title: Pathogenesis of natural and experimental Pseudorabies virus infections in dogs.
abstract: BACKGROUND
  Since late 2011, cases of suspected canine pseudorabies have increased in north China with the outbreak of swine pseudorabies in the same area, but the pathogenesis of canine Pseudorabies virus (PRV) infections in China is poorly understood. In this study, we investigated the pathogenesis of canine pseudorabies.
  
  
  METHODS
  The pathological changes in 13 dogs that died of natural PRV infections (confirmed by pathogen detection) during 2011-2013 in Beijing were evaluated. An experimental study was also conducted in which healthy adult beagle dogs were administered PRV isolate BJ-YT by subcutaneous injection. The dog tissues were subjected to gross and microscopic examinations and immunohistochemical analysis and the dogs' serum cardiac troponin-I (cTn-I) was measured.
  
  
  RESULTS
  Systemic hemorrhage and/or congestion were the most marked pathological changes in both the naturally and experimentally PRV-infected dogs. Macroscopically, the major lesions consisted of petechiae and ecchymoses in both the endocardium and epicardium, thrombi in the mitral valves, hemorrhage in the lungs and thymus, and incomplete contraction of the spleen. Microscopically, the major histopathological findings were systemic hemorrhage and congestion, nonsuppurative ganglioneuritis (in the experimentally infected dogs, unexamined in the naturally PRV-infected dogs), brainstem encephalitis (in the naturally infected dogs), necrosis or exudation in the myocardium, and lymphoid depletion in many lymphoid organs and tissues. Viral antigens were only detected in the brainstems and peripheral ganglia of the infected dogs. Serum cTn-I was significantly higher in the experimentally PRV-infected dogs with myocardial lesions than in the dogs without myocardial lesions.
  
  
  CONCLUSIONS
  Based on these results, we conclude that virally induced systemic hemorrhage, peripheral nervous system pathology, and/or cardiac injury can individually or collectively cause death in PRV-infected dogs. The respiratory signs of the disease are attributed to cardiogenic lesions.
authors.affiliation: College of Veterinary Medicine, China Agricultural University, 100193, Beijing, P R China. zltcau@sina.cn.
authors.forename: Letian
authors.initials: L
authors.lastname: Zhang
authors.affiliation: College of Veterinary Medicine, China Agricultural University, 100193, Beijing, P R China. zhongc@cau.edu.cn.
authors.forename: Cheng
authors.initials: C
authors.lastname: Zhong
authors.affiliation: College of Veterinary Medicine, China Agricultural University, 100193, Beijing, P R China. 714955069@qq.com.
authors.forename: Jushi
authors.initials: J
authors.lastname: Wang
authors.affiliation: College of Veterinary Medicine, China Agricultural University, 100193, Beijing, P R China. alloblue@aliyun.com.
authors.forename: Zijie
authors.initials: Z
authors.lastname: Lu
authors.affiliation: College of Veterinary Medicine, China Agricultural University, 100193, Beijing, P R China. liul@cahg.com.cn.|China Animal Husbandry Group, 100070, Beijing, P R China. liul@cahg.com.cn.
authors.forename: Lei
authors.initials: L
authors.lastname: Liu
authors.affiliation: College of Veterinary Medicine, China Agricultural University, 100193, Beijing, P R China. 184837082@qq.com.
authors.forename: Wanlian
authors.initials: W
authors.lastname: Yang
authors.affiliation: College of Veterinary Medicine, China Agricultural University, 100193, Beijing, P R China. luyanli@cau.edu.cn.
authors.forename: Yanli
authors.initials: Y
authors.lastname: Lyu
mesh_terms: D000818:Animals; D002681:China; D004283:Dog Diseases / Q000473:pathology / Q000821:virology*; D004285:Dogs; D005260:Female; D011558:Herpesvirus 1, Suid / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D008099:Liver / Q000473:pathology / Q000821:virology; D008168:Lung / Q000473:pathology / Q000821:virology; D008297:Male; D011557:Pseudorabies / Q000473:pathology / Q000821:virology*; D013950:Thymus Gland / Q000473:pathology / Q000821:virology