Dynamics of total proteolytic activity of carp intestines when using feed enriched with organomineral chelate complexes

The paper presents data on the total proteolytic activity of the carp intestine when using feed enriched with organomineral chelate complexes. The study of feed additives cannot be reduced to the analysis of zootechnical aspects only, but should be subject to detailed study from the point of view of physiology. Changes occurring under the influence of feed additives in the digestive system are reflected in the assimilation of feed and the productive qualities of fish. The aim of the work is to evaluate the effect of organomineral chelate complexes on the total proteolytic activity of the carp intestine. The total proteolytic activity of the intestinal mucosa (mainly the activity of trypsin EC 3.4.21.4 and chymotrypsin EC 3.4.21.1.) was determined by the increase in tyrosine using the Folin- Ciocalteu reagent (Lenreaktiv, Russia) by a modified Anson method (Anson, 1938). It has been established that the use of the organomineral chelate complex in the studied dosage does not have a negative effect on the total proteolytic activity of the intestine. A reliable increase in the total protease activity of the intestine was revealed when using 1% albumin as a substrate. It is assumed that an increase in the total activity of intestinal proteases will contribute to an increase in feed conversion and will be reflected in an increase in weight gain and profitability of the fish farm. The use of the chelate complex can be recommended for fish in industrial aquaculture conditions.