Unusual Pathologic Brain Changes Associated with Zinc Toxicosis in a Blue-Fronted Amazon Parrot (Amazona aestiva)

Authors

Andrea N. Savarese, Department of Veterinary Clinical Sciences, Louisiana State University, College of Veterinary Medicine, Skip Bertman Drive, Baton Rouge, LA 70803.
Kyra J. Berg, William T. Pritchard Veterinary Medical Teaching Hospital, School of Veterinary Medicine, University of California Davis, One Shields Avenue, Davis, CA 95616.
Daniel B. Paulsen, Department of Pathobiological Sciences, Louisiana State University, College of Veterinary Medicine, Skip Bertman Drive, Baton Rouge, LA 70803.
Emi Sasaki, Department of Pathobiological Sciences, Louisiana State University, College of Veterinary Medicine, Skip Bertman Drive, Baton Rouge, LA 70803.
Mathew Stewart, Department of Veterinary Clinical Sciences, Louisiana State University, College of Veterinary Medicine, Skip Bertman Drive, Baton Rouge, LA 70803.
Lorrie E. Gaschen, Department of Veterinary Clinical Sciences, Louisiana State University, College of Veterinary Medicine, Skip Bertman Drive, Baton Rouge, LA 70803.
Peter L. Jowett, Department of Pathobiological Sciences, Louisiana State University, College of Veterinary Medicine, Skip Bertman Drive, Baton Rouge, LA 70803.
Thomas N. Tully, Department of Veterinary Clinical Sciences, Louisiana State University, College of Veterinary Medicine, Skip Bertman Drive, Baton Rouge, LA 70803.

Document Type

Article

Publication Date

12-1-2020

Abstract

An adult blue-fronted Amazon parrot (Amazona aestiva) was presented for a 6-wk history of ataxia and weight loss. Complete blood count, plasma chemistry panel, bile acids, and radiographic imaging were considered normal or unremarkable. The patient was hospitalized and supported with subcutaneous fluids, vitamin B complex, meloxicam, enrofloxacin, gavage feeding, and fenbendazole. While hospitalized, the ataxia significantly improved, and the bird began eating on its own and gaining weight. The bird was discharged from the hospital and prescribed enrofloxacin, meloxicam, and fenbendazole to be administered by the owner with recommendations for routine follow-up care. Medications were discontinued before emergent representation; at the time of reevaluation, the patient's condition had deteriorated severely. Given the poor prognosis, the owners elected for euthanasia. No gross abnormalities were noted on postmortem examination. Liver tissue zinc levels measured 125 ppm; normal limit is less than or equal to 25 ppm. Histopathologic changes to the brain were consistent with severe zinc toxicosis demonstrated by vasculopathy of the cerebral arteries and arterioles with multifocal areas of hemorrhage and astrocyte swelling. These findings have been reported in humans and other mammals but not birds. Although the source of this bird's heavy metal exposure is unknown, the high tissue zinc concentrations imply chronic exposure. This case presentation and unusual pathologic findings will be beneficial to the further understanding of avian zinc toxicosis.

Publication Source (Journal or Book title)

Avian diseases

First Page

478

Last Page

481

Recommended Citation

Savarese, A. N., Berg, K. J., Paulsen, D. B., Sasaki, E., Stewart, M., Gaschen, L. E., Jowett, P. L., & Tully, T. N. (2020). Unusual Pathologic Brain Changes Associated with Zinc Toxicosis in a Blue-Fronted Amazon Parrot (Amazona aestiva). Avian diseases, 64 (4), 478-481. https://doi.org/10.1637/0005-2086-64.4.478