Monoclonal hyperglobulinemia in lymphosarcoma in a cockatiel (Nymphicus hollandicus) and a blue and gold macaw (Ara ararauna).

A 15-yr-old cockatiel (Nymphicus hollandicus) presented with decreased activity and appetite. A presumptive diagnosis of lymphoproliferative disease was made because of a monoclonal band observed on plasma protein electrophoresis. The owner declined further diagnostics or treatment, and the bird died 2 yr later. In a second case, a 4-yr-old blue and gold macaw (Ara ararauna) presented with lethargy and anorexia. Despite supportive treatment, the bird died 7 days later. Blood studies also demonstrated a monoclonal band on plasma protein electrophoresis. The histologic review of tissues from both birds found extensive neoplastic lymphoplasmocytic cells in the liver and supported a diagnosis of lymphosarcoma.