Study On Variation And Its Determinats In Gut Microbial Communities Of Hooded Crane(Grus Monacha)Over Spatial-temporal Scales

Gastrointestinal microbiota play a vital role in maintaining organism health,through facilitating nutrient uptake,detoxification and interactions with the immune system.Numerous internal and external factors can influence gut microbial communities,including diet,seasonal fluctuations and sampling sites.However,the factors that influence the host's gut microbial composition are poorly characterized.The gastrointestinal microbiota of birds has been poorly studied,especially in wild species under natural conditions.Studies on avian gut microbiota are outnumbered ten to one by studies of mammals,and are dominated by research on domestic poultry.Unlike domestic poultry,wild birds vary widely in environmental conditions,physiology,and life-history characteristics,such as migration and mating strategy,resulting in a vast diversity in gut microbiota composition and function.In this paper,the Hooded Crane was taken as the research object,and the effects of geographical pattern,seasonal dynamics,environment and other factors on the structure and function of the host intestinal microbial complex were emphatically studied,so as to clarify the composition of the intestinal microbial community of Hooded Crane and its response to changes in environmental factors.Non-invasive techniques were used to obtain fecal samples and extract the total DNA of the host feces.The high-throughput sequencing technology(Illumina HiSeq)platform was used to perform PCR amplification and sequencing of the 16S rRNA hypervariable region,and bioinformatics analysis was performed.The following results:(1)Variation in gut microbial communities of the Hooded Crane over spatial-temporal scales.Microbes have been shown to be important symbionts that regulate the life history of the host.The composition of dominant microbial community in the intestinal tract of wintering white-head crane is similar to that of other birds,and is mainly composed of Firmicutes,Proteobacteria,Bacteroidetes and Actinobacteria.However,the intestinal microorganism has obvious changes due to the difference of time and space.At the phylum level,Firmicutes dominated in the intestinal microorganisms of the white-headed crane from Shenjin Lake,while Firmicutes and Proteobacteria were relatively abundant in Caizi Lake.In the same lake,the composition of intestinal microorganism also changed greatly with the passing of winter.In Shengjin Lake,the relative abundance of Firmicutes in the gut of Hooded Crane increased gradually with the wintering period,while the Proteobacteria decreased gradually with the wintering period.Variance partitioning analysis indicated that the physical location maybe the largest potential driver of the gut microbiota composition..(2)In addition,PICRUSt analysis revealed that the predicted metagenomes associated with carbohydrate metabolism,amino acid metabolism and energy metabolism over the entire wintering period at the two lakes.These analyses provide new insights on the gut microbial composition of the Hooded Crane,and our results serve as a foundation for future studies.(3)Males and females differ in reproductive physiology and behavior,which may manifest as different gut microbial profiles.Despite the well studied interactions between hormones and the human gut microbiota.The only study on hormone-microbiota interactions has been conducted in commercial broiler chicks.In this study,CHD gene was used to determined the sex,and gut microbes were carried out by high-throughput technique.The results showed that the gender differences of gut microbes had some effects on the alpha diversity and beta diversity of the overwintering Crane population gut microbes.However,its mechanism needs to be further studied.(4)Several studies have shown that migratory birds play an important role in the ecology,circulation and dissemination of pathogenic organisms.The second generation of high-throughput sequencing technology is used to analyze intestinal pathogenic bacterial community composition and species of wintering Hooded Crane,to clarify the intestinal pathogenic bacterial diversity and community feature.Like other vertebrates,the composition of migratory birds gut microbiota is composed of Firmicutes,Bacteroidetes,Proteobacteria.And preliminary understanding of the two kinds of migratory bird intestinal bacteria in the species,as well as human intestinal infection of microorganisms.