Real-time updates on blowfly risk – produced via an ongoing collaboration between Elanco and the National Animal Disease Information Service (NADIS) – now show the risk level is “severe’ across all regions of the country.
Richard Wall, Professor of Zoology (Ectoparasite Specialist) and compiler of the Blowfly Risk Alerts, said: “Despite the cooling temperatures, extremely high blowfly populations and damp conditions mean that strike risk remains severe across the UK and is likely to remain high for the next few weeks. Since treatment applied to ewes after shearing may now be nearing the end of its period of active protection, considerable care is needed to avoid serious cases of strike.”
Regional Alert breakdown
| Region | Score |
| NW Scotland | Severe |
| E Scotland | Severe |
| NE England | Severe |
| E Anglia | Severe |
| The Midlands | Severe |
| S England | Severe |
| SW Scotland | Severe |
| NW England | Severe |
| N Wales | Severe |
| SW England | Severe |
| S Wales | Severe |
| N Ireland | Severe |
NADIS Map key:
Low risk: No significant risk
Medium risk: One in 2,500 animals might be struck
High risk: One in 500 animals might be struck
Severe risk: One in 100 animals might be struck
Kate Heller, Elanco’s ruminant technical consultant, said that farmers are being urged to ‘strike first’ with preventative treatments rather than risk devastation to their own flock.
Using protection early reduces risk later in the season by ensuring a much lower fly count as the season progresses.
Ms Heller said: “A lot of farmers think “it’s not in my control” because of bad weather or other circumstances. They’re unnecessarily putting limits on themselves. Blowfly strike is not an inevitable part of farming and can be mostly avoided with the right management strategy.
“When farmers are looking at treatment options, they need to look for the longest protection with an IGR that binds to the fleece – It is now possible to get 19 weeks blowfly strike prevention. There are no guarantees when it comes to blowfly strike – with significant levels identified into November, an essential part of any strategy, has to ensure an early treatment that extends right through the long season.”
National Farm Research blowfly study
Results of an Elanco blowfly study conducted in partnership with the National Farm Research Unit found that 99% of farmers having suffered financial losses as a result of blowfly strike. While 82% agree that the blowfly season is getting longer, with cases of strike being reported as early as February and as late as November.2
The cost
The consequences of blowfly strike can be devastating, leading to production losses and welfare problems. By comparison, preventing blowfly strike using a long-lasting product can offer not only peace of mind but can also be economical in terms of time, money and effort.
| Blowfly strike: financial losses | Compared to blowfly treatment |
| £200 – breeding a replacement ewe | |
| £80 – loss per lamb death | |
| £10 – production loss per struck lamb | |
| £10 – labour costs handling struck animals | Treatment – 50p per animal |
