[Causes of disease and death in ornamental fish--frequency and importance]

Between 1986 and 1990 1068 aquarium fishes from breeders, wholesale dealers and pet shops and from private owners were examined. In 45% of the cases different non infectious causes of illness or death were detected. Infectious causes were present in 38%. 14% of the fishes showed no pathologic symptoms, whereas 3% of the samples were unfit for examination. The frequency of infectious and non infectious diseases respectively in fishes from breeders vs. dealers vs. private owners is given. From these results factors of pathogenesis in aquarium fishes are discussed and compared to those in fish breeding for food fish. Advices for prevention of diseases in fancy fishes are given.