title: Clinical investigation into feed-related hypervitaminosis D in a captive flock of budgerigars (Melopsittacus undulatus): morbidity, mortalities, and pathologic lesions.
abstract: The Blank Park Zoo began suffering mortalities in the spring of 2012 within a flock of 229 captive budgerigars (Melopsittacus undulatus) housed in an interactive public-feeding aviary. Clinical signs in affected birds included weakness, posterior paresis, inability to fly, or acute death. Gross and microscopic lesions were not initially apparent in acutely affected deceased birds. Many birds had evidence of trauma, which is now hypothesized to have been related to the birds' weakness. Investigation into the cause(s) of morbidity and mortality were complicated by the opening of a new interactive enclosure. For this reason, environmental conditions and husbandry protocols were heavily scrutinized. Microscopic examination of dead budgies later in the course of the investigation revealed mineralization of soft tissues consistent with hypervitaminosis D. Pooled serum analysis of deceased birds identified elevated vitamin D3 levels. Vitamin D3 analysis was performed on the feed sticks offered by the public and the formulated maintenance diet fed to the flock. This analysis detected elevated levels of vitamin D3 that were 22.5-times the manufacturer's labeled content in the formulated diet. These findings contributed to a manufacturer recall of more than 100 formulated diets fed to a wide variety of domestic and captive wild animal species throughout the United States and internationally. This case report discusses the complexities of determining the etiology of a toxic event in a zoologic institution.
authors.forename: June E
authors.initials: JE
authors.lastname: Olds
authors.forename: Eric
authors.initials: E
authors.lastname: Burrough
authors.forename: Darin
authors.initials: D
authors.lastname: Madison
authors.forename: Steve
authors.initials: S
authors.lastname: Ensley
authors.forename: Ronald
authors.initials: R
authors.lastname: Horst
authors.forename: Bruce H
authors.initials: BH
authors.lastname: Janke
authors.forename: Kent
authors.initials: K
authors.lastname: Schwartz
authors.forename: Gregory W
authors.initials: GW
authors.lastname: Stevenson
authors.forename: Phillip
authors.initials: P
authors.lastname: Gauger
authors.forename: Vickie L
authors.initials: VL
authors.lastname: Cooper
authors.forename: Paulo
authors.initials: P
authors.lastname: Arruda
authors.forename: Tanja
authors.initials: T
authors.lastname: Opriessnig
mesh_terms: D000821:Animal Feed / Q000032:analysis*; D000822:Animal Husbandry / Q000379:methods; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D000836:Animals, Zoo; D001715:Bird Diseases / Q000139:chemically induced* / Q000401:mortality / Q000473:pathology; D002762:Cholecalciferol / Q000009:adverse effects* / Q000032:analysis / Q000097:blood; D004032:Diet / Q000662:veterinary; D062787:Drug Overdose / Q000097:blood / Q000401:mortality / Q000473:pathology / Q000662:veterinary*; D007484:Iowa / Q000453:epidemiology; D046408:Melopsittacus
chemical_list: D002762:Cholecalciferol