Fatal proventricular dilatation disease in captive native psittacines in Brazil

An outbreak of proventricular dilatation disease (PDD), a fatal inflammatory disease of psittacines (Aves: Psittaciformes), is described in native Brazilian psittacines. Twenty captive psittacines that died of suspected PDD were necropsied and 10 were submitted to histopathology, reverse transcriptase PCR (RT-PCR), and immunohistochemistry (IHC) for avian bornavirus (ABV). Examined species were one pileated parrot (Pionopsitta pileata), three vinaceous-breasted parrots (Amazona vinacea), two blue-winged macaws (Primolius maracana), one scarlet macaw (Ara macao), one chestnut-fronted macaw (Ara severa), one scaly-headed parrot (Pionus maximiliani), and one red-browed Amazon parrot (Amazona rhodocorytha). Gross examination and histopathology revealed typical PDD lesions in all birds. The presence of ABV was confirmed in four psittacines including one red-browed Amazon parrot, one blue-winged macaw, one scarlet macaw, and one chestnut-fronted macaw. In the red-browed Amazon parrot and in one blue-winged macaw, IHC demonstrated ABV antigens in the nucleus and cytoplasm of cells in various organs. This is the first description of PDD by ABV in Brazilian psittacines and indicates the necessity for adopting a strategic control plan for reducing its impact in native birds.