Egg counts key to gut worm control

Sheep farmers are being urged not to panic when faced with new gut worm outbreaks amid reports they are becoming more prevalent.

Also known as Barber’s Pole worm, haemonchus is no longer a problem restricted to the south of England. Given the right conditions – usually warm and wet weather –outbreaks are occurring across the country

Clinical disease

“We can see clinical disease from spring right through to mid- to late-autumn, and as weather patterns change, this could change further yet,” said farm vet Dawn Bowness, from Clevedale Veterinary Practice in North Yorkshire.

A similar warning was given by farm vet Kaz Strycharczyk, from Black Sheep Farm Health in Northumberland. Both vets sounded the warning on an episode of the Webinar Vet’s podcast Vet Chat.

Clinical signs of haemonchus differ from other gut worms because it does not cause scouring, said Dr Strycharczyk. He added: “Signs of sub-acute and chronic disease include bottle jaw, pale eye membranes and ill thrift.”

Dr Bowness recommends extending faecal egg count (FEC) monitoring programmes to include adult ewes. High egg counts often indicate Haemonchus problems – although this needs to be confirmed with species testing in a lab.

“Often Haemonchus catches farmers out as there’s a field of sheep that aren’t scouring, but when they’re put under some pressure, such as being gathered or moved, the anaemia they’re quietly suffering becomes too much for them.”

In flocks where Haemonchus has been confirmed, farmers are advised to speak to their vets about the most appropriate treatment and to follow the same treatment principles as they would for other parasite problems.

Dr Strycharczyk said: “In an acute outbreak where there’s multiple dead sheep, I’d generally recommend going in and treating everything in that mob, and doing a post-drench check seven to 14 days later to make sure treatment has worked.