Effect Of β-Glucan On Non-Specific Immunity And Growth Performance Of Carassius Auratus Gibelio

Carassius auratus gibelio were fed with the diets containing various levels ofβ-glucan (0mg/kg,70mg/kg,210 mg/kg,420 mg/kg, respectively) to determine the effects ofβ-glucan on non-specific immunity and growth. After 65 days, the influence of dietaryβ-glucan were determined by examing non-specific immune functions and growth performance, the capability of resistance to Aeromonas hydrophila were determined 65 days after the fish were fed with diets. The results were shown as the follows:1. For the lysozyme activities in head kidney of Carassius auratus gibelio, 210mg/kgβ-glucan group was significantly higher than the control group (P<0.05). The SOD activities in the hepatopancreas and serum of 70 mg/kg and 210mg/kgβ-glucan groups were significantly higher than the control group (P<0.05). These results suggested that, 210mg/kgβ-glucan group could significantly improve lysozyme activities in head kidney and SOD activities in hepatopancreas and serum of Carassius auratus gibelio, and could significantly improve non-specific immunological function.2. Regarding to the foregut and hindgut ACP activities, there were no obvious differences among allβ-glucan groups and control group (P>0.05), the foregut and hindgut AKP activities of allβ-glucan groups slightly higher than the control group(P>0.05).3. With the increase of supplement ofβ-glucan, the mortality of Carassius auratus gibelio was decreased, and the relative percent survival was increased, the mortality of 420mg/kgβ-glucan group was significantly lower than the other groups(P<0.05), and the the relative percent survival 420mg/kgβ-glucan group was significantly higher than the other groups(P<0.05). These results suggested that,β-glucan supplementation in the dietary of Carassius auratus gibelio could significantly improve the capability of resistance to Aeromonas hydrophila.3. Compared to the control group, the weight gain rate and specific growth rate had no significant difference with supplement ofβ-glucan (P>0.05). The ratio of flesh in whole body, content of crude protein, crude fat, crude ash and moisture in the muscle of Carassius auratus gibelio had no significant difference compared to the control group with addingβ-glucan in the basal diet (P>0.05). And there were no significant difference on the apparent digestibility of crude protein, phosphonium and energy too (P>0.05).