abstract
An adult female green moray eel (Gymnothorax funebris) was evaluated for a two month history of chronic regurgitation. Although appetite and behavior remained normal, whole food items were found in the tank 12-24 hours following each feed. The initial procedures, performed under general anesthesia using MS-222, consisted of radiographs, ultrasound, CBC/chemistry panel, fecal analysis, and gastric endoscopy.1 Endoscopic evaluation revealed multifocal proliferative mucosal masses in the mid-stomach. Biopsies showed gastric mucus gland hyperplasia; no inflammation, neoplasia, or infectious etiologic agents were noted.2,3 The eel was treated with oral metoclopramide to stimulate intestinal motility and prevent further regurgitation. The patient responded well to therapy and regurgitation resolved. A follow-up endoscopy was performed five months later, and additional biopsies were obtained. A clinically healthy conspecific eel was also evaluated using endoscopy to compare with the gross and histopathologic findings. The healthy eel had no gross or histologic gastrointestinal abnormalities. Biopsies in the patient showed no change in the hyperplastic gastric lesions, as well as mild enteritis and intestinal nematodiasis4. The patient was treated with fenbendazole and clinically continued to do well5. A year after initial presentation, the animal died of unrelated causes. Necropsy revealed coelomic gastric adhesions which likely contributed to the chronic regurgitation. The gastric proliferative lesions were shown to be metaplastic changes associated with degeneration and necrosis of gastric pit mucosa without significant inflammation; no evidence of specific etiologic agents was seen. Gastrointestinal endoscopy is a useful diagnostic tool for examination and biopsy collection in eel species.
acknowledgements
The authors wish to thank the entire endoscopy team at the Westerly Hospital in Westerly, Rhode Island for all their support, endoscopy guidance, and donation of their equipment and time.
References
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