COLUMNARIS DISEASE
columnaris disease: translation
a systemic and skin disease of young-of-the-year freshwater fishes caused by Flexibacter columnaris (or Flavobacterium columnare). Usually occurs in summer and is associated with stress, crowding, injury and poor water quality. Virulent forms may show no external symptoms, less virulent forms show grey-white lesions on the body, fins and gills. Lesions first appear on the caudal fin and progress towards the head. Heavy infections appear yellow or orange. Scaleless fish show lesions comprising a dark blue area overlain by a milky veil and with a red-tinged margin. See also saddleback, saddlepatch disease, mouth fungus and mouth rot, depending on locality on body