The analysis of data on a complex of reproductive qualities crossing sows has shown, that the combinations used in the classical scheme of variable crossing have appeared are less effective in comparison with the combinations including foreign meat breeds. It is recommended to change the traditional scheme of variable crossing, having excluded from it the Belarus black-motley breed and having entered foreign breeds of L and D and also to use hybrid male pigs (D x P)

Application in diets of breeding bull calves of an optimum dose of selenium (0,4 mg on 1 kg of a solid of a diet) renders positive influence on formation of reproductive ability of bull-calves: promotes increase daily average gains live weight on 7,1%, indicators of natural resistance – on 0,6-6,7% and to improvement of quality sperm production – on 16,4% during the winter period. During the summer period daily average gains live weight on 6,8%, indicators of natural resistance – on 0,5-13,9% and to improvement of quality sperm production – on 15,7% accordingly

The given research results of feeding highly productive cows with new forage supplement of humic-melanoidine nature during the milking period show stable mineral metabolism, correction of their redundant supply within the diet, perfection of digestion and transition into milk as well as minimizing consequences of metabolism intensification. Reception new forage supplement promoted improvement of mastering by an animals organism of necessary iron during the given physiological period, to restriction of mastering of the microelements equal to the category of heavy metals

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

Solution for ecological purity of livestock products that is presented in our research is monitoring of the polluted by heavy metals and radionuclide areas exploration on the aspect of antioxidants content in soils, forages, livestock products and determination of ratio of toxic matters transition into milk

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

Results of researches on studying of efficiency and quality of structure of long-term leguminous-cereal coenoses are presented. Productivity of green weight of a multicomponent mix on the average for five years' use has made 336,0 c/hectares. Economic efficiency of a laying and use multicomponent grass mixture is calculated. At use of a multicomponent mix within five years industrial expenses pay off within 1 year

The comparative analysis of parameters of an estimation of own efficiency of animal Landrace and Yorkshire breeds of the Canadian selection and their descendants has shown, that young pigs of the first generation surpassed the parents in a daily average gain, and in too time conceded on body length and fat thickness

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%

Balancing of mixed feeds for replacement gilts considering the metabolically energy level and essential available amino acids amount increases growth speed of animals at 9,6% (P less than 0,05) compared to mixed feeds prepared in correspondence with detailed norms of feeding; it also decreases terms of animals pedigree usage from 277 to 223 days