The objective of this study was to evaluate the enzymatic activity of trypsin in the intestinal content of the Thai tilapia male submitted to four different water temperatures. Fingerlings with 0.835 ± 0.004 g initial body weight were distributed in fishbowls with temperatures of 20, 24, 28 and 32ºC. They were fed the same diet and maintained under these conditions until the 55th day of the experiment. The tilapias were removed from the fishbowls and immediately placed on ice for death and to halt the enzymatic activity. The middle and posterior intestines were removed and placed in 2 mL polyethylene flasks. The samples were centrifuged to determine the trypsin activity in the supernatant by using N-Benzoil-D, L-arginina p-nitroanilida (D,L-BApNA) as substrate -and later reading in an optical spectrophotometer. Male Thai tilapia submitted to 32ºC increased tripsin activity and decreased specific tripsin activity.
enzymatic activity; fish physiology; Oreochromis niloticus
