Comparative analysis of microbial communities in different growth stages of .

Ticks were identified as arthropods that are pathogenic vectors. is one of the dominant tick species in Inner Mongolia, and it carries and transmits a wide range of pathogenic microorganisms. However, at present, only the detection of adult ticks and different developmental stages carrying one specific pathogen, or the next-generation sequencing of adult ticks were available. In this study, we investigated the microbial community structures of in different growth stages under laboratory artificial feeding conditions. Total DNA was extracted from seven growth stages (female adult ticks, eggs, larval ticks, engorged larval ticks, nymphal ticks, engorged nymphal ticks, and second-generation adult ticks) obtained from laboratory artificial feeding of engorged female ticks in Inner Mongolia. Then, the 16S rDNA V3-V4 hypervariable region was amplified to construct an Illumina PE250 library. Finally, 16S rRNA sequencing was performed on Illumina Novaseq 6000 platform. The sequencing data were analyzed using molecular biology software and platforms. The Illumina PE250 sequencing results showed that the egg stage had the highest diversity and number of species (28.74%, 98/341), while the engorged nymph stage had the lowest diversity and number of species (9.72%, 21/216). A total of 387 genera of 22 phyla were annotated in , with 9 phyla and 57 genera found throughout all 7 growth stages. The dominant phylum was Proteobacteria; the dominant genera were and ; and the genera with the highest relative abundance in the 7 growth stages were , and , respectively. Among the 23 exact species annotated, exhibits pathogeny that poses a serious threat to humans and animals. In this study, the microbial community composition at different growth stages of was comprehensively analyzed for the first time.