7 July 1995

Irish view on sheep scab

BRITISH flockmasters have the tools needed to eradicate sheep scab, claimed Dr Dermot OBrien, head of parasitology at the veterinary research laboratory in Dublin.

Anecdotal evidence suggests there has been a huge increase in outbreaks since compulsory dipping and notification stopped in 1992.

Speaking at the Royal, Dr OBrien said it was up to farmers to act to eradicate a severe and important sheep disease.

"The mites incubation period varies from three weeks to six months, which is the most important aspect in the spread of the disease," said Dr OBrien. "It is a deadly disease and of grave economic importance. There is a 30% death rate when sheep are left untreated and 30% loss in production."

In 70% of cases the disease was spread when sheep were bought on to the farm or stock returned from market. Those passing through dealers were three times as likely to have scab than those traded privately.

Scab had to be treated correctly, said Dr OBrien. When dipping, water should be clean and the dip mixed at the correct concentration for treatment to be effective. At the same time producers should be aware of their own safety and the environmental impact of spreading spent dip.

If using ivomec, sheep had to be injected twice with 2ml/kg subcutaneously. When insufficient dose was administered producers were actually suppressing the disease, said Dr OBrien.

Dr Dermot OBrien: Sheep scab advice for British sheep men.