitrogen in feeds. Diets with different energy levels have no negative effect on hematological indices of animals

In the physiological experience spent on male pigs-manufacturers, we had been studied influence of various doses of selenium (10 mg, 20 and 30 mg) in structure premix on nutrients. It is established, that increase of level of selenium in mixed fodders for male pigs-manufacturers to 30 mg/kg especially promotes increase in degree of use in their organism of fat to 58,7%; (P less than 0,05), the digested nitrogen to 62,1%, calcium – to 78,3% and phosphorus – to 72,5%

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

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%

In the conditions of the Republic of Belarus there were analyzed the efficiency of 13-18-month old young stock of cattle bred for meat in the conditions of various energy value nutrition levels with the determination of nutrients intake of a diet. It was established that use of rations with various level of metabolic energy and protein breakage rendered the positive influence on nutrient digestibility of rations. This made it possible to improve the digestibility of dry and organic substances, nitrogen-free extractive substances and fibre at the bull calves which were fed with 63% of cleavable protein, as well as to increase the metabolic energy up to 10% in the ration, surpassing the control indexes respectively on 3.1; 2.5; 2.8; and 2.9 items. Adjournment from the acquired nitrogen considerably increased and made up to 64-70%. Productivity of fattening young cattle stock made it possible to obtain 977.7-1011.0 gram of live weight gain. As a result, the growth energy was stated at the level of 15,90-17,33 МJ in the conditions of conversion of metabolic energy into growth of 13,81-14,26% and expenses of metabolic energy of the ration per 1 MJ in live weight gain of 4,72-5,46 MJ.

In the conditions of the Republic of Belarus there were determined the doses of application of siliceous sapropel as well as there were studied the indexes of ruminal digestion and digestibility of diet nutrient substances by bull calves. The studied siliceous sapropel of the lake Pribylovichi (Belarus) occurence on 42% consisted of organic substances and on 58% - of mineral substances: calcium, phosphorus, magnesium, potassium, sodium, iron, zinc, manganese, and copper. The studied sample of sapropel did not render toxic action on test objects of infusorian Tetrahymena pyriformis in the conditions of its addition into the basic forage in number of 1%; 3%; 5%; and 10%. However, its higher concentrations (10%) retarded the development of Protozoa. Feed additives with the content of siliceous sapropel in mixed fodder in dose of 1%, 3% and 5% increased the relative biological value of forage in the experiments on test objects of infusorians Tetrahymena pyriformis in the average respectively on 5,4%, 5,0 and 2,6%. Higher concentrations of sapropel in mixed fodder (5 and 10%) lowered its nutritional value. Inclusion of siliceous sapropel in bull calve rations activated the enzymatic processes in farding bag and increased the digestibility nutritive elements on 2,3-3,6% except for protein, digestibility which was practically at identical level at animals of all groups.