Establishment And Application Of A Detection Method For Tick-borne Zoonotic Anaplasma Bovis

Bovine anaplasmosis,also known as bovine border worm disease,is a globally distributed and fatal disease caused by the infection of A.bovis,which belongs to the order Rickettsiella,family Erichsiaceae and genus Anaplasmosis.It can only be parasitic in red blood cells and monocytes.It is vulnerable period is from April to October every year,and the incidence peak is from July to October.The outbreak of this disease is related to the active ticks.However,the bite of some bloodsucking insects such as: the gadfly,mosquitoes,flies and so on and contaminated injections,improper use the equipment of corner cutting and castration can also lead to the spread of the disease.The main final hosts of the disease are ruminants such as sheep,cattle,deer and elephant shrews.In recent years,with the development of science,technology and economy,there is an orderly,advanced and environmentally friendly breeding environment in the farms all over the country and even around the world.However,there are still many non-standard free-range breeding models in some poor regions and countries.In addition,due to the increased activity of ticks and pathogens caused by the greenhouse effect and global temperature rise,the infection rates of many diseases,including A.bovis,has increased.This phenomenon poses a great threat to animal health and also causes some unnecessary economic losses to people and countries.Although A.bovis has been identified as a worldwide agent through amplifing 16S sRNA(rrs),there is no literature report about the prevalence and treatment of A.bovis in Shaanxi province,and we do not know the prevalence,distribution and epidemic dynamics of A.bovis in Shaanxi province.From April 2017 to November 2019,1004 tick samples and 331 blood samples were collected from 16 locations in Xi ’an,Ankang,Hanzhong and Baoji of Shaanxi Province.Then the identification of A.bovis was carried out.Firstly,the species of ticks were identified by amplification of COI gene to determine the diversity ofthe samples.Then,rrs amplification was used to screen out the positive samples of A.bovis.Finally,a phylogenetic tree was established based on the primers designed by groEL gene to determine the gene sequences of the samples to understand their species and their relationship with the known sequences in NCBI.Among 1004 tick samples collected from Xi ’an,Ankang,Hanzhong and Baoji,55 positive ticks were detected,including 4 species in Xi ’an,34 species in Ankang,3 species in Hanzhong and 14 species in Baoji.This experiment tests the tick samples and blood samples in part region of Shaanxi province to understand the local epidemic of the disease,providing theoretical basis,prevention measurements and drug treatment of the disease for cattle and sheep farmers,so that further control the epidemiological investigation of the disease in Shaanxi province and provide reliable theory basis and the reference case.