Avian polyomavirus identified in a nestling Gouldian finch (Erythrura gouldiae) in New Zealand

Abstract

CASE HISTORY: Four 4–5-month-old nestlings and one adult in a commercial aviary of 53 Gouldian finches (Erythrura gouldiae) died over a 2-week period in July 2000.

PATHOLOGICAL FINDINGS: One nestling was necropsied and showed bronze-tinged skeletal muscles, a swollen liver with haemorrhagic margins and numerous haemorrhages on serosal surfaces. The histological lesions included multifocal hepatic necrosis and haemorrhage associated with the presence of large clear or basophilic intranuclear inclusions in hepatocytes and Kupffer cells suggestive of avian polyomavirus infection. Similar inclusion bodies were present in splenic histiocytes.

MOLECULAR BIOLOGY: DNA was subsequently extracted from archived portions of liver, spleen, gizzard, heart, lung and kidney. A broad spectrum nested PCR was used to detect polyomavirus which sequence analysis confirmed as finch polyomavirus.

DIAGNOSIS: Avian polyomavirus.

CLINICAL RELEVANCE: Avian virus infections such as polyomavirus should be suspected in cases of sudden death in nestlings, particularly in susceptible species such as psittacine and passerine birds. The archiving of tissues from unconfirmed disease outbreaks provides a valuable resource for retrospective investigations.

Keywords:

• Gouldian finch
• mortality
• hepatic necrosis
• intranuclear inclusions
• avian polyoma virus

Acknowledgments

The assistance of laboratory technicians P. Slack and P. Davey who kindly prepared the histological sections is gratefully acknowledged.