A Comparative Study On Intestinal Microbes Of The Hooded Cranes (Grus Monacha) Wintering In Three Lakes Of The Middle And Lower Yangtze River Floodplain

Intestinal microbes of vertebrate participate in host's life activities,and are important for the health of the host.Gut microbiota of animals is affected by both the internal genotype and the external environment of their host.Different sizes and protection level of the habitat provide different external environmental selection pressures for the same wintering migratory waterbird,which may be reflected in their gut microbes.Hooded Crane(Grus monacha)is an international vulnerable(VU)species of migratory waterbirds mainly wintering at different lakes in the middle and lower Yangtze River floodplain,such as Poyang,Caizi,and Shengjin Lakes.In this study,non-invasive fecal sample collection technology and high-throughput sequencing technology of Illumina Hiseq platform were used to amplify and sequence the hypervariable region of 16 S r RNA of bacteria and ITSR1 / ITSR2 of fungi.Bioinformatics methods were used to analyze the sequencing data.The intestinal bacteria and fungi of the Hooded Cranes wintering in the three different lakes were studied to explore the effects of habitat size and protection level on intestinal microflora diversity and community composition.The results showed as fellows:1.At phylum level,Firmicutes,Proteobacteria and Actinobacteria were the dominant intestinal bacterial phyla of Hooded Cranes in the three lakes.Ascomycota,Basidiomycota and Others were the dominant intestinal fungal phyla of Hooded Cranes in the three lakes.There were significant differences in the composition and structure of bacterial and fungal community in different lakes(ANOSIM: P = 0.001).The difference of intestinal fungi community structure of the Hooded Cranes at Poyang and Shengjin Lakes was smaller than that at Shengjin and Caizi Lakes.In general,the differences of bacterial community structure in different lakes were more obvious than that of intestinal fungi.2.There were significant differences in intestinal microflora of Hooded Cranes at Poyang and Shengjin Lakes with similar habitatal conservation level but different in sizes.For the main phylum of intestinal microbes,except for Bacteroidetes and Ascomycota,there were significant differences in the distribution of main intestinal bacterial and fungal Phyla of Hooed Cranes at the two lakes(P < 0.05).The alpha diversity of intestinal bacterial and fungal community of the Hooed Cranes at Shengjin Lake(small)was significantly higher than that of Poyang Lake(large).Megamonas and Turinibacter,the core genera of geese,were both found in the intestines of the Hooed Cranes at the two lakes.The relative abundance of Megamonas and Turinibacter in the intestines of the Hooed Cranes at Shengjin Lake was higher than that of those at Poyang Lake.There were more family of Lactobacilli in the intestine of the Hooed Cranes at Poyang Lake,and the indicator bacteria of the the Hooed Cranes at Poyang Lake,Lactobacillus acidipiscis,was probiotics with a relative abundance of 50.18%.There were more potential pathogenic genera(Streptococcus and Fusarium)in the intestines of the Hooed Cranes at Shengjin Lake.In total,compared with the Hooed Cranes at Poyang Lake,the Hooed Cranes at Shengjin Lake had higher intestinal microbial alpha diversity and the more pathogen.3.There were significant differences in intestinal microflora of Hooded Cranes at Shengjin and Caizi Lakes with similar habitat size but different protection level.For the main phylum of intestinal microbes,in addition to Proteobacteria,there were significant differences in the distribution of intestinal bacterial and fungal phyla of Hooded Cranes at the two lakes(P <0.05).The alpha diversity of intestinal bacteria of the Hooded Cranes at Shengjin Lake(wellprotected habitat)was significantly higher than those at Caizi Lake.The Hooded Cranes at Shengjin Lake had more bacterial genera,such as Bacillus,Clostridium and Paenibacillus,which can metabolize cellulose and promote the degradation of non-starch polysaccharides.In addition,there were more Anaerohabdus and Ewingella in the gut of the Hooded Cranes at Caizi Lake,which might be harmful to the host and increase the risk of host disease infection,respectively.Moreover,the Hooded Cranes at Caizi Lake harbored more indicator taxa,such as Ewingella Americana,Epicoccus nigrum and Enterococcus cecorum which had a higher indicator value,had been proved to be potential intestinal pathogens.This indicated that the Hooded Cranes at Caizi Lake might be suffering from more serious invasion of pathogens and the Hooded Cranes there might be needed more attention and protection.