Effect Of Feeding Habits Dometication On Intestinal Microflora,Gut Structure And Function Of Mandarin Fish(Siniperca Chuatsi)

Mandarin fish(Siniperca chuatst)is a characteristic ferocious carnivorous fish in C hina,their feeding habits peculiar that require live fish as bait since initial feeding,and require live fish for food in lifetime.Although the research of feeding with artificial diet in mandarin fish had been made headway,the ingestion performance with artificial diet and ice fresh bait was very different between accept the dead fish(SC_X)individuals and refuse dead fish(SC_W)individuals of mandarin fish This study analyzed the intestinal microbe composition and diversity,gut structure and intestinal function of accept the dead fish individuals and refuse dead fish individuals.We also explore the influence mechanism of artificial diet on intestinal digestion,metabolism and gut microbes in mandarin fish,to study the adaptation mechanism of gut microbes for diet change and the influence of artificial diet on the mandarin fish intestinal environment.1 The difference of gut microbes in the SC_X individuals and SC W individuals of mandarin fish(Siniperca chuatsi)The main purpose of this study was explore adaptation mechanisms of microbial for feeding preferences through the analysis of gut microbes differences between accept the dead fish individuals(SC_X)and refuse dead fish individuals(SC_W)of mandarin fish.We compared the gut microbes and diversity in SC X individuals and SC_W individuals.The result showed that the dominant bacteria in SC_X intestinal sample were Cetobacterium,Reyranella and Plesiomonas,while Pseudomonas,Chloroplast_norank,Lactococcus,Stenotrophomonas,Plesiomonas,Enterococcus,Bacillus and Acinetobacter occupied the dominant position in SC_W intestinal.The intestinal microbial diversity of SC_X group was significantly higher than SC_W group(P<0.01).The sample cluster analysis showed that some sanples of control group were gathered for a group with SC_X,while some other samples were gathered for a group with SC_W.The gut structure analysis showed that intact gut internal structure in SC_X group,while SC_W individuals gut showed there were slight damage.The result suggested that the SC_X individuals and SC W individuals were existed in natural population,and the intestinal microbes were significantly different in SC_X individuals and SC_W individuals.These results suggested that the intestinal microbes had played a certain action in mandarin fish feeding preference.2 The influence of different baits on intestinal microbes and gut structure and function in mandarin fish(Siniperca chuatsi)To explore the influencing mechanism of different baits on mandarin fish intestinal,we analyzed the difference on intestinal microbes,and gut structure and function of fish individuals feed with live bait fish and artificial diet.The results showed that the intestinal microbes of individuals feed with artificial diet(SC_F)were very single,the dominant bacteria were Cetobacterium,Plesiomonas and Aeromonas.While the Bacillus,Lactococcus,Oceanobacillus,Pseudomonas and Enterococcus etc.which belong to Firmicutes and Proteobacteria occupied the dominant position in individuals of Control group.Obviously,the diversity of intestinal microbes in SC_F individuals was lower than the diversity of intestinal microbes in control individuals.In this study,ice fresh bait was made by live baitfish.There was no difference in nutritional ingredients,except the ice fresh bait had been frozen,that may bring no significantly influence on mandarin fish.Therefore,ice fresh bait could not affect fish intestinal microbes and gut structure by different trophic factor compared with control group.According to the results,artificial diet had made some damage on mandarin fish intestinal function,moreover,artificial diet would lower the activity of intestinal digestive enzyme.Due to the abundant of bacteria which secreted the digestive enzymes in mandarin fish intestinal after food change,the intestinal digestive enzyme activity elevated significantly(P<0.05)in intestinal of SC X group.The result meaned that present artificial diet could not meet the digestive requirements of digestion in mandarin fish,but also could not maintain intestinal health in mandarin fish.These results suggested that we should consider balance the digestive requirements and intestinal health in mandarin fish when improving the mandarin fish artificial diet.