VETS have expressed concern following the announcement by the Veterinary Medicines Directorate that a popular anthelmintic parasite control product for sheep has been reclassified to allow it to be prescribed through agricultural merchants who employ pharmacists or 'suitably qualified persons'.

Citing concerns over the growing problem of parasites with resistance to anthelmintics, the vets insisted that any move to loosen control on the active ingredient's use – and potentially abuse – was going against the flow of veterinary medicine legislation elsewhere in Europe.

At issue is Startect Dual Active Oral Solution, a 'group 4' anthelmintic from Zoetis which has officially been reclassified from being a veterinary prescription only medicine to one that can be sold by vets, pharmacists or SQPs from August 24 this year – a move that both the British Veterinary Association and the Sheep Veterinary Society have questioned.

BVA junior vice president John Fishwick said: "We know that resistance to anthelmintics is increasing in grazing animals worldwide and needs to be addressed to avoid a potentially disastrous situation of being unable to tackle parasites.

"The reclassification of Startect Dual Active from POM-V to POM-VPS is in direct opposition to the trend in Europe, where we are seeing increased control over dispensing of anthelmintics in species where resistance is posing a serious threat to animal health, welfare and profitable production – we are extremely concerned that we might start seeing resistance develop in Group 4 as a result.

“BVA believes that the prescribing of anthelmintics requires a level of control best provided by a veterinary surgeon who has the animals under his/her care, and is based on a sound clinical diagnosis," said Mr Fishwick. "The drugs are best used as part of a flock health plan drawn up by farmers in conjunction with their vet in order to protect animal health and welfare and safeguard the efficacy of these products for the future."

SVS president Kathryn Dun said: “Group 4 anthelmintics should be used only as part of a careful designed strategy for the individual farm and it is imperative that this strategy is worked out with a vet and is part of a flock health plan for that farm. The products need to be used, in the correct way, to help prolong the life of our other anthelmintics.

“We are unlikely to have any further new groups of anthelmintics in the foreseeable future, so education of those buying and selling these products is crucial to ensure the longevity of the effective action of them against sheep parasites.”

However, Zoetis vet Dr Dave Armstrong insisted that the product had its own defence against resistance: “The benefits over a single active are vast because it not only kills worms resistant to other products, but used routinely, as part of a parasite control plan, can help delay wormer resistance. This will help protect your flock from drench failure now and into the future.”