Histomorphology and comparison of some digestive enzymes of proper intestine of, Arabibarbus grypus in both warm and cold seasons

For this study 10 Arabibarbus grypus were caught with the same biometric conditions of each sex for two seasons. Then, 0.5 cm long specimen were taken from the anterior, middle and posterior regions of the intestine and placed in Boenchr('39')s solution. Subsequently, routine histological procedure was done and 4-6 µm section, stained with Haematoxylin-Eosin and periodic acid–Schiff. To determine the activity of digestive enzymes, raw enzyme extract was first prepared. The usual steps for measuring enzymes, such as homogenization, centrifugation, and finally were transferred to the autoanalyzer, and results obtained in terms of micromole per milligram of protein were expressed. The results of histological observations indicated that there were four layer of mucusa, submucosa, muscularis, and serousa, like other bony fish. The results of comparing the average activity of digestive enzymes between groups showed that the activity of amylase enzyme in all different regions of the intestine between male and female fish in cold and hot season was not significantly difference (p≥0.05). The activity of the alkaline phosphatase in all areas of the intestine in female increased significantly compared to male fish, especially in the cold season (p≤0.05). Also, there was no significant difference in the activity of lipase enzyme in all different areas of the intestine between male and female in both seasons (p≥0.05). Based on the results of this study, it was found that each part of the intestinal tissue has a structure appropriate to the active digestive enzymes in that area, which has differences and similarities with other species that have been addressed.