| The study was aimed at linking different dietary carbohydrate levels to the growth performance and physiological functions of Channel catfish. By feeding the matched pellet feed of different carbohydrate levels (0, 8%, 16%,24%, 32%, 40%) to Channel catfish for 3 months, we got the following conclusion: (1) Under the experimental conditions,with increasing dietary carbohydrate levels, specific growth ratio, weight gain ratio and protein efficiency ratio of test fish
presented the trend of increasing firstly and then decreasing, but feed coefficient ratio presented the trend of decreasing firstly and then increasing. (2) The results of this study showed that, dietary carbohydrate levels had little impact on the crude protein, the crude ash and the moisture content of Channel catfish muscle, but it had a significant effect on the fat content of Channel catfish muscle, and showed a positive correlation with the fat content. (3) Serum glucose concentration,cholesterol content, triglyceride content and total bile acid content showed a positive correlation with dietary carbohydrate levels. (4) In this study, the activity of alanine aminotransaminase (ALT) and aspartate aminotransaminase (AST) showed a positive correlation with dietary carbohydrate levels, however, with increasing dietary carbohydrate levels, the content of alkaline phosphatase (ALP) presented the trend of increasing firstly and then decreasing. Based on the above results, it inferred that the dietary carbohydrate level of 16%~24% was best on Channel catfish juvenile under these experimental conditions.