Suspected Zinc Toxicosis as a Cause of Sudden Death in Orange -Bellied Parrots (Neophema chrysogaster)

A syndrome of sudden death in captive orange-bellied parrots (Neophema chrysogaster) was associated with zinc toxicosis. A total of 77 birds was examined, with most being found dead in good flesh with no histologic lesions. Affected birds had a mean zinc level of 154.3 μg/g in the kidneys, 289.8 μg/g in the liver, and 723.6 μg/g in the pancreas. These values were compared with a mean zinc level of 65.3 μg/g in kidneys of unaffected birds. Additionally, the fertility rate in this population of captive parrots was 54% in 1995-96, 59% in 1996-97, and 66% in 1997-98. After all galvanized wire was replaced with nylon mesh before the 1998-99 breeding season, the fertility rate increased to 86%. Ingestion of zinc can affect the central nervous system, and birds with neurologic signs may have died as a result of colliding with walls or structures in the aviaries. The absence of histologic lesions usually associated with zinc toxicosis in affected birds may have been related to acute head trauma as the cause of death. © 2000 by the Association of Avian Veterinarians.