Artificial Breeding And Microbial Community Composition Of Dermacentor Nuttalli In Inner Mongolia

Dermacentor nuttalli belongs to the Ixodinae,Dermacentor.As the predominant tick species in Inner Mongolia,transmission of viruses,spirochete,rickettsiella,bacteria or protozoa when biting or sucking blood has the risk of transmitting diseases from wild animals or domestic animals to humans.In order to provide sufficient and effective experimental materials for the further study of Dermacentor nuttalli,ticks from Hulunbuir region of Inner Mongolia were selected as research objects and identified by morphological and molecular biology methods.The life history of Dermacentor nuttalli was studied in laboratory artificially by using Kunming mice as the only blood feeding animal,and the laboratory population was established.On this basis,the microbial community composition of Dermacentor nuttalli was studied based on 16 S r DNA Illumina PE250 high-throughput sequencing technology,and the microbial community and diversity carried by Dermacentor nuttalli at different growth stages were understood.To provide scientific basis for prevention and treatment of Dermacentor nuttalli and related tick-borne diseases.The results showed that tick species collected from sheep in Hulunbuir region of Inner Mongolia were confirmed as Dermacentor nuttalli by morphological and molecular biological identification.The spawning period of sated female ticks was 13～18 days,with an average daily number of 219 eggs and a total number of 2680～4050 eggs.Tick eggs hatched into juvenile ticks after 25～29 days,and the hatching rate reached 93.33%.The feeding period of juvenile ticks was 4～6 days,and the ecdysis period was 4～15 days,and the ecdysis rate was 80.89%.If the vampiric period was 4～8 days and the ecdysis period was 12～21 days,the ecdysis rate reached 68.10%.It took 72 d to 114d(90.66 d on average)from the spawning stage to the adult stage of the next generation.The results of high-throughput sequencing were mainly annotated as proteobacteria,Firmicutes,Bacteroidetes and actinobacteria.The relative abundance of proteobacteria in Dermacentor nuttalli at different growth stages was the highest.At the genus level,Arsenophonus and Rickettsiae were dominant in all growth stages of Dermacentor nuttalli,with slightly different dominant genera in different stages.Pseudomonas and Rickettsiae were the dominant bacteria in the first generation of female adult ticks,Paenalcaligenes were the dominant bacteria in eggs,Arsenophonus and Rickettsiae were the dominant bacteria in Larva,full blood larva and full blood nymph.Pseudomonas and Brevundimonas were the dominant bacteria in nymph.Rickettsiae and Alcaligenes were the dominant species in the next generation ticks.Eggs had the most abundant microbial diversity,while full blood nymph had less microbial species.Rickettsiae is dominant in different growth stages of Dermacentor nuttalli and may be endosymbiont of Dermacentor nuttalli.This study is the first time to breed and breed Dermacentor nuttalli in Inner Mongolia and observe their life history.It was also the first time to comprehensively study the microbial community carried by Dermacentor nuttalli at different growth stages based on high-throughput sequencing technology.It laid a foundation for further study and prevention of Dermacentor nuttalli and its tick-borne diseases.