Studies of Hematology and Histology in Labeo rohita Infected with Cutaneous Columnaris Disease

Bacterial disease is extremely common in freshwater fishes caused by primary or obligate pathogens. Most bacterial infections are caused by gram negative and systematic or ulcer forming bacteria seriously through genera Aeromonas, Vibrio, Edwardsiella, Pseudomonas, Flavobacterium and others. Columnaris disease is also commonly known as saddle back disease, cotton wool disease, cotton mouth disease and fin rot. Columnaris disease has been reported worldwide in most species of freshwater fishes with rare infections reported in marine fishes (Tripathi et al., 2003).