Epizootic neoplasia in a managed population of Atlantic bumper fish, Chloroscombrus chrysurus (Osteichthyes: Carangidae), at a public aquarium.

ABSTRACT

Advances in fish medicine and husbandry have increased the average lifespans of specimens in managed aquarium populations. As a result, an increased incidence and variety of neoplasia is expected. This work characterizes diverse neoplasms arising within a managed population of Atlantic bumper fish acquired via repeated collections from the Charleston Harbor region. A total of 76 neoplasms were evaluated histologically from 41 of 45 fish that died or were killed over a 46-month period, including cutaneous hemangiomas and hemangiosarcomas, lepidocytomas and lepidosarcomas, fibromas, vertebral body or cutaneous osteomas, disseminated lymphomas, testicular leiomyomas, cutaneous or branchial fibrosarcomas, myxomas, fibroblastic lepidosarcoma, teratoid medulloepithelioma, ganglioglioma, malignant nerve sheath tumour, cardiac rhabdomyoma, cutaneous rhabdomyosarcoma, soft tissue sarcoma and renal adenoma. Perioral and cutaneous lesions of vascular and scale origin were observed most frequently. Other, often malignant, neoplasms arose within these benign lesions, resulting in extensive local tissue invasion. However, excluding disseminated lymphomas, metastasis was only detected in one case of hemangiosarcoma. These findings suggest early surgical intervention may limit tissue destruction and loss of display quality. This report details a variety of common and rare neoplasms in fish, as well as the first characterizations of neoplasia in Atlantic bumper and ganglioglioma in fish.