Barber's pole worm spread prompts warning to sheep farmers

Sheep farmers are being urged to step up worm monitoring in adult ewes as Barber’s pole worm becomes increasingly prevalent across the UK.

But a high faecal egg count should not automatically trigger treatment for *Haemonchus contortus*, with farmers advised to establish which worms are responsible before choosing a wormer.

Elanco ruminant technical consultant Matt Colston highlighted one farm where faecal egg counts ran into the thousands, but *Haemonchus* accounted for only 10% of the result.

He said: “Using a narrow spectrum wormer in this case wouldn’t have been the best option as it would have left a significant burden of other strongyles behind.”

Farmers who suspect *Haemonchus* are being advised to speak to their vet about appropriate diagnostic testing before deciding on treatment.

Options can include laboratory testing of samples, FAMACHA testing — which examines the colour of the lower eyelid to estimate anaemia — and post-mortem examinations.

Confirming that *Haemonchus* is present can help farmers introduce more targeted monitoring in adult ewes and intervene before serious problems develop.

Mr Colston said: “Knowing *Haemonchus* is present means you can put in some checks for adult ewes, such as some mob worm egg counts at routine handlings, and intervene, if required, before any serious problems occur.”

Interpreting pooled faecal egg counts can also be difficult, as a high result may be driven by only a small number of sheep within a group.

“If you get high egg counts from a mob sample, just one or two animals in the pool could be responsible for driving that number up,” Mr Colston said.

He added: “A discussion with your vet or adviser will help you decide if group treatment or just treating some individuals in the group is the best course of action.”

Treatment choice will vary between farms depending on the worms present, resistance risks and the circumstances of the flock.

Broad-spectrum treatments such as monepantel may be appropriate in some situations, while other active ingredients or treatment groups may be more suitable elsewhere.

Farmers are therefore being encouraged to discuss treatment options with a vet or suitably qualified person rather than relying on egg-count results alone.

The situation is generally more straightforward in lambs, which have not yet developed the same level of immunity to gastrointestinal worms as most adult sheep.

“For lambs the picture is simpler as they have not yet developed the level of immunity to gastrointestinal worms seen in most adult sheep,” Mr Colston said.

As a result, farms are more likely to carry out routine faecal egg counts in lambs and treat them before visible signs of disease develop.

The latest advice is for farmers to extend that monitoring mindset to ewes, using routine egg counts where appropriate and confirming whether *Haemonchus* is present before deciding how to treat.

Working with vets and advisers on a flock-specific monitoring plan can help farmers target treatment more accurately and reduce the risk of serious worm burdens developing.