Peripheral neuritis in psittacine birds with proventricular dilatation disease

Necropsies were performed on 14 psittacine birds of various species suspect ed to have proventricular dilatation disease (PDD). Eight of the birds exhi bited neurological signs ( seizures, ataxia, tremors and uncoordinated move ments) and digestive tract signs (crop stasis, regurgitation, inappetance a nd presence of undigested food in the faeces). At necropsy, the birds had p ectoral muscle atrophy, proventricular and ventricular distention, thinning of the gizzard wall, and duodenal dilation. In addition, five birds had a transparent fluid (0.2 to 1.0 ml) in the subarachnoidal space of the brain, and one bird had dilatation of the right ventricle of the heart. The histo logical lesions differed from earlier reports of PDD in that peripheral (sc iatic, brachial and vagal) neuritis was seen in addition to myenteric gangl ioneuritis, myocarditis, adrenalitis, myelitis and encephalitis.