Abstract: To examine the effects of corn gluten meal on lysozyme activity and c-lysozyme gene expression in Fugu obscurus,the fish were fed with diets containing 0%,5%,10%,15% and 20% corn gluten meal in replacement of 0%,7.4%,14.8%,22.2% and 29.6% of conventional fish meal for 60 days,respectively.Lysozyme activities and mRNA levels in the hepatopancreas,head kidney and spleen were examined.The results show that:(1) At the beginning of the experiment,the lysozyme activities of the hepatopancreas,head kidney and spleen were 9.14 U/mg protein,42.12 U/mg protein and 40.49 U/mg protein,respectively.The c-lysozyme mRNA relative expression levels of head kidney and spleen were 3.76 and 3.24 times of the hepatopancreas.(2) Different amounts of corn gluten meal in the diets exerted different effects on the lysozyme activities.The lysozyme activities of hepatopancreas in the 15% and 20% trial groups were significantly lower than that of the control group,and they significantly increased in the 5% and 10% trial groups.In the head kidney,lysozyme activities were significantly enhanced in the 10% trial group,but they significantly reduced in the 15% and 20% trial groups.In the spleen,there were not significant changes on the enzyme activities in the 5% and 10% trial groups,but in the 15% and 20% trial groups,the enzyme activities significantly reduced.(3) Different amounts of corn gluten meals in the diets also resulted in significant changes in c-lysozyme mRNA levels in tissues.In comparison with the control group,the c-lysozyme mRNA expression levels of hepatopancreas significantly reduced in the 15% and 20% trial groups,although they significantly increased in the 5% and 10% trial groups.In the spleen,there were not significant changes on the c-lysozyme mRNA expression levels in the 5% and 10% trial group,but they were significantly lower in the 15% and 20% trial groups than that of the control group.In the head kidney, c-lysozyme mRNA expression levels were significantly enhanced in the 10% trial group,but they significantly reduced in the 15% and 20% trial groups.In a word,the enzyme activities and c-lysozyme mRNA expression levels were peaked in the 10% corn gluten meal group.