Polycystic kidney disease in goldfish (Cusrassius auratus)

Abstract Thirty percent of 60 goldfish in an outside pond showed progressive development of swollen abdomens and floatation problems. The occasional fish was found dead. Necropsy of an affected fish showed an abdomen almost filled with a large bilobed ventral mass comprised of masses of cysts filled with clear fluid. On histopathological examination, this mass appeared to be composed of large cystic spaces lined by a single flattened epithelium. Occasional remnants of normal kidney tissue were seen withen the mass.