A broad-range survey of ticks from livestock in Northern Xinjiang: changes in tick distribution and the isolation of Borrelia burgdorferi sensu stricto.
BACKGROUND
Borreliosis is highly prevalent in Xinjiang Uygur Autonomous Region, China. However, little is known about the presence of Borrelia pathogens in tick species in this region, in addition Borrelia pathogens have not been isolated from domestic animals.


METHODS
We collected adult ticks from domestic animals at 19 sampling sites in 14 counties in northern Xinjiang from 2012 to 2014. Ticks were identified to species by morphology and were molecularly analysed by sequences of mitochondrial 16S rDNA gene; 4-8 ticks of each species at every sampling site were sequenced. 112 live adult ticks were selected for each species in every county, and were used to culture Borrelia pathogens; the genotypes were then determined by sequences of the 5S-23S rRNA intergenic spacer and the outer surface protein A (ospA) gene.


RESULTS
A total of 5257 adult ticks, belonging to four genera and seven species, were collected. Compared with three decades ago, the abundance of the five common tick species during the peak ixodid tick season has changed. Certain tick species, such as Rhipicephalus turanicus (Rh. turanicus), was found at Jimusaer, Yining, Fukang, and Chabuchaer Counties for the first time. Additionally, the sequence analyses showed that the Hyalomma asiaticum (Hy. asiaticum), Haemaphysalis punctata (Ha. punctata), and Dermacentor marginatus (D. marginatus) that were collected from different sampling sites (≥3 sites) shared identical 16S rDNA sequences respectively. For the tick species that were collected from the same county, such as Hy. asiaticum from Shihezi County and Rh. turanicus from Yining County, their 16S rDNA sequences showed genetic diversity. In addition, sixteen Borrelia isolates were found in Hy. asiaticum, Ha. punctata, D. marginatus and Rh. turanicus, which infested cattle, sheep, horse and camel in Yining, Chabuchaer, Shihezi and Shawan Counties. All of the isolates were genetically identified as B. Burgdorferi sensu stricto.


CONCLUSIONS
Warmer and wetter climate may have contributed to the altered distribution and abundance of the five most common ticks in northern Xinjiang. The genetic analyses showed that certain tick species, such as Hy. asiaticum or Rh. turanicus, exhibit genetic commonness or diversity. Additionally, this study is the first to isolate B. burgdorferi sensu stricto in Hy. asiaticum asiaticum, H. punctata, D. nuttalli and D. marginatus ticks from domestic animals. These ticks may transmit borreliosis among livestock.
School of Medicine, Shihezi University, 832003, Shihezi, Xinjiang, Peoples Republic of China.
Yuan-Zhi
YZ
Wang
School of Medicine, Shihezi University, 832003, Shihezi, Xinjiang, Peoples Republic of China.
Lu-Meng
LM
Mu
Institute of Agricultural and Rural Development, Pingdingshan University, 467000, Pingdingshan, Henan, Peoples Republic of China.
Ke
K
Zhang
School of Agriculture, Shihezi University, 832003, Shihezi, Xinjiang, Peoples Republic of China.
Mei-Hua
MH
Yang
Jinan Center for Disease Control and Prevention, 250021, Jinan, Shandong, Peoples Republic of China.
Lin
L
Zhang
School of Medicine, Shihezi University, 832003, Shihezi, Xinjiang, Peoples Republic of China.
Jing-Yun
JY
Du
School of Animal & Science, Shihezi University, 832003, Shihezi, Xinjiang, Peoples Republic of China.|Veterinary Research Institute, Xinjiang Academy of Animal Sciences, 830000, Urumqi, Xinjiang, Peoples Republic of China.
Zhi-Qiang
ZQ
Liu
School of Medicine, Shihezi University, 832003, Shihezi, Xinjiang, Peoples Republic of China.
Yong-Xiang
YX
Li
School of Animal & Science, Shihezi University, 832003, Shihezi, Xinjiang, Peoples Republic of China.
Wei-Hua
WH
Lu
School of Medicine, Shihezi University, 832003, Shihezi, Xinjiang, Peoples Republic of China. chuangfuchen666@126.com.|Institute of Agricultural and Rural Development, Pingdingshan University, 467000, Pingdingshan, Henan, Peoples Republic of China. chuangfuchen666@126.com.
Chuang-Fu
CF
Chen
School of Medicine, Shihezi University, 832003, Shihezi, Xinjiang, Peoples Republic of China.
Yan
Y
Wang
Ili Center of Animal Disease Control and Diagnosis, 835000, Ili, Xinjiang, Peoples Republic of China.
Rong-Gui
RG
Chen
Xijiang Entry - Exit Inspection and Quarantine Authority of the PRC, 830063, Urumqi, Xinjiang, Peoples Republic of China.
Jun
J
Xu
School of Medicine, Shihezi University, 832003, Shihezi, Xinjiang, Peoples Republic of China.
Li
L
Yuan
School of Medicine, Shihezi University, 832003, Shihezi, Xinjiang, Peoples Republic of China.
Wan-Jiang
WJ
Zhang
First Affiliated Hospital of School of Medicine, Shihezi University, 832008, Shihezi, Xinjiang, Peoples Republic of China.
Wei-Ze
WZ
Zuo
Genecology Research Center, University of the Sunshine Coast, Queensland, 4558, Australia.
Ren-Fu
RF
Shao
D000818:Animals; D025065:Borrelia burgdorferi / Q000302:isolation & purification*; D002681:China / Q000453:epidemiology; D058751:Livestock / Q000469:parasitology*; D010802:Phylogeny; D013045:Species Specificity; D013984:Tick Infestations / Q000453:epidemiology / Q000469:parasitology / Q000662:veterinary*; D013987:Ticks / Q000145:classification* / Q000382:microbiology*