Papilloma - Fish

Introduction

Papillomas are benign epithelial tumours which can occur on many species of fish from both fresh-water and marine habitats in widely scattered geographical areas.

Most papillomatous epithelial lesions are presumed to have a viral or partly viral aetiology. Environmental factors have also been found to contribute to the condition.

Notable examples include:

Carp Pox

Atlantic Salmon papilloma

'Cauliflower disease' in the European eel

Clinical Signs

Clinical signs can vary from small raised nodules to large, grey-to-black epithelial growths.

They are usually multiple and can appear in any location of the body.

Other clinical signs are only seen if the nodules restrict the fish's ability to feed.

Tumours grow at different rates, sometimes dependent on environmental temperature or the host's immunity.

Diagnosis

Diagnosis is usually made on the basis of the clinical signs.

Histopathology will reveal epithelial hyperplasia.

Electron microscopy may reveal viral particles or viral inclusion bodies, but this does not occur in all cases by far.

Treatment

No treatment is usually necessary. Their major problem is the disfigurement they cause.

Surgical removal is possible if the growths are obstructing the fish in any way.

Papilloma - Fish Learning Resources
Flashcards Test your knowledge using flashcard type questions	Ornamental Fish Q&A 24

References=

Hoole, D. (2001) Diseases of carp and other cyprinid fishes John Wiley and Sons

Roberts, H. (2009) Fundamentals of ornamental fish health John Wiley and Sons

Roberts, R. (2001) Fish Pathology Elsevier Health Sciences