Abstract

Fish maintained under human care may have long lifespans as a result of advances in veterinary medicine and husbandry. Neoplasia, therefore, is not uncommon in managed aquarium populations. However, few studies have systemically evaluated neoplasia in managed fish populations.^1–7 The objective of this study was to retrospectively review and categorize neoplasia in fish at a large public aquarium between 2005 and 2021. Any fish diagnosed with neoplasia on either antemortem or postmortem evaluation during the study period was included and all medical records and pathologic reports were reviewed. Sixty-four animals met the inclusion criteria. Thirty-nine different species were included in the study population, most of which were tropical freshwater fish (n=33). Prevalence of neoplasia averaged 0.07% in the study population. Twenty-nine types of neoplasia were identified, of which 8 (27.5%) were benign, and 21 (72.5%) were malignant. Twenty-four (37.5%) cases had evidence of metastasis. Unique cases seen included fish with esthesioneuroblastoma and dysgerminoma. This study contributes to the overall knowledge of the health of aquarium fish and may aid clinicians in characterizing neoplasia that may be present in fish under human care.

Acknowledgements

The authors thank Kristi Heffron for her contributions to this study, the aquarists, and the Animal Health team members for their dedication to animal care.

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