Operators of mobile sheep shower units have been called into question by a local vet and sheep scab expert.

Speaking in Coleraine on Tuesday, Paul Crawford pointed out that the only dip product available in NI for external parasite control, known as Gold Fleece, is not licensed for shower units.

“It is illegal to use it in those units. Authorities here [in NI] are supposedly planning to clamp down on it, similar to what is being done in Britain,” he said.

Crawford said he received a phone call from a shower unit operator who challenged similar comments he made at a public meeting last week.

“I told him that across the national flock, showers will not be able to eradicate sheep scab,” he said.

Scab is caused by mites and the dip from shower units does not reach all parts of the sheep, so some of the mites can survive treatment.

This leads to further spread of the disease and, more worryingly, creates the opportunity for mites to become resistant to the dip.

Gold Fleece, which is an organophosphate (OP)-based dip, is only licensed for use in plunge dippers, as it gives full coverage and therefore kills mites on all parts of the sheep.

“We already have some mites that are resistant to injectable wormers, so if they become resistant to OP-dips too, then we have nothing left as a treatment for scab,” Crawford said.