In the conditions of the Republic of Belarus there was determined the influence of experimental feed mixtures on the basis of humid preserved grain (conserved rolled grain of triticale; barley (Hordeum vulgare); oat (Avena sativa)) and protein, mineral and vitamin supplement (contains rape (Brassica napus) extraction cake; wheat bran; premix PKR-2; chalk; forage phosphate) on digestibility and metabolism of nutritive elements by young stock of cattle. There were presented recipes of the developed experimental feed mixtures and studied their influence on consumption and digestibility of nutritive elements of diets, metabolism of nitrogenous substances, calcium, phosphorous, as well as on hematological indexes. The proposed mixed fodders contained metabolizable energy; dry matter; crude protein; digestible protein; crude fat; fibre; starch; sugars; calcium; phosphorous; magnesium; potassium; sulphur; iron; copper; zinc; cobalt; manganese. In course of the study there was analyzed the consumption of the main nutritive elements; coefficients of their digestibility; nitrogen balance; balance of calcium and phosphorous; morphological and biochemical blood indexes.

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)

Results of determination of yielding capacity, chemical composition of initial weight and silage quality of forages prepared from the binary mixtures of Japanese millet (Panicum curs-galli var. frumentaceum), millet (Panicum) and saccharine sorghum (Sorghum saccharatum) realized in the conditions of the Republic of Belarus were presented. Research results showed that the binary mixture of saccharine sorghum with blue lupine (Lupinus angustifolius) in ratio of 70% + 30%, respectively made it possible to obtain the highest efficiency (62,4 t/ha of green material, 15,1 t/ha of dry matter, 13,1 t/ha of fodder units). Mixed sowing of millet, Japanese millet and saccharine sorghum with blue lupine surpassed in productivity the single-crop sowing on 15,5-32,6%. It was established, that the silage produced from the mixture of sorghum and Japanese millet with lupine had higher energy and protein nutritive value: 0,86 and 0,98 fodder unit, respectively; 9,77 and 9,92 mJ of exchange energy per 1 kg of dry matter, respectively; 103, 3 and 108,4 grams of digestible protein per 1 fodder unit. High nutritive value and the best palatability of trial silos promoted the increasing of milk yield on 4,4-5,4% in comparison with the control tests. Haylage which was produced from drought resistant crops had high energy nutritive value: per 1 kg of dry matter there was noted 9,40-9,48 mJ of available energy, 0,89-0,94 fodder units with fodder unit provision with 102-114 grams of digestible protein