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New map reveals blowfly strike reported across the UK

Sheep farmers nationwide are reporting the first incidences of blowfly strike in their regions, warning other farmers the parasite is threatening flocks across the UK.

The strike cases have been plotted into a new ‘strike tracker’ map, produced by Novartis Animal Health, which shows the areas where strike has currently been reported

Fiona Lovatt, president of the Sheep Veterinary Society, says: “Due to the unpredictability of the UK weather, getting the timing right for treatment of ewes and lambs against blowfly strike can be extremely difficult. Incidence of blowfly strike will rise with the local soil temperature on a farm, and some areas of a farm may be warmer than others.

“Many do not realise the speed in which blowfly strike can occur, as within days of emerging, adult females lay batches of about 200 eggs onto the sheep’s fleece. If an infestation is missed, the sheep will suffer for a week or so before dying.

“Thankfully, blowfly strike can easily be prevented but research has shown there is a very good reason to use such treatments early in the year to prevent a build-up of flies and avoid the devastating impact strike can have on flocks.”

Fiona Anderson, vet adviser at Novartis Animal Health adds: “Prevention is always best in the case of blowfly strike because adult flies can lay so many eggs in the fleece and the strike can establish very quickly

Farmers have so many demands on their time it can be easy to miss an affected sheep. An infestation can be easily prevented through the use of products which contain insect growth regulators.

“These inhibit the development of the damaging second- and third-stage maggots which are responsible for causing fly strike and stock damage.”

Blowfly strike

  • Caused by the infestation of sheep by fly maggots which feed directly on the skin of affected animals, causing serious distress and welfare problems and in some cases death
  • In the UK, blowfly strike occurs on over 80 per cent of sheep farms
  • To report a case of strike in your region, farmers should email:

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