Capillaria worms

Signs

• Thin or wasted although eating well
• Weight loss, sometimes a pot belly
• Poor growth in juveniles; poor tolerance of shipping and handling

Cause

Capillaria spp. (e.g. Capillaria pterophylli) and the related Pseudocapillaria tomentosa: thin intestinal nematodes with a direct life cycle (spread fish to fish by eating eggs/larvae). Common in cichlids incl. angelfish and discus; also cyprinids, zebrafish, gouramis, tetras, barbs. Tubifex worms can carry infective stages.

What to do

Dewormers fenbendazole or levamisole. UF/IFAS: fenbendazole only in food (1.14 g per lb of food for 3 days), repeated in 2-3 weeks; levamisole in food (1.8 g per lb food once a week for 3 weeks) or as a 2 mg/L 24-hour bath repeated in 2-3 weeks. Merck: fenbendazole 25 mg/kg in food for 3-5 days. Remove debris and faeces often, especially after deworming. Consult a fish health specialist first.

If a fish is badly ill, talk to an aquatic vet.

Prevention

Check fish for worms (fresh faecal exams) before use and periodically; good sanitation (siphon faeces and debris); avoid live tubifex/oligochaete worms where possible.