Sheep farmers have been told to be prepared to deal with the threat of blowfly strike as the weather warms up

Wendy Phillips, a vet with the Arrowfield Veterinary Group, in Herefordshire, said both ewes and lambs will be at risk, especially if they are dirty, as weather conditions change.

“Blowfly can emerge very quickly, with eggs hatching within 12 hours. The advice is now to treat your flock and treat them early. Some thought is needed when choosing the most appropriate pour-on at this time of the year.

Helen Langham, Product Manager with Novartis Animal Health, said she had already received reports of strike earlier this month at a farm near Saltash on the Cornwall-Devon border, with another report coming in last week of a strike case further up the country in Worcestershire.

“The message for dealing with blowfly is to treat preventatively. We had some reports of strike as early as March but things then went quieter during the colder wet period. Farmers should not be lulled into a false sense of security though. Now the weather is warming up again, we will see optimum conditions for strike,” she said.

Novartis also identified a significant risk from nematodirus due to changing weather patterns last week.