Analysis Of The Quality Difference And Mechanism Of Adult Carassius Auratus Gibelio From Three Different Aquaculture Modes

In order to explore the mechanism that affects the differences in the quality of adult gibel carp Carassius auratus gibelio from different aquaculture modes,this study adopted the method of comparative analysis,from the aspects of the morphological and quality characteristics,body color,muscle texture,muscle nutrients,organ functional enzyme activity and serum biochemical indicators,compared the differences in the three modes,named pond monoculture（M1）,pond polyculture（M2）with Litopenaeus vannamei,and reservoir culture（M3）.（1）Differences in morphological and quality characteristics:The three aquaculture modes of adult gibel carp had a well distinction in morphology and quality.The PCA results of the use of the morphological and quality characteristic variables,in which the first two components had a common contribution rate of 69.041%.That is,only PC1 and PC2 can almost explain all the changes in the morphology and quality of gibel carp;the first 8 highest variables selected by the stepwise method were exactly the morphological characteristics,namely maximum depth,head width,eye diameter,caudal peduncle length,caudal peduncle depth,body depth at the dorsal-fin origin,ventral distance and head length in front of the eye,and the comprehensive discrimination accuracy correction ratio was 84.4%,indicating that people could quickly know the aquaculture source based on a simple combination of morphological indicators.（2）Differences in organoleptic indicators and nutritional components:There were certain differences in skin color and back muscle texture between M1 and M2 fish.The nutrition and flavor of the dorsal muscles were approximately the same,while M3 fish were distinguished in all aspects.That is to say,the gibel carp breeding in reservoirs are the best in organoleptic evaluation and nutritional composition,followed by the polyculture mode.（3）Differences in organ-related functional enzyme activities:Na⁺-K⁺enzyme activity of liver ATPase was M1≈M3>M2（P<0.05）,Ca²⁺/Mg²⁺enzyme activity revealed M1≈M3<M2（P<0.05）;There was no significant difference in the average value of the three antioxidant enzymes measured in the heart（P>0.05）.In the liver,there was no significant difference in SOD enzyme（P>0.05）,POD enzyme presented M1≈M3<M2（P<0.05）and CAT enzyme was M1<M2<M3（P<0.05）.The POD enzyme in the gills was M1>M2>M3（P<0.05）,the SOD enzyme was M1≈M3<M2（P<0.05）,and the CAT enzyme showed M1≈M2>M3（P<0.05）;the intestinal amylase activity was M1≈M2>M3（P<0.05）;liver microenzyme activity was M1≈M2<M3（P<0.05）;pepsin activity was M1<M2≈M3（P<0.05）.（4）Differences in 21 serum biochemical indexes:ALB,TP,TCH,TG,GGT,LDH,CK,LPS,LDL-C,K,P those 11 indexes had no significant difference among the three（P>0.05）,ALT,CR,and CO₂ showed M1≈M2<M3（P<0.05）,HDL-C and CL showed M1≈M2>M3（P<0.05）,AST showed M1≈M3>M2（P<0.05）,CA showed M1>M2≈M3（P<0.05）,UREA showed M1<M3（P<0.05）and M2 was not significantly different from it（P>0.05）,GLU-O showed M1>M2（P<0.05）,and M3 was not different from both（P>0.05）,NA showed M1>M3（P<0.05）and M2 was not different from them（P>0.05）.