ONE OF the newest weapons in the fight against worms in sheep has been re-classified so that farmers can access it from local agricultural merchants and not just through vets.

While the British Veterinary Association has voiced concern about the change in the label use of Zolvix (as reported in last week's edition, the Veterinary Medicine Directorate has approved a new distribution classification what is the only group 4-AD monepantel-based wormer drench for sheep.

The reclassification moves Elanco's Zolvix from vet only POM-V sales to POM-VPS. This means that from the July 1 it will be available to sheep farmers across the UK, through agricultural merchants that employ 'suitably qualified persons' (SQPs) or pharmacists, as well as from the veterinary profession who have been sole suppliers since the wormer's launch in 2010.

“The major benefit for the sheep industry is that the reclassification will increase the number of prescribers who can deliver the sustainable worm control message and its importance for the long term viability of the sheep industry,” pointed out Elanco’s ruminant technical consultant, Fiona Hutchings.

“Elanco would like to thank vets who have proactively integrated Zolvix into worm control strategies and will continue to support vets as they are essential to achieving the industry aim of sustainable worm control,” she added.

It will continue to be recommended as part of a sustainable worming strategy with its main focus for use as a mid-late season lamb dose and an incoming stock and movement quarantine drench. Alongside AMTRA, Elanco will be facilitating an extensive prescriber training programme leading up to and beyond the trade distribution date.

What role does it have in sustainable worming?

This is the only broad spectrum wormer with monepantel in the 4-AD group, the 'orange' class of anthelmintics. It is licensed to kill worms that are resistant to: 'white' drenches (1-BZ), 'yellow' drenches (2-LV) and 'clear' drenches (3-ML) and kills closantel resistant haemonchus contortus.

Incorporating monepantel early when levels of resistance are low on farm has shown a positive effect on slowing the speed of resistance development to the older classes of anthelmintics.

What is the correct use of Zolvix for sustainable worming?

It should be used in every flock, once a year to act as a break dose.

The dose is 1ml/10kg and is aimed at the mid-late season break dose – drenching all lambs on farm in the mid to late part of the grazing season, Zolvix has a seven-day meat withhold.

It is a broad spectrum wormer and farmers can be confident when using it as there has been no known resistance diagnosed in the UK.

In addition, by the time lambs reach the mid to late part of the grazing season, most will have received treatments involving one or more of the group 1, 2 or 3 products. Any worms that were resistant to these groups will have survived these treatments and because they can live inside a sheep for months, these survivors accumulate over the season.

Treatment with a highly effective product such as monepantel, will remove these worms, therefore stopping them from reproducing and adding more resistant worms to the overall population. This can help slow down the development of resistance if it is incorporated early into control programmes.

Incoming stock and movement quarantine dose. All sheep coming on to the farm, whether new stock bought in or the existing flock moving back from different grazing, are at risk in terms of AR worms and should be treated on arrival to protect the farm.

For maximum benefit, farmers should start to use monepantel in these two ways now, even if they do not know the AR status to other groups on the farm.

However, if sheep farmers are to get the best from their worming programme, it is important that they do establish their status to groups 1, 2 and 3. The industry needs to optimise the use of anthelmintics and encourage the adoption of sustainable practices so the activity of other groups can be maintained for as long as possible.

Who should I speak to about using it?

Farmers should continue to talk to their vets about Zolvix, but from the July advice will also be available to sheep farmers across the UK through agricultural merchants that employ SQPs or pharmacists, as well as from the veterinary profession.

Advice can also be sought through groups such as SCOPS (Sustainable Control of Parasites in Sheep).