Beware sheep sales for scab risk

Early-season sheep sales are a timely reminder for farmers to be aware of the risk that bought-in sheep pose for scab infestation.

Autumn sheep movements are a serious transmission route for sheep scab infestation, although symptoms may not show for several weeks or months, says Pfizer vet Dave Gilbert. By following the Sustainable Control of Parasites in Sheep (SCOPS) three-step plan for all bought-in sheep and those returning from tack, he says farmers can minimise the risk to their own flocks from both sheep scab and anthelmintic-resistant worms.

First, all new and returning sheep should be yarded for 24 to 48 hours while they are treated. Second, all sheep should be treated with an injectable macrocyclic lactone medication at the dosage rate for sheep scab and, at the same time, a levamisole (yellow) drench.

Then 24 to 48 hours after treatment, sheep should be turned out on to pasture that has already carried sheep this year. New arrivals should be kept separate from all other sheep on the farm for at least three weeks.