title: Seroprevalence of turkey coronavirus in North American turkeys determined by a newly developed enzyme-linked immunosorbent assay based on recombinant antigen.
abstract: Turkey coronavirus (TCoV) causes diarrhea in young turkey poults, but little is known about its prevalence in the field. To address this, the complete nucleocapsid gene was cloned and expressed in Escherichia coli. Expressed nucleocapsid gene produced two distinct proteins (52 and 43 kDa); their specificity was confirmed by Western blotting using two different monoclonal antibodies. Recombinant N protein was purified and used as an antigen to develop an enzyme-linked immunosorbent assay (ELISA) for the serological detection of TCoV that was then validated using experimentally derived turkey serum. The N-based ELISA showed (97%) sensitivity and (93%) specificity for TCoV, which was significantly higher than an infectious bronchitis coronavirus-based commercial test for TCoV. To assess the utility of this recombinant ELISA, 360 serum samples from turkey farms in Ontario, Canada, and 81 serum samples from farms in Arkansas were tested for TCoV-specific antibodies. A high seroprevalence of TCoV was found in turkeys from the Ontario farms with 73.9% of breeders and 60.0% of meat turkeys testing seropositive using the N-based ELISA. Similarly, a high field prevalence was found in the turkeys from Arkansas, for which 64.2% of the serum samples tested seropositive.
authors.affiliation: Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
authors.forename: Maged H
authors.initials: MH
authors.lastname: Gomaa
authors.forename: Dongwan
authors.initials: D
authors.lastname: Yoo
authors.forename: Davor
authors.initials: D
authors.lastname: Ojkic
authors.forename: John R
authors.initials: JR
authors.lastname: Barta
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000097:blood*; D004752:Coronavirus, Turkey / Q000276:immunology*; D003429:Cross Reactions / Q000276:immunology; D004753:Enteritis, Transmissible, of Turkeys / Q000453:epidemiology* / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D009656:North America / Q000453:epidemiology; D019590:Nucleocapsid Proteins / Q000276:immunology*; D015995:Prevalence; D011993:Recombinant Fusion Proteins / Q000276:immunology; D012680:Sensitivity and Specificity; D016036:Seroepidemiologic Studies; D014422:Turkeys / Q000276:immunology / Q000821:virology
chemical_list: D000914:Antibodies, Viral; D019590:Nucleocapsid Proteins; D011993:Recombinant Fusion Proteins