title: The diagnosis of proventricular dilatation disease: use of a Western blot assay to detect antibodies against avian Borna virus.
abstract: Avian Borna virus (ABV) has recently been shown to be the causal agent of proventricular dilatation disease (PDD) a lethal neurologic disease of captive psittacines and other birds. An immunoblot assay was used to detect the presence of antibodies against avian Borna virus in the serum of affected birds. A lysate from ABV-infected duck embryo fibroblasts served as a source of antigen. The assay was used to test for the presence of antibodies to ABV in 117 birds. Thirty of these birds had biopsy or necropsy-confirmed proventricular dilatation disease (PDD), while the remaining 87 birds were apparently healthy or were suffering from diseases other than PDD. Sera from 27 of the 30 PDD cases (90%) contained antibodies to ABV. Seventy-three (84%) of the apparently "healthy" birds were seronegative. Additionally, sera from seven macaws and one parrot trapped in the Peruvian Amazon were seronegative. Positive sera recognized the bornaviral nucleoprotein (N-protein). While the presence of antibodies to ABV largely corresponded with the development of clinical PDD, 14 apparently healthy normal birds possessed detectable antibodies to ABV. The existence of a carrier state was confirmed when 13 of 15 apparently healthy cockatiels were shown by PCR to have detectable ABV RNA in their feces. Western blot assays may be of significant assistance in diagnosing proventricular dilatation disease. Many apparently healthy birds may however be seronegative while, at the same time, shedding ABV in their feces.
authors.affiliation: The Schubot Exotic Bird Health Center, Department of Veterinary Pathobiology, Texas A&M University, College Station, TX 77840, USA.
authors.forename: Itamar
authors.initials: I
authors.lastname: Villanueva
authors.forename: Patricia
authors.initials: P
authors.lastname: Gray
authors.forename: Negin
authors.initials: N
authors.lastname: Mirhosseini
authors.forename: Susan
authors.initials: S
authors.lastname: Payne
authors.forename: Sharman
authors.initials: S
authors.lastname: Hoppes
authors.forename: Kirsi S
authors.initials: KS
authors.lastname: Honkavuori
authors.forename: Thomas
authors.initials: T
authors.lastname: Briese
authors.forename: Debra
authors.initials: D
authors.lastname: Turner
authors.forename: Ian
authors.initials: I
authors.lastname: Tizard
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000097:blood*; D001715:Bird Diseases / Q000097:blood / Q000276:immunology / Q000821:virology; D015153:Blotting, Western / Q000662:veterinary*; D001890:Borna Disease / Q000097:blood / Q000175:diagnosis*; D001891:Borna disease virus / Q000276:immunology*; D011563:Psittaciformes; D012680:Sensitivity and Specificity; D012698:Serologic Tests / Q000662:veterinary
chemical_list: D000914:Antibodies, Viral