Klepach L. The peculiaries of protein digestion and blood metabolites in calves after feeding of native and extruded feeds

Object of research: the investigation of the effect of extrusion of concentrated feeds on the degree o of organic matter and protein break down in the rumen, on protein, amino acids and the product of their catabolism contents in ruminal contents, duodenal chyme and blood of calves of different age and on the intensity of their growth. The purpose of operation: the investigation of the degree of protein break down in extruded and unextruded concentrated feeds and producted from hem mixed feed in rumen of calves of different age in situ and also their effect on age dinamics of proteins, amino acids and products of their catabolism content in ruminal contents, duodenal chyme and in calves blood and on growth intensity. The methods of researches and equipment: biochemical, physiological, zootechnial, spectrofotometr, automatic amino Asid analisator, Keldal, photoelectrocalorimetr, pH-metr. Theoretical and practical results: some aspects of development of ruminal type of nutrition and related to it peculi arities of nitrogen metabolism in the rumen and duodenum of young calves fed by mixed feed prepared from extruded compounds were explaned. New approaches of young cattle feeding that can be used for elaboration of national system of protein nutrition of ruminants were established. With the aim of increase of intensity of calves growth from 1- to 6-months old age the feeding of mixed feed with the high content of undegradable protein that was achived by extrusion of it compounds is recomended. The sphere (area) of utilisation is physiology, biochemistry, cattle husbendry, nutrition.