title: Seroprevalence and risk factors of Chlamydia abortus infection in free-ranging white yaks in China.
abstract: BACKGROUND
  Chlamydia is gram-negative obligate bacteria which causes a wide variety of diseases in humans and animals. To date, there are a few reports about the seroprevalence of Chlamydia and the risk factors associated with Chlamydia infection in yaks in the world. In this study, 974 blood samples were collected from white yaks (Bos grunniens) in Tianzhu Tibetan Autonomous County, Gansu province, northwest China from June 2013 to April 2014.
  
  
  RESULTS
  Antibodies against Chlamydia abortus were examined by the indirect hemagglutination (IHA) test, and 158 of 974 (16.22%) white yaks were seropositive for C. abortus antibodies at the cut-off of 1:16. The risk factors associated with seroprevalence were evaluated by a multivariate logistic regression analysis. Region, gender and age of white yak were left out of the final model, due to its insignificance in the logistic regression analysis (P > 0.05). However, season was considered as a major risk factor associated with C. abortus infection in white yaks.
  
  
  CONCLUSIONS
  To our knowledge, this is the first survey of C. abortus seroprevalence in white yaks in China, which extends the host range for C. abortus and has important implications for public health and the local Tibetan economy.
authors.affiliation: College of Animal Science and Technology, Jilin Agricultural University, Changchun, Jilin Province, 130118, PR China. qinsiyuan0303@126.com.|State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, 730046, PR China. qinsiyuan0303@126.com.
authors.forename: Si-Yuan
authors.initials: SY
authors.lastname: Qin
authors.affiliation: State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, 730046, PR China. siyang.huang@hotmail.com.
authors.forename: Si-Yang
authors.initials: SY
authors.lastname: Huang
authors.affiliation: State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, 730046, PR China. 106208120@qq.com.|College of Veterinary Medicine, Hunan Agricultural University, Changsha, Hunan Province, 410128, PR China. 106208120@qq.com.
authors.forename: Ming-Yang
authors.initials: MY
authors.lastname: Yin
authors.affiliation: State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, 730046, PR China. ahndtan_qidong@126.com.|College of Animal Science and Technology, Anhui Agricultural University, Hefei, Anhui Province, 230000, PR China. ahndtan_qidong@126.com.
authors.forename: Qi-Dong
authors.initials: QD
authors.lastname: Tan
authors.affiliation: State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, 730046, PR China. lgx950240@163.com.
authors.forename: Guang-Xue
authors.initials: GX
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, 730046, PR China. donghui822002@163.com.
authors.forename: Dong-Hui
authors.initials: DH
authors.lastname: Zhou
authors.affiliation: College of Animal Science and Technology, Jilin Agricultural University, Changchun, Jilin Province, 130118, PR China. xingquanzhu1@hotmail.com.|State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, 730046, PR China. xingquanzhu1@hotmail.com.
authors.forename: Xing-Quan
authors.initials: XQ
authors.lastname: Zhu
authors.affiliation: State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, 730046, PR China. zhoujizhang@caas.cn.
authors.forename: Ji-Zhang
authors.initials: JZ
authors.lastname: Zhou
authors.affiliation: College of Animal Science and Technology, Jilin Agricultural University, Changchun, Jilin Province, 130118, PR China. qianaidong0115@163.com.
authors.forename: Ai-Dong
authors.initials: AD
authors.lastname: Qian
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D002417:Cattle; D002689:Chlamydia / Q000302:isolation & purification*; D002690:Chlamydia Infections / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D005260:Female; D008297:Male; D012307:Risk Factors; D016036:Seroepidemiologic Studies
chemical_list: D000907:Antibodies, Bacterial