Effects Of Replacement Of Fish Meal By Fermented Soybean Meal In Diets On Growth,Immunity And Intestinal Tissue Of Carassius Auratus

In order to explore the influence of replacement of fish meal by fermented soybean meal on Carassius auratus [initial mean weight,(9.91±1.10)g] on growth performance, digestive enzyme activity, protein metabolism, nonspecific immune and the intestinal tissue.Five isonitrogenous and isocaloric diets with fish meal replaced by fermented soybean meal of 0.0%(control), 17.5%, 35.0%, 52.5%, 70.0% respectively were formulated. Fish meal and fermented soybean meal were used as the a protein source. Dextrin and flour were used as a carbohydrate source. Corn oil and fish oil were used as the fat source. Cellulose was used as filler. 300 fish were randomly divided into 5 groups,each group has 3 repeat. After 15 days raise,each diet was fed to Carassius auratus for 8 weeks.The results show: 1.Effects of replacement of fish meal by fermented soybean meal in diets on growth, feed utilization and muscle nutritional composition.The feed efficiency ratio of Carassius auratus in 35.0%, 52.5% and 70.0% groups were significantly lower than that in control group(P<0.05). The specific growth rate, protein efficiency ratio and final body weight of Carassius auratus in 70.0% groups were significantly lower than that in control group(P<0.05). no significant differences was abserved in the moisture, crude lipid, ash content and crude protein in muscle of Carassius auratus in treatment groups(P>0.05). 2.Effects of replacement of fish meal by fermented soybean meal in diets on digestive enzyme activity and protein metabolism.The activities of protease in hepatopancreas, midgut and hindgut were significantly lower than that in the control group(P<0.05), when the replacement ratio was 35.0%, 52.5% and 70.0%. The activities of protease in foregut of 52.5% and 70.0% groups were significantly lower than that the control group(P<0.05).The amylase and lipase vigor of Carassius auratus was not significant(P > 0.05). When replacement ratio is 35.0%, 52.5% and 70.0%, the cereal third transaminase in hepatopancreas were significantly reduced(P < 0.05); the cereal third transaminase activity in hepatopancreasin was not significant(P > 0.05). 3.Effects of replacement of fish meal by fermented soybean meal in diets on nonspecific immunity.In 52.5% and 70.0% groups, the super oxide dismutase(SOD) activity and lysozyme activity in serum of Carassius auratus were significantly lower than that in control group(P<0.05); the alkaline phosphatase activity was significantly higher than that in control group(P<0.05). 4.Effects of replacement of fish meal by fermented soybean meal in diets on the intestinal tissue.When fermented soybean meal replace 52.5% and 70.0% fish meal, the midgut was significantly reduced(P<0.05); When fermented soybean meal replace 70.0% fish meal, the hindgut intestinal plica was significantly reduced(P<0.05).The intestinal quality, index of intestine length, intestine body and height of proximal intestine plica were not significantly affected by the replacement of fish meal by fermented meal with the control group(P > 0.05).In conclusion, there was no sinificant difference in the effects of fish meal replaced by fermented soybeanmeal on growth, nutrition components of muscle, nonspecific immune and intestinal structure of Carassius auratuswas when the replacement ratio was lower than 52.5%.