Effects Of Soybean Meal On The Growth,intestinal Tissue And Non-specific Immunity Of Perca Flavescens

The research object of this experiment is body mass [(3.47±0.03) g] of Perca flavescens, The Perca flavescens was fed the diets that contain 0.0%, 8.0%, 16.0%, 24.0% and 32.0% soybean meal to replace fish meal as semi-refined feed with equal protein(crude protein 42%) and energy(total energy 20.0 MJ/kg). The test was conducted in a controlled temperature single recirculating system for 8 weeks. This study evaluated the effects of partial replacement of soybean meal on growth, activities of digestive enzyme, intestinal tissue and non-specific immunity of Perca flavescens. The results were as follows:1、The effects of soybean meal on the growth, feed utilization and nutritional composition in the muscle of Perca flavescens. When soybean meal had replaced fish meal by 24.0% and 32.0%, the weight gain,specific growth rate, feed efficiency ratioand protein efficiency ratio of Perca flavescens were significantly lower than that in control group(P<0.05). There was no significant differences in viscerasomatic index, condition factor and hepatosomatic index than that in control group(P>0.05). The moisture, crude lipid and ash content in muscle of Perca flavescens had no significant differences(P>0.05). When soybean meal had replaced fish meal by 24.0% and 32.0%, the crude protein concent in muscle of the Perca flavescens were significantly lower than that in control group(P<0.05).2、The effects of soybean meal on activities of digestive enzyme of Perca flavescens. When soybean meal had replaced fish meal by 24.0% and 32.0%, the activities of protease in fore intestine, hepatopancreas and pyloric caeca in Perca flavescens were significantly lower than that in the control group(P<0.05). When soybean meal had replaced fish meal by 32.0%, the activities of protease in Middle and hind intestine in Perca flavescens were significantly lower than that in the control group(P<0.05); When soybean meal had replaced fish meal by 16.0%, 24.0% and 32.0%, the activities of protease in stomach in Perca flavescens were significantly lower than that in the control group(P<0.05). In addition, There were no significant effects of soybean meal on the amylase activities in hepatopancreas, intestinal, stomach and pyloric caeca of Perca flavescens than that in the control group(P>0.05).3、The effects of soybean meal on the intestinal tissue of Perca flavescens. When soybean meal had replaced fish meal by 8.0%, 16.0%, 24.0% and 32.0%, the intestine weight and intestine body weight in Perca flavescens were significantly lower than that in the control group(P<0.05). There were no significant effects of soybean meal on intestine length and intestine length index of Perca flavescens than that in the control group(P>0.05). When soybean meal had replaced fish meal by 24.0% and 32.0%, The foregut, midgut and hindgut fold height were significantly lower than those in the control group(P<0.05).4、The effects of soybean meal on non-specific immunity of Perca flavescens. When soybean meal had replaced fish meal by 24.0% and 32.0%, The activities of superoxide dismutase, lysozyme and alkaline phosphatase in serum of Perca flavescens were significantly lower than those in the control group(P<0.05).All the analysis shows that the activities of digestive enzyme, intestinal tissue structure, growth, non-specific immunity, feed utilization and nutritional composition in the muscle of of the Perca flavescens will not be affected when soybean meal had replaced fish meal were no more than 24.0% in the Perca flavescens.