The gut bacteria across life stages in the synanthropic fly Chrysomya megacephala

Abstract

Background: Gut bacteria are closely associated with host. Chrysomya megacephala, as a vector and resource insect, can transmit various pathogenic bacteria and consume manure to produce biofertilizer and larva biomass. However, the gut bacteria composition and abundance of C. megacephala remain unclear. Results: Illumina MiSeq platform was used to compare composition of gut bacterial community in eggs, 1-day-old larvae, 5-day-old larvae, pupae, adult females and males by sequencing with variation in V4 region of 16S ribosomal DNA gene. In total, 928 operational taxonomic units (OTUs) were obtained. These OTUs were annotated into 19 phyla, 42 classes, 77 orders, 153 families and 289 genera. More than 0.5% abundance of 32 OTU core genera were found across all life stages. At class level, Alphaproteobacteria, Bacilli, Bacteroidia, Betaproteobacteria, Flavobacteriia and Gammaproteobacteria were the most abundant in C. megacephala. Eight species were identified to have significantly different abundance between 1-d-larvae and 5-day-larvae and took 28.95% of shared species between these two groups. Sex-specific bacterial species were identified that Faecalibacterium prausnitzii was merely present in females, while Rhodococcus fascians was merely present in males. Conclusion: Gut bacteria of C. megacephala varied across life stages. The composition and community structure of the bacterial community differed from young larvae to mature larvae, while that were similar in adult females and males. These data will provide an overall view of bacterial community across life stages in C. megacephala with attention on manure associated and pathogenic bacteria.