Effects Of Replacement Of Fish Meal Protein With Soybean Meal And Extruded Soybean Meal On Growth,Activities Of Protein Metabolism Enzymes And Intestinal Tissue Of Rhynchocypris Lagowskii Dybowski

To explore the effects of replacement of fish meal protein with soybean meal and extruded soybean meal on growth,activities of protein metabolism enzymes and intestinal tissue of Rhynchocypris lagowskii Dybowski,the juvenile fish of Rhynchocypris lagowskii Dybowski with the initial weight(6.81±0.19)g/tail and(6.87±0.02)g/tail were fed five isonitrogenous and isocaloric diets containning 0.0%,12.5%,25.0%,37.5% and 50.0% soybean meal and extruded soybean meal to replace fish meal for 8 weeks.The results were showed as follows:1.Effects of replacement of fish meal protein with soybean meal and extruded soybean meal on growth,feed utilization and muscle composition of Rhynchocypris lagowskii DybowskiFinal body weight(FBW),protein efficiency radio(PER),deposition protein value(PPV),specific growth rate(SGR),weight gain rate(WGR),feed efficiency radio(FER),crude protein decreased in soybean meal and extruded soybean meal group.FBW,WGR,SGR,PER,crude protein content were significantly lower than the control group when the soybean meal replaced fish meal were 37.5% and 50.0%(P<0.5),PER and FER were significantly lower when the soybean meal replaced fish meal was 50.0%(P<0.05).FBW,PPV,SGR,WGR,FER,crude protein were significantly lower when extruded soybean meal replaced fish meal was 50.0%(P<0.05).2.Effects of replacement of fish meal protein with soybean meal and extruded soybean meal on activities of digestive enzymes and protein metabolism enzymes of Rhynchocypris lagowskii DybowskiThe protease activities of hepatopancrea and distal intestine were significantly lower in the 37.5% and 50.0% group(P<0.05),the protease activities of proximal intestine and middle intestine were significantly lower in the 50.0% group(P<0.05).The activities of glutamic oxaloacetic transaminase(GOT)and glutamic pyruvic transaminase(GPT)decreased with the increase of soybean meal replacement,showed a significant lower when the substitution ratio were 37.5% and 50.0%(P<0.05).The protease activities of proximal intestine,distal intestine and hepatopancrea were significantly lower in the 50.0% group(P<0.05).The activities of GOT and GPT decreased with the increase of extruded soybean meal,50.0% group was significantly lower(P<0.05).3.Effects of replacement of fish meal protein with soybean meal and extruded soybean meal on non-specific immunity indexes of Rhynchocypris lagowskii DybowskiWith the increase of soybean meal,the activities of superoxide dismutase(SOD)and lysozyme(LZM)in hepatopancreas decreased,showed a significant lower in 37.5% and 50.0% groups(P<0.05).With the increase of extruded soybean meal,the activities of SOD and LZM in hepatopancreas decreased,50.0% group was significantly lower(P < 0.05).Alkaline phosphatase(AKP)in all groups showed no significant difference(P>0.05).4.Effects of replacement of fish meal protein with soybean meal and extruded soybean meal on intestinal tissue of Rhynchocypris lagowskii DybowskiWhen soybean meal replace 37.5% and 50.0% of fishmeal,the fold height of proximal intestine,middle intestine and distal intestine were significantly lower(P<0.05).When soybean meal replace 50.0% of fishmeal,intestine body weight were significantly lower(P<0.05).When extruded soybean meal replaced 50.0% of fishmeal,the fold height of proximal intestine,middle intestine and distal intestine were significantly lower(P<0.05).