The first blowfly strike cases of 2018 have been reported via the Elanco Blowfly Strike Tracker.

The interactive map produced by Elanco Animal Health and NADIS (National Animal Disease Information Service) highlights areas hit with blowfly strike in real-time, to deliver immediate warnings for farmers, vets and industry professionals.

The first reported incidents were in Hampshire, before spreading across Devon, West Sussex, and Buckinghamshire.

Particularly severe cases include a flock in Dorset, in which 50% of a lamb group have been hit by blowfly strike. Latest reports are in northern England and some initial cases in Scotland.

The blowfly risk forecast suggests that weather conditions from southern England and Wales to the Midlands mean that flies are now active, and females are laying eggs that result in serious welfare and productivity issues.

Richard Wall, professor of zoology at Bristol University, said: “The timing and severity of blowfly strike is strongly influenced by the weather. This is a reminder to farmers that now is the time to act for early prevention. Delaying treatment not only costs the farm but risks the welfare and productivity of the flock. Strike can develop very quickly, with the first maggots appearing within 12 hours of eggs being laid. Don’t get caught out.”

Fiona Hutchings, Technical Vet at Elanco, says, “The costs of inaction when it comes to blowfly strike far outweigh the costs of protection. By the time symptoms show themselves, it’s often too late. It’s easy to overlook even one struck sheep, and blowfly strike can cause huge damage in very little time. In addition, using protection early reduces risk later in the season by ensuring a much lower fly count as the season progresses.”


Preventative advice from NADIS and Elanco:

• If a preventative treatment has not yet been applied, do so ASAP. By using preventative treatment early in the blowfly season, the risk of strike will be dramatically reduced.

• Manage the fly population: Reducing the fly population early in the year by using and IGR has the greatest impact on the challenge to your flock for the grazing season. Flies can lay up to 3000 eggs in a 3 month an IGR will break this cycle.

• Reduce dirty backends - Dagging, crutching and timely shearing are all important.

• Tail docking lambs is a debated but accepted procedure to reduce strike in lowland flocks.

• Be vigilant while checking stock - Check stock daily for any signs of strike; dirty backends, foot rot lesions and open wounds are all good candidates for egg laying sites.


Signs of blowfly strike

• Discomfort

• Irritation/Restlessness

• Separation from flock

• Damp/Discoloured fleece

• Lameness and wounds

• Dull and sick animals

• Dead animals