Production of high-quality beef to a large extent depends on the cattle breed, put on the feeding, the level of full feeding animals and their care and maintenance. The main amount of cattle raised in farms in the western region of Ukraine is repair young and dairy cattle breeds. The best quality beef share from specialized beef breeds in meat balance of the region is relatively small, which respectively leads to further emphasize the development of non-specialized field.

One of the reserves to increase production of quality beef, both in our country and abroad are studying the features of forming meat productivity body fattening animals depending on the power supply. In conducting such research one should more thoroughly examine age biochemical accumulation of all kinds of matter that provide high gain. In this regard, it is important to identify those periods of individual development, when shown the highest rate of growth of muscle, fat, connective tissue and bone, as well as the age period in which biochemical indicators of meat fattening animals are the most desirable.

The main indicator of quality in fattening cattle is fatness. It is known that the overall nutritional value (calories) meat of animals of higher nutritional 2-2.5 times higher than meat cattle with low average fatness. Meat gain from 1 kg of live weight higher fatness in 12-18 kg more than low average. An important factor in increasing production and improving the quality of animal products is qulity feed. The better this resource, the high-grade animal diet will, and therefore better use animal genetic possibilities. Enterprises with dominated stern first class do not allow the production of  third class forage, and save 10-15% of this resource.

This article reflects the results of years of research conducted in the state enterprise sector research "Myklashiv" Western Branch of the National Research Center of the Institute of Mechanization and Electrification of Agriculture of NAAS of Ukraine, in fattening calves Ukrainian black and white dairy cattle from birth to 15 -18 months of age. The main task of the research was to find out the features of growth intensity and meat performance of fattening calves, depending on age and energy security. In this case, the findings of the second phase of research, namely dry matter intake of calves and affordable energy, the study of digestibility of nutrients from the balance of the experiment, the intensity of growth dynamics, assessment of cost-effectiveness of intensive fattening of young cattle. Material for the study were: feed intake, rumen content, performance intensity of growth of experimental animals. To study the biochemical processes in the body of experimental animals from each group of 5 calves rumen contents were taken using roto-pharyngeal probe after 2-2,5 hours after the morning feeding. Rate of growth of experimental calves was determined by weighing the results of the monthly gain, the average and relative increments, and the total cost of feed. Statistical analysis of results of research carried out by the biometric method of MO Plohinskyi and by means of program for MS Excel spreadsheets, MS Office XP package.

It should be noted that the theoretical issue of full feeding of young animals intended for fattening have a different direction and continue to be studied. An important condition of intensive fattening is stable supply needs of the animals in the energy and all nutrients in all periods of growth, establishing the level of energy in the ration supply that provides adequate rate of growth of animals and obtaining the required number of products have 15 months of age. Past studies related to the organization adequate cattle feeding has focused on developing alternative cheaper way of feeding cattle with different fodder, which will reduce the cost of producing beef without compromising with the quality of its performance, because it affects the ability of competitiveness products on the market.

As a result, the following conclusions were made: intensive fattening of calves on diets of moderate energy level (9 months) and high (up to 15 months) provides average fatness animals requires further extension of the duration of feeding. At the same time, moderate level of energy supply (9 months) and high (15 and 18 months) provides higher than average fatness animals. This indicates the high value of this type of feeding that provides adequate rate of growth of animals and obtaining the required number of products have 15 months of age and thus reduces the fattening period for 2 months.

Key words: intensive feeding, bull, power supply, absorption, digestion, nutrients, efficiency, feed factor.