Sheep farmers need diagnostic help for better footrot control

Sheep producers need to be able to distinguish between scald, footrot and contagious ovine digital dermatitis (CODD) before they can implement the most effective foot condition control strategies.

That's the advice from a group of vets, scientists and advisers after a late summer sheep footrot workshop organised by SAC Veterinary Services at the Moredun Institute in Edinburgh.

"Effective diagnosis of these different foot conditions is crucial," points out workshop co-ordinator Brian Hosie, veterinary manager at SAC. "The different conditions can be confusing, so farmers need proper veterinary advice. Too many sheep producers leap to their own, often incorrect, diagnostic conclusions and then ask their vet for antibiotics to treat the problem.

"For example, vets correctly prescribe antibiotic injections to treat virulent footrot lesions, but their effect on scald is minimal and they have no role in the prevention of footrot," Brian says.

To help farmers better understand the different foot conditions, the workshop participants agreed the following definitions: scald is a 'between the hooves' problem, footrot is a 'hoof' disease with under-running of the hoof and the typical smell, and CODD is a disease of the coronary band and is best defined as an 'over the top of the hoof' problem. The extent of CODD is unknown in the UK, but the workshop consensus was that it was becoming a more significant problem.

According to Kym Abbott from the Royal Veterinary College, CODD starts in the coronary band but quickly under-runs the wall of the hoof. "It is characterised by the involvement of the outside wall of the hoof - rather than the sole - a tendency to bleed easily and the lack of a footrot smell," he points out.

Another workshop participant Neil Sargison from the Royal (Dick) School of Veterinary Studies provided further support for the need for improved diagnosis of sheep foot problems. He stressed that footrot management advice, in particular, should also distinguish carefully between those methods which are useful for treating severely affected sheep - such as trimming and parenteral antibiotics - and those which help control and prevent disease when used correctly - such as footbathing and vaccination with Footvax.

"The objective of good footrot control is to prevent the development of new cases by using methods which are cost-effective and not too labour intensive. If this objective is met, very few sheep in the flock will develop severe under-running infections and require individual treatment," he says.

"Advisers should encourage their sheep farmer clients to identify the high risk periods for disease transmission and institute effect control strategies such as footbathing and vaccination at the time disease transmission is expected to commence. We have also seen evidence of treatment benefits from vaccination, particularly in the autumn."

The aim is to take the diagnosis, treatment and control recommendations from the meeting to farmers and their advisers this winter and the following spring.

Footrot Disease Management - Practical Checklist

* While footrot remains the most common cause of lameness in a

flock, there are other causes of lameness. Seek veterinary advice and ensure you have an accurate diagnosis before commencing any treatment or control programme.

* Footrot is a flock problem and the aim should be to

continually control its spread within the flock.

* Employ control measures (regular footbathing with 3%

formalin or 10% zinc sulphate) where the level of footrot is low (<5%). If the level of footrot is greater, implement additional control measures. Vaccinate with Footvax before disease transmission.

* Treat any lame sheep (antibiotics and vaccinate) to cure the

problem, but accept that some will be incurable and must be culled.

* Foot paring is not a part of general footrot control. It

should only be used sparingly to maintain the integrity of the foot and must never be so drastic that it draws blood

For further advice, consult your vet or farm adviser.