נגיעות בכינת דגים (ארגולוזיס)

Overview

The fish louse Argulus is a large, visible crustacean parasite that attaches to the body and fins of pond fish. Koi and goldfish are commonly affected, particularly after introduction of infested fish or plants.

Causes

The flattened, disc-shaped parasite is introduced with new fish, plants or pond water. It clings with suckers and a piercing stylet, feeding on the host and leaving wounds that invite secondary infection.

Signs

Visible greenish translucent discs moving on the skin, flashing and rubbing, red inflamed bite sites, restlessness, weight loss, and secondary bacterial or fungal infections at feeding wounds.

Diagnosis

Diagnosis is by direct observation of the moving parasites on the fish or in the water; the louse is large enough to see with the naked eye.

Treatment & Management

Treatment includes manual removal of visible parasites, organophosphate or other licensed antiparasitic pond treatments, and repeated dosing to break the life cycle. Wound care and antibacterial support prevent secondary infection.

Prevention

Quarantine new fish and plants, inspect arrivals carefully and avoid introducing untreated pond water.