Ornamental Fish Q&A 12

Question	Answer		Article
Describe the lesion.	The photograph shows the gross appearance of the typical ‘fin rot’ lesion. This is part of a syndrome referred to as ‘cold-water disease’ as it is seen most commonly at temperatures of 4–10°C (39–50°F). The lesion shows erosion and loss of the distal section of the fin with swelling and necrosis at the advancing edge of the infection. As the disease organism spreads, the base of the tail (caudal peduncle) may become affected.		[[|Link to Article]]
What is the most probable disease organism involved?	The most commonly isolated organism is Cytophaga psychrophila, although other flexibacteria as well as Aeromonas and Pseudomonas are sometimes involved.		[[|Link to Article]]
Are other factors likely to be implicated in the disease?	Generally, this condition represents an opportunistic infection that is secondary to poor environmental conditions, nutritional problems, or physical damage. Once the infection is established it will spread to healthy tissue on the same fish and will become a source of infection to other fish in the pond. Treatment is aimed at correcting the underlying stress factors. Parenteral antibiotics are of little value, although surface-active agents such as acriflavine and benzalkonium chloride added to the water may help. Raising the water temperature may help because Cytophaga psychrophila does not grow at temperatures above 12°C (53.6°F).		[[|Link to Article]]