Sheep Scab: Early action is key to protecting your flock

Commodity Watch written by UFU policy officer, Kayleigh Ashton-Meek

Sheep scab continues to pose one of the greatest health threats to the sheep industry in Northern Ireland. Although the disease is commonly associated with the colder months, veterinary reports show that cases are increasingly being identified throughout late summer, making year-round vigilance more important than ever.

One of the biggest challenges with sheep scab is that infected animals may appear perfectly healthy while still spreading the disease. During this early or subclinical stage, mites can be transmitted to other sheep for several months before obvious signs such as itching, wool loss or skin irritation become apparent. By the time clinical symptoms develop, the disease may already have spread within the flock or to neighbouring farms.

The Pilot Sheep Scab Project, delivered by Animal Health and Welfare Northern Ireland (AHWNI) between 2022 and 2023, highlighted just how widespread the disease is across the province. The findings suggested that infection levels are considerably higher than previously recognised, reinforcing the need for greater awareness and improved disease control. Although this project has since ceased, anybody working within the sheep industry is reminded that AHWNI provide key information on the signs to look out for, diagnosis and treatment of Sheep Scab on their website (https://animalhealthni.com/health-programmes/sheep-scab/).

Farmers should regularly inspect sheep for signs of excessive rubbing, biting, fleece damage or restlessness, particularly after purchasing new stock or returning animals from grazing or livestock marts. Any suspicion of sheep scab should be investigated promptly. As sheep scab is a notifiable disease, suspected cases must be reported to DAERA by contacting the DAERA helpline on 0300 200 7840 or through the local DAERA Direct Regional Office (https://www.daera-ni.gov.uk/contacts/daera-direct-regional-offices). While movement restrictions are applied to affected flocks, these are temporary and are lifted once appropriate treatment has been completed. Early reporting helps limit disease spread and protects both individual businesses and the wider sheep sector.

Controlling sheep scab has become increasingly challenging due to resistance developing against some commonly used injectable treatments. Products containing ivermectin have become less reliable in certain situations, making correct treatment decisions more important than ever. Where injectable medicines are used, sheep should always be weighed accurately to ensure the correct dose is administered, reducing the risk of treatment failure and slowing the development of resistance.

Plunge dipping remains the gold standard for eliminating sheep scab mites. However, the use of organophosphate (OP) dips is tightly regulated and requires appropriate training and certification. Farmers who are unable to dip themselves can employ accredited mobile dipping contractors, who are trained to safely handle, apply and dispose of sheep dip in accordance with current regulations.

Biosecurity also plays a vital role in preventing disease transmission. Livestock marts are an essential part of the sheep industry, but they also create opportunities for diseases to spread between flocks if appropriate precautions are not taken. Farmers should never transport sheep showing signs of infectious disease or those suspected of carrying sheep scab. Equally important is ensuring trailers, handling equipment and clothing are thoroughly cleaned and disinfected after use.

Introducing purchased sheep directly into the main flock remains one of the greatest disease risks on many farms. Newly arrived animals should always be quarantined in a separate, clean area and monitored carefully before joining resident stock. This simple step can help identify health problems before they become costly flock-wide outbreaks.

Strong biosecurity, prompt reporting and effective treatment remain the foundations of sheep scab control. By remaining alert throughout the year and taking sensible preventative measures, farmers can reduce the impact of this costly disease and help improve sheep health across Northern Ireland.