COMPARATIVE HISTOMORPHOLOGY OF DIGESTIVE SYSTEM AND ENZYMES IN Johnius belangerii

Johnius belangerii have high economic value in the Persian Gulf. In this research the differences in histological and enzymatic of digestive tract in  Johnius belangerii as a carnivore diet was studied. For this purpose, 10 fish were collected from the beach of Persian Gulf. Then, tissue samples from first and end of the esophagus , stomach and  intestine along with middle of intestine were carried out. Also for enzyme samples the first and end of the stomach and intestine along with middle of the intestine were removed from the gastrointestinal tract. Rutine  procedure of tissue preparation including fixation, dehydration with ethanol, clearation with xylene, blocking with paraffin and cutting with microtome as a thickness of 5 microns were done. After clearing of slides, studied by light microscope. Results showed the length of intestinal villi in the first part of the intestine was more than other parts (p≤0.05).  Also intestinal mucosal cells increased from the primary to the end. There was no significant difference in histological observation. In enzyme samples the activity of the amylase that breaks down carbohydrates in food and alkaline phosphatase activity was high in other species more than Johnius belangerii (p≤0.05). Also lipase activity that breaks down lipids in Johnius belangerii was higher than from species that reported by some researchers (p≤0.05).

Keywords: Histomorphology, Digestive system, Johnius belangerii