During the course of the experimental culture of the short-finned eel Anguilla bicolor bicolor McClelland
in running water at Mandapam Camp, seven kinds of diseases namely Fungus disease, Tail fin rot disease. Gas disease, Red pest and botches disease, swollen intestine disease. Gill disease and Cripple body disease were identified. The fungus disease was observed in elvers on their body surface as an outgrowth of whitish or grayish mass, spreading from the affected region. The tail-fin rot disease was noticed both in elvers and in growing eels and the affected portion gradually spreads due to the activity of the causative bacteria resulting in putrefactio