title: Pathogenesis comparison between the United States porcine epidemic diarrhoea virus prototype and S-INDEL-variant strains in conventional neonatal piglets.
abstract: At least two genetically different porcine epidemic diarrhoea virus (PEDV) strains have been identified in the USA: US PEDV prototype and S-INDEL-variant strains. The objective of this study was to compare the pathogenicity differences of the US PEDV prototype and S-INDEL-variant strains in conventional neonatal piglets under experimental infections. Fifty PEDV-negative 5-day-old pigs were divided into five groups of ten pigs each and were inoculated orogastrically with three US PEDV prototype isolates (IN19338/2013, NC35140/2013 and NC49469/2013), an S-INDEL-variant isolate (IL20697/2014), and virus-negative culture medium, respectively, with virus titres of 104 TCID50 ml- 1, 10 ml per pig. All three PEDV prototype isolates tested in this study, regardless of their phylogenetic clades, had similar pathogenicity and caused severe enteric disease in 5-day-old pigs as evidenced by clinical signs, faecal virus shedding, and gross and histopathological lesions. Compared with pigs inoculated with the three US PEDV prototype isolates, pigs inoculated with the S-INDEL-variant isolate had significantly diminished clinical signs, virus shedding in faeces, gross lesions in small intestines, caeca and colons, histopathological lesions in small intestines, and immunohistochemistry staining in ileum. However, the US PEDV prototype and the S-INDEL-variant strains induced similar viraemia levels in inoculated pigs. Whole genome sequences of the PEDV prototype and S-INDEL-variant strains were determined, but the molecular basis of virulence differences between these PEDV strains remains to be elucidated using a reverse genetics approach.
authors: Department of Veterinary Diagnostic and Production Animal Medicine, Iowa State University, Ames, IA, USA.
authors: Qi
authors: Q
authors: Chen
authors: Department of Veterinary Diagnostic and Production Animal Medicine, Iowa State University, Ames, IA, USA.
authors: Phillip C
authors: PC
authors: Gauger
authors: Department of Veterinary Diagnostic and Production Animal Medicine, Iowa State University, Ames, IA, USA.
authors: Molly R
authors: MR
authors: Stafne
authors: Department of Veterinary Diagnostic and Production Animal Medicine, Iowa State University, Ames, IA, USA.
authors: Joseph T
authors: JT
authors: Thomas
authors: Department of Veterinary Diagnostic and Production Animal Medicine, Iowa State University, Ames, IA, USA.
authors: Darin M
authors: DM
authors: Madson
authors: Department of Veterinary Diagnostic and Production Animal Medicine, Iowa State University, Ames, IA, USA.
authors: Haiyan
authors: H
authors: Huang
authors: Department of Veterinary Diagnostic and Production Animal Medicine, Iowa State University, Ames, IA, USA.
authors: Ying
authors: Y
authors: Zheng
authors: Department of Veterinary Diagnostic and Production Animal Medicine, Iowa State University, Ames, IA, USA.
authors: Ganwu
authors: G
authors: Li
authors: Department of Veterinary Diagnostic and Production Animal Medicine, Iowa State University, Ames, IA, USA.
authors: Jianqiang
authors: J
authors: Zhang
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D018352:Coronavirus Infections / Q000453:epidemiology / Q000662:veterinary* / Q000821:virology; D014644:Genetic Variation; D053485:Porcine epidemic diarrhea virus / Q000235:genetics / Q000472:pathogenicity*; D012367:RNA, Viral; D013552:Swine; D013553:Swine Diseases / Q000453:epidemiology / Q000821:virology*; D014481:United States / Q000453:epidemiology; D014774:Virulence; D017201:Virus Shedding
chemical_list: D012367:RNA, Viral