Sheep Fly Strike Prevention Welfare

Blowfly strike (myiasis) is one of the most painful and distressing conditions affecting sheep. Prevention through monitoring, treatment, and management is a welfare priority during the fly season.

Key Facts

An estimated 1-3% of the UK sheep flock is affected by blowfly strike annually
Strike can progress from egg laying to severe tissue damage in 24-48 hours
Lucilia sericata (greenbottle fly) is the primary cause in the UK
Insecticide treatments provide 6-16 weeks of protection depending on product
Dagginess (soiling around the tail) and wounds significantly increase strike risk

Welfare Considerations

Blowfly strike causes extreme suffering — larvae tunnel into living tissue, releasing enzymes that liquefy flesh while the sheep remains alive and potentially unable to escape or signal distress effectively. Early strike appears as restlessness and biting at affected areas; advanced strike involves obvious tissue destruction and systemic toxaemia. The welfare imperative is prevention and daily observation during the fly season (May-October in the UK). Insecticide treatment of at-risk animals, prompt removal of dagginess, and daily flock observation enable early detection and treatment before severe welfare harm occurs.

What You Can Do

Ensure sheep receive appropriate insecticide treatment at the start of and during the fly season
Inspect the entire flock daily during warm months for signs of restlessness or strike
Treat dagginess promptly to remove the primary strike attractant
Contact your vet immediately if you find a struck animal — rapid treatment reduces suffering
Advocate for fly strike prevention to be explicitly included in sheep welfare codes of practice