'Promising' signs in fight against sheep scab

The disease, which is endemic throughout the world, was eliminated from the UK 40 or 50 years ago through a rigorous dipping campaign and the use of organophosphate (OP) chemicals.

However, the removal of compulsory dipping and the side-effects of using OP dips allowed the disease back into the country and in recent years it has quickly spread through all the sheep-producing parts of the country.

Sarah Hall, a PhD student at Edinburgh University, said yesterday that there was now no way of knowing just how widespread the problem is, as it is no longer a notifiable disease.

However, she estimated that about 40 per cent of all sheep flocks in Scotland now had the disease within their numbers.

What she and anyone in the livestock business knows is that the parasitic mite that causes the problem by living on the skin of the sheep can cause a major animal welfare problem as well as markedly reducing live weight gains.

Symptoms include a constant scratching, which, in severe infestations, can result in broken areas of skin and massive lesions.

Current sheep scab control operations are not very effective and so, as part of a Quality Meat Scotland-funded project, Hall is working on finding a remedy that is both safe to use and effective.

Her research work is based on identifying and then using bacteria which are associated with sheep scab and the effect these bacteria could have on the parasitic scab mites.

Through this research, Hall hopes to produce a bactericide which can then be used as a spray to kill the mites. The technique behind using this already operates in the United States, where a bactericide is used to prevent the growth of bacteria on meat.

"It is still early days, but there is a lot of potential. This type of approach is very specific and there are no negative side-effects. We have already proven that mites fed with microbials have much shorter lives than those living normally on sheep."

She was unwilling to give any timescale on her work, other than saying there was at least another six months of work in refining the technique and in further research.

One of the major problems for this research work has been the lack of a ready supply of mites, and yesterday Hall asked if farmers who thought they had the disease in their flocks could send skin scrapings to her.

Hall's research is one of the 47 projects currently being funded by QMS. Many are collaborative projects between research institutes. The work being carried out ranges from animal health and welfare issues through to the retail side of the red meat sector in Scotland.

Professor Charlotte Maltin, science and innovation manager at QMS, said they had invested 220,000 from their side, but that figure could be multiplied tenfold through the collaborative approach.

There were two main fields of work being carried out, she added. The first related to improving efficiency of production which meant that any aspect where losses were being made came under that title.

The second main target for this red meat promotional body related to research on the eating quality and marketability of the meat produced in Scotland.

To donate skin scrapings, anonymously if you wish, e-mail