title: Avian bornavirus genotype 4 recovered from naturally infected psittacine birds with proventricular dilatation disease in South Africa.
abstract: The occurrence of proventricular dilatation disease caused by avian bornavirus (ABV) in  captive psittacine birds has long been suspected in South Africa. This report documents the first  detection by polymerase chain reaction and gene sequence analyses of ABV from three clinical  cases of proventricular dilatation disease (PDD) in captive bred blue and gold macaws (Araara  rauna) resident in this country. Lymphoplasmacytic encephalitis, gastrointestinal myenteric  gangioneuritis and leiomyositis were the most prominent histopathological changes and ABV  genotype 4 was detected in tissues from all three birds. Immunohistochemical stains for ABV  antigen revealed positive labelling of neurons and glial cells of the brain, myenteric ganglia  and nerve fibres as well as smooth muscle cells of the gastrointestinal tract of all three birds.  In one bird, positive labelling of the peripheral nerves was observed. The identical sequence  of the analaysed genome fragment of all three samples, history that all of these birds had  originated from the same breeding facility, and young age at presentation raise the question  of possible vertical transmission.
authors: Vetdiagnostix - Veterinary Pathology Services, Cascades, South Africa. vetdiagnostix@futurenet.co.za
authors: Robert D
authors: RD
authors: Last
authors: Herbert
authors: H
authors: Weissenböck
authors: Nora
authors: N
authors: Nedorost
authors: H L
authors: HL
authors: Shivaprasad
mesh_terms: D000818:Animals; D001715:Bird Diseases / Q000453:epidemiology / Q000821:virology*; D028981:Bornaviridae / Q000145:classification / Q000235:genetics*; D004108:Dilatation, Pathologic / Q000662:veterinary; D017809:Fatal Outcome; D018701:Mononegavirales Infections / Q000453:epidemiology / Q000662:veterinary* / Q000821:virology; D010311:Parrots; D016133:Polymerase Chain Reaction / Q000662:veterinary; D011531:Proventriculus / Q000473:pathology*; D013019:South Africa / Q000453:epidemiology; D013272:Stomach Diseases / Q000453:epidemiology / Q000662:veterinary* / Q000821:virology