Analysis And Study On The Gut Microbimes Of Tilapia In Different Species And Culture Environment

Gut microbimes are widely present in animal intestines.They not only participate in the digestion and absorption of nutrients by the body,but also assist the host to complete various physiological and biochemical reactions.At present,many studies at home and abroad mainly focus on the impact of gut microbimes on humans and livestock,and there is a lack of systematic research on the microbial structure and diversity of fish gut microbimes.To study the effects of different culture environments and different species in the microbial flora and diversity of tilapia intestines,this experiment designed different culture environments(agriculture in rice fields and pond culture)and different species(Nile tilapia,Olia tilapia,Olia tilapia?×Nile tilapia? and Nile tilapia ?×Olia tilapia?).Through the Illumina Hi Seq sequencing platform,16 S r RNA highthroughput sequencing method was used to explore the diversity and differences in the composition of tilapia gut microbimes of different species and culture environments.The main results were as follows:1.Comparative analysis of gut microbimes in four different species of the tilapia(1)In this study,a total of 45084 OTUs were obtained,and the sequence number: C group(Olia tilapia?×Nile tilapia?)> AN group(Nile tilapia?×Olia tilapia?)> N group(Nile tilapia)> A group(Olia tilapia).Gra Phl An diagram shows that the dominant floras of the experiment fishes were Verrucomicrobia,Firmicutes,Chloroflexi,Planctomycetes,Actinomycetes and Proteobacteria,followed by Fusobacteria,Bacteroides and Acidobacteria.The proportions of these dominant phylums in the gut microbimes of the different species were different,the proportion of Pneumococcus and Proteobacteria was the largest among the four tilapias gut microbimes,and they were 43% and 30% respectively.The experimental results showed that there were differences in the distribution of gut microbimes of different species of tilapia(P>0.05),but it is not significant.(2)PCoA analysis showed that the gut microbimes of the four tilapias were different significantly by the Unweighted,while the weighted showed that four tilapias gut microbimes structures were similar.PCA analysis showed that the gut microbime community composition of the four groups of samples was similar.NMDS method showed that there were obvious differences in the gut mincrobimes of the four types of tilapia.At the genus level,the top four rich species in the gut microbimes of the tilapia were Thermogutta,Spartobacteria?genera?incertae?sedis,Pirellula,Clostridium sensustricto,Mycobacterium and Methylocystis.The proportions of each gut microbime had different changes.The percentage of Thermogutta,Pseudomonas,Spartobacteria?genera?incertae?sedis,and Pirellulain the gut microbimes was similar in the N group tilapia and the AN group tilapia.2.Comparative analysis of gut microbimes of the tilapia cultured in rice fields and ponds(1)A total of 4016 OTUs were obtained in this study,and the sequence number: DT group(rice field)> CT group(pond).At the phylum level,the relatively abundance microflora of Clostridium phylum,Proteobacteria phylum,Paecilomyces phylum,cyanobacteria,and Bacteroides phylum in the gut microbimes in the tilapia of the rice field and pond group.The results showed that the intestinal microbial flora of the tilapia in different culture environments had different composition and distribution.Clostridium phylum had a highest proportion of intestinal microbial flora in the tilapia cultured in rice fields and ponds,and it was 80% and 66.38% respectively.(2)PCoA analysis showed that there was dfferent in the intestinal microbial flora structure in the tilapia of the rice field and pond by unweighted,while the weighted showed that the intestinal microbial flora structure in the tilapia of rice field and pond was similar.PCA analysis showed that the intestinal microbial community composition of the two groups of samples was similar.NMDS showed that there were significant differences in the microbiota of gut microbimes in the tilapia of the rice field and pond groups.At the genus level,Cetobacterium,Paeniclostrdium,Romboutsia,and Plesiomonas were principle in the intestinal microflora of the tilapia cultured in the rice fileds;however,Cetobacterium,Enterovibrio,Plesiomonas,Paeniclostrdium and Romboutsia were in the gut microbimes of the tilapia cultured in the ponds.The proportion of microbial flora in the gut microbimes of the tilapia were different in two different culture environments.Cetobacteri?m had a largest proportion in the two culture environments,and in the rice fields and ponds were 78.84% and 61.80%.The microbial flora in the gut microbimes of the tilapia had a different distribution in different culture environments.