Characteristics of physics and chemistry of digestive organs and effect of pH values on activities of digestive enzymes in silurus Lanzhouensis Chen

Characteristics of digestive organs and the effect of pH values on activities of digestive enzymes in silurus Lanzhouensis Chen were studied.The result showed that,The ratio of intestine length to body length was 0.91±0.25,while the ratio of stomach,intestine,hepatopancreas and viscera weight to body weight were 0.0158±0.0045,0.0112±0.0054,0.0199±0.0069 and 0.0916±0.0293 respectively.The pH values of stomach,anterior intestine,middle intestine,posterior intestine and bile were 5.5～6.5,5.5～7.0,6.0～7.0,6.0～7.0 and 5.5～7.0 respectively.The optimum pH values of stomach,hepatopancreas and intestine for amylase were 5.4,6.6 and 7.0,and that for lipase were 5.4(or 5.8),6.6 and 6.6 respectively.The pH values in stomach and intestine are suitable for amylase and lipase.In the optimum pH value,the amylase activity in hepatopancreas was slightly higher than that in intestine,and that in stomach was the lowest.The lipase activity in stomach was higher than that in hepatopancreas and intestine,while the lipase activity in hepatopancreas and intestine was the same.Considering from the diet composition and character of digestive organs,it could be concluded that the digestive and physical character of silurus Lanzhouensis Chen was conform with the character of carnivorous fish.