Columnaris disease, caused by Flavobacterium columnare, is commonly called Saddle Back Disease or Cotton Wool Disease. It spreads rapidly in warm Nigerian ponds above 25°C and can kill 50% of a stock within 72 hours in acute outbreaks.
Flavobacterium columnare is a filamentous gram-negative bacterium that forms characteristic column-shaped clusters under a microscope — hence the name Columnaris. It attacks external tissues first: skin, fins, and gills. In the acute form common in Nigerian ponds, internal organs can be affected within 48 hours.
The bacterium thrives in warm, hard water with high oxygen demand — conditions typical of dry-season Nigerian ponds with high stocking density.
Salt is the first-line treatment. Columnaris is sensitive to salt at therapeutic doses. Apply iodine-free salt at 3g/L and maintain for the full treatment period even if fish appear to improve after Day 3.
Copper sulphate is effective against Flavobacterium. Apply at 0.5–1mg/L as a pond treatment. Do not use in ponds with soft water (hardness below 50mg/L CaCO₃) — it becomes toxic to fish. Available at agricultural chemical suppliers in major Nigerian cities.
An effective alternative to copper sulphate. Apply at 2mg/L as a single treatment, then repeat after 72 hours if lesions persist. More forgiving in soft water conditions.
For moderate to severe outbreaks, add Oxytetracycline to feed at 50mg/kg body weight for 5–7 days to prevent systemic spread.
The treatments differ significantly. MyFishDoc AI Doctor identifies which one your fish has based on exact symptom patterns.
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