Cutaneous Myiasis (Flystrike) in Sheep

DermatologyOvineNew

Key Points

Cutaneous myiasis (“flystrike”) is a common, painful and potentially fatal condition caused by fly larvae infesting fleece and skin
- Blowflies and screwworm flies are most commonly implicated in different regions around the world
Most commonly seen in sheep in veterinary practice
Risk is highest during warm, humid weather when flies are most active and eggs can hatch quicker
- Other risk factors include breech soiling, urine scalding, open wounds, footrot and dermatitis
Key clinical signs include early behavioural changes (restlessness, tail-shaking, biting) and progresses to inappetence, foul-smelling lesions, visible fly activity and shock in severe cases
Diagnosis is based on the clinical presentation and exam
Immediate treatment with shearing, larval removal, topical larvicides and supportive care is essential to prevent progression
Prevention requires a combination of monitoring, dagging or shearing, fly control and early treatment of disease / injury

Differential Diagnoses

Moist dermatitis
Dermatophilosis (D. congolensis)
Wounds / trauma
Footrot

Educational content only. This factsheet is for general veterinary education and is not a substitute for professional veterinary advice, diagnosis, or treatment. Not for use in an emergency — contact a veterinarian or emergency service. Full disclaimer →