Composição centesimal do conteúdo do trato gastrintestinal e atividade enzimática digestiva de teleósteos

Abstract

The aim of this study was to evaluate the relationship between the digestive enzyme activity and the centesimal composition of the contents of the gastrointestinal tract and food habits of four teleost two food habits in summer and winter. Two omnivorous species Pimelodus maculatus and R. quelen and two detritivorous species Hypostomus commersoni and Loricariichthys anus were chosen. Fish were collected with the aid of the trawl during March and July 2013 in São Gonçalo channel, Pelotas - RS. The digestive tract was divided into stomach, anterior and posterior intestine. Stomach was assayed the activity of pepsin and the two portions of the intestine were assayed the activities of trypsin, chymotrypsin and lipase. The protein and lipid content of the contents of each portion of the digestive tract was determined. Digestive enzyme activity is not related to the feeding habits and the centesimal composition of the contents of the gastrointestinal tract. Detritivorous species showed higher activity of alkaline proteases, which may be an adaptation to better utilize the low protein content found in the gastrointestinal tract of these species.