The Composition Of Gut Microbiota Community Structure And Influencing Factors Of Jankowski’s Bunting(Emberiza Jankowskii)in Breeding Season Under Grassland Habitat Degradation And Fragmentation

Habitat degradation and fragmentation are the most major threats to species diversity worldwide.Grassland habitat fragmentation and degradation were not equivalent in their effects on different species,with the most pronounced effects on bird retention populations with narrow distribution areas and small numbers.Jankowski’s Bunting(Emberiza jankowskii)is a typical prairie bird species with a narrow and sharply shrunken distribution area,low reproductive success and a continuous population decline,and its population status has received great attention in China and abroad.2010,with the International Union for Conservation of Nature(IUCN)from vulnerable(VU)to endangered(EN),and listed it in List of key protected wild animals in China grade Ⅰ in February 2021.The study of gut microbiology in wild animals is great importance in conservation biology.The gut microbiota is an essential part of vertebrate maintenance of health,and its community structure composition is influenced by dietary,environmental as well as genetic factors.Birds have attracted increasing attention for the study of their gut microbiota because of their wide distribution and high food differences.With the development of conservation biology,the study of intestinal microbes in endangered birds is particularly important in preserving biodiversity.The object of this study was the endangered wild bird Jankowski’s Bunting(Emberiza jankowskii)under habitat degradation and fragmentation,and describe the reproductive ecology and genetic diversity.With the aid of 16 S r RNA high-throughput sequencing technology to investigate the effect of dietary and the microenvironment in the development of the gut microbiota of Jankowski’s Bunting adults and nestlings,and the influence of gut microbial community structure on their body condition.We analyzed gut microbiology community structure and compositional differences between relatives Meadow Bunting which unaffected by habitat habitat degradation and fragmentation and Jankowski’s Bunting.To investigate the effect of gut microbiology community structure and composition of Jankowski’s Bunting effect by habitat degradation and fragmentation.Analyze the composition differences of nestlings gut microbiota between Jankowski’s Bunting and its parasitic species of Cuckoo with different life histories,and to explore the effects of habitat degradation and fragmentation on the gut microbiota of the Jankowski’s Bunting and Cuckoo nestlings.Through the above analysis,elucidation of the main factors affecting the gut microbial community on Jankowski’s Bunting in breeding season under habitat degradation and fragmentation.1.The main reasons for reproductive failure of Jankowski’s Bunting are predation by natural enemies,and genetic diversity of Jankowski’s Bunting is higher than other endangered species on habitat degradation and fragmentation.It was suggested that habitat fragmentation and degradation had no significant effect on the genetic diversity of Jankowski’s Bunting.2.The community structure of the Jankowski’s Bunting’s gut microbiota during breeding season was dominated by the phyla Proteobacteria,Firmicutes,Bacteroidetes,as well as Actinobacteria.There was no significant difference in gut microbial richness between nestlings and adults(P>0.05),however,it was higher than adults,and diversity was significantly lower than adults(P<0.05).With increasing age,the genera Delftia,Streptococcus,Pseudomonas tended to decrease in abundance,while the genera Rubrobacter,Pseudonocardia,Bosea,Arthrobacter and Methylobacterium increased with age.3.The effect of dietary OTU richness on the gut microbial OTU richness of Jankowski’s Bunting’s adults and nestlings was significant(P < 0.05),but the nest microenvironment as well as food and nest microenvironment interaction had no significant effect on the gut microbial richness of Jankowski’s Bunting’s adults and nestlings(P> 0.05).At age 6 days,the higher the gut microbial richness of the nestlings,the better for their body condition.At age 9 days,the higher of the nestlings gut microbial diversity,the better for their body condition.With the increase of the age of nestlings,the abundance of nestlings’ gut microbiota was decrease and the diversity was increase.4.There were no significant differences in gut microbial community diversity and abundance between the adults of Jankowski’s Bunting and Meadow Bunting.But the abundance of Jankowski’s Bunting nestlings’ gut microbiota was significant higher than Meadow Bunting,and the diversity was no significant.Lef Se revealed the higher abundances of Sphingomonas,Sediminibacterium,Herminiimonas,Pseudomonas than Meadow Bunting,and Klebsiella,Lactobacillus and Pantoea was lower than Meadow Bunting.Compared with Meadow Bunting,the more gut microbiota’s function of Jankowski’s Bunting was degrading the environmental pollutants and reducing the toxicity.5.There are significant differences in the gut microbial community composition between Jankowski’s Bunting nestlings and Cuckoo nestlings.Jankowski’s Bunting nestlings gut microbial are dominated by Proteobacteria,whereas the Cuckoo are dominated by Firmicutes.The Cuckoo gut microbial diversity was significantly higher(P<0.05)than Jankowski’s Bunting and the abundance was no significant differences.The different life history maybe the main reason for the difference of gut microbiota between the Cuckoo and Jankowski’s Bunting.Lef Se revealed the higher abundances of Catenulispora,Bordetella,Desulfotignum and Bartonella than Jankowski’s Bunting nestlings,and the abundances of Sphingomonas was lower than Jankowski’s Bunting nestlings.Gut microbiota with the function of degrading organic pollutants were detected in both birds,indicating that habitat degradation and fragmentation affected the composition of gut microbiota in the two birds.