Blyusyuk S. Usage of energy of nutritious substances of rations young cattle of aberdeen-angus and volynskaya meat breeds at various levels of power nutrition

Object - bull-calfs and heifers aberdeen-angus and volynskaya meat breeds; the purpose - to study influence of different levels of power supply of young meat cattle on digest of nutritious substances, balance of nitrogen, calcium and phosphorus, gaseous exchange and usage of energy of forages; methods - zootechnikal, physiological, statistical, analytical; the novelty - it is received the new data about the optimal contents of metabolic energy in rations bull-calfs and heifers of meat breeds from 8 to 18-month's age. It is fixed, that at rise of its level on 15 % in comparison with the existing norms digest of organic substance, assimilation of nitrogen and calcium of forages is improved, the barren power loss's are reduced and the efficiency of usage her in an organism is increased; outcomes - from 8 to 18-month's age in calculation on 100 kgs of alive mass bull-calfs aberdeen-angus is improved it is necessary on the average 21,45 MDg, heifers - 35,44, of volynskaya meat breed - accordingly 30,01 and35,18 MDg of metabolic energy, that exceeds the mean data of the norms VASGNIL (1985). Thus on 1 kg of an incremental of alive mass the animals utilize less of metabolic energy and protein; cost of an incremental value of alive mass reduce on 0,5-1,8 %; branch - meat cattle breeding