TWENTY-SECOND ANNUAL EASTERN FISH HEALTH WORKSHOP ROYAL PAVILLION RESORT, ATLANTIC BEACH, NC MARCH 18 - 20, 1997 Mycobacteriosis in Desert Gobies at a Zoo Aquarium S.D. Fitzgerald1, DVM, PhD, Gary L. Watson1, DVM, PhD, and Dalen Agnew2, DVM 1Animal Health Diagnostic Laboratory & Dept. of Pathology, College of Veterinary Medicine, Michigan State University, East Lansing, Michigan. 2Detroit Zoological Park, Royal Oak, Michigan. Over a 3 year period an aquarium in a zoologic park had chronic disease and high mortality in several species of fish in multiple exhibit tanks. Species included: Muzquiz Platy (Xiphophorus meyeri), Carco la Palma Pup Fish (Cyprinodon longidorsalis), Golden Skiffia (Skiffia francesae), Mexclapique (Girardinicichthys viviparus), and Desert Goby (Gobius sp.). This case report will concentrate on the Gobies. Ten Gobies in a 20 gallon aquarium exhibited rapid labored respiration, fin rot, skin ulceration, darkening of skin coloration, emaciation, and multiple prominent swellings. Treatment of the water with formalin (25 mg/L) had no effect. Fish were submitted to the Animal Health Diagnostic Laboratory for histologic examination. Histologic serial sections of the fish revealed ulcerative and granulomatous dermatitis, granulomatous myositis, proliferative and granulomatous branchitis, granulomatous enteritis, and multiple granulomas within the kidneys and livers. All lesions were associated with long acid-fast bacilli, consistent with Mycobacterium sp. Attempts at mycobacterial isolation from the water and tissues have been unsuccessful. As mycobacteriosis is difficult to treat, and presents a human health hazard, all affected tanks have been depopulated and disinfected. The water source for the aquaria is being evaluated for water quality and possible new water sources are being explored to help decrease the incidence on mycobacteriosis in the future. Return to 22nd Annual Eastern Fish Health Workshop Return to Leetown Science Center Home Page