Identification Of Tick Species And Detection Of Tick-borne Rickettsia In Sheep In Some Areas,Southern Xinjiang

In order to grasp the distribution of tick species and the status of Rickettsia and Anaplasma carried by ticks in sheep in parts of southern Xinjiang.In 2018-2019,parasitic ticks were collected from Awati,Wushi,Shaya,Kuche,Xinhe,Atush,Shache,Shufu,Zepu,Yecheng,Kashi,Pishan,the 8th group of Alar city,the 10 th group of Alar city,the 13 th group of Alar city and the 11 th group of Alar city.The collected ticks were identified by morphology,molecular biology by mitochondrial 16 S rDNA gene and phylogenetic analysis.Then PCR was used to amplify the Rickettsia gene fragment of all tick species,including Rickettsia outer membrane protein A,B gene,gltA citric acid synthetase gene,16 S rRNA ribosome gene,17 kDa protein antigen,and Anaplasma 16 S rRNA ribosome gene sequence the positive samples and analyze the sequence through Blast.DNA Star software and mega 6.0 software were used to construct the phylogenetic tree and analyze the species genetic relationship of Rickettsia and Anaplasma.The results showed that:(1)A total of 2614 parasitic ticks were collected from 17 sampling sites in southern Xinjiang,including 4 genera and 5 species,Ixodes include Rhipicephalus turanicus,Dermacentor marginatus,Dermacentor niveus,Hyalomma asiaticum and Argas include Argas Lahorensis;(2)In 488 tick DNA samples from 17 sampling sites in southern Xinjiang,145 Rickettsia positive samples and 47 Anaplasma positive samples were detected,with an average infection rate of 29.7% and 9.6%,respectively;(3)There were four kinds of Rickettsia infection in part of Southern Xinjiang,Rickettsia raoultii,Rickettsia conorii,Rickettsia massiliae and Candidatus Rickettsia barbariae,The Rickettsia carrying rate of each sampling point was between 0%-90%,and that of each tick was 17.7%-100%;(4)There are two kinds of Anaplasma infection in some areas,southern Xinjiang,Anaplasma phagocytophohilum and Anaplasma ovis,The carrying rate of Anaplasma in each sampling site is between 0%-72.2%,and that of ticks is 0%-20.6%.In this study Rhipicephalus turanicus was the dominant tick species,the development of tick species was relatively conservative in genetic evolutionn in part of Southern Xinjiang;The results of pathogen investigation showed that there was a high rate of Rickettsia in ticks;Rickettsia raoultii was first detected in Dermacentor niveus parasitized on sheep in southern Xinjiang and Anaplasma phagocytophohilum was detected in Argas Lahorensis in sheep in southern Xinjiang.This experiment complemented the distribution of tick species in this area,and provided an important basis for the study and control of tick borne Rickettsia in southern Xinjiang.