Effects Of Clostridium Butyricum On Intestinal Health Of Procambarus Clarkii

China has become the world's largest producer of Procambarus clarkii,with a mature industrial chain.However,because of the occurrence and prevalence of the disease of Procambarus clarkii,this will still cause a series of adverse effects such as a reduction in the production and a decline in quality of Procambarus clarkii.A lot of practice shows that Clostridium butyricum can improve the micro-ecological balance of animal intestines,promote the healthy growth of poultry,and strengthen its disease resistance,but it is rarely researched and applied in the culture of Procambarus clarkii.To this end,this article carried out the effect of the addition of Clostridium butyricum on the growth performance,health status and intestinal microbiota of Procambarus clarkii.The main results are as follows:(1)Clostridium butyricum has a significant inhibitory effect on common aquatic disease bacteria such as Vibrio Parahemolyticus,Enterobacteriaceae and Aeromonas hydrophila.(2)Adding Clostridium butyricum and sodium butyrate in the feed promoted the growth and feed coefficient of Procambarus clarkii to decrease,which had an improvement effect on its growth performance.But there was no statistical difference,which may be caused by the overall slow growth due to the influence of low temperature.(3)Compared with the control group,the activities of lipase and amylase in the Clostridium butyricum group were significantly increased by 165.84 % and 18.75 %,respectively.and also significantly increased compared with the sodium butyrate group.Although the trypsin activity of Clostridium butyricum group was improved,there was no significant difference.(4)Compared with the control group,the serum CAT,SOD,ACP and AKP in the Clostridium butyrate treatment group increased by 93.07 %,74.12 %,111.14 %and 357.83 %,respectively.Compared with the control group,AKP in the sodium butyrate treatment group showed significant improvement,and there was no significant difference in other indicators.(5)In terms of intestinal morphology,the ratio of villi height and villi height/crypt depth in the posterior intestine of the Clostridium butyrate group was2020 significantly higher than that of the control group,and the crypt depth of the sodium butyrate group was significantly lower than that of the control group.There was no significant difference in midgut between the groups.(6)Through high-throughput sequencing,There were significant differences in flora structure and community composition in different parts of the intestinal tract of Procambarus clarkii both at phylum level and genus level.The dominant bacteria in the midgut were mainly concentrated in two or three species,and the proportion of dominant bacteria in the hindgut was relatively average.Intestinal microbiota diversity of the Clostridium butyrate treatment group were greater than that of the control group and the sodium butyrate group,and the sodium butyrate might decrease.From the phylum level of intestinal microbiota structure,the relative abundance of Proteobacteria and Tenericutes in the Clostridium butyrate group was significantly reduced and the relative abundance of Firmicutes was significantly increased in the midgut and the hindgut.At the genus level,Clostridium butyrate adding clostridium butyrate to the diet can improve the relative abundance of beneficial bacteria and reduce the relative abundance of potential pathogens.Sodium butyrate might slightly increase the relative abundance of potential pathogens.(7)Through genetic function prediction,it was found that more than 50% main function of the intestinal microbiota of Procambarus clarkii is a metabolic function,indicating that the intestinal microbiota should also actively participate in the daily metabolic process of Procambarus clarkii.To sum up,adding Clostridium butyrate in the diet of Procambarus clarkii can regulate the healthy condition of Procambarus clarkii,enhance the antioxidant immune function,improve the digestive enzyme activity in the intestine,improve the intestinal morphology of procambarnacles and regulate the intestinal microbiota structure.