Traditionally sheep’s feet have been trimmed to return overgrown horn to the flat of the sole, to open up foot rot lesions, to neaten up foot shape and to open up shelly hoof cavities.
Current thinking is only two of these reasons are actually valid, says Emily Gascoigne, vet with Synergy Farm Health covering Somerset, Dorset and East Devon.
In a recent study by the University of Warwick, sheep were examined to see whether they developed foot rot because they had long feet, or whether sheep with foot rot consequently had longer horn.
“Farmers will know that usually when we tip over sheep with foot rot we often find there is something to trim, but this study proved sheep with foot rot place less weight on their sore foot and so the horn becomes overgrown as it is worn down at a slower rate,” explains Miss Gascoigne.
“The study found if sheep with foot rot were left untrimmed but treated with injectable antibiotics, the horn quickly re-regulated itself - so no trimming was required.”
Previously, foot rot lesions were treated by trimming, to open up the lesion, let the bacteria breathe and to make feet bleed to return to healthy tissue, she says.
“However, studies have shown using an antibiotic spray with extensive trimming is not as effective in comparison to the positive results of injectable antibiotics alone in the treatment of foot rot.
“In fact, trimming has been shown in other studies to increase lameness and delay healing.
“We regularly see toe inflammation and lesions caused by overzealous foot trimming, which are difficult to cure and can cause long-term lameness in sheep.”
Many will be surprised to discover there have actually been no studies to prove the benefit of foot-trimming for foot rot, says Miss Gascoigne.
“Shelly hoof is a tricky lesion and is the only lesion that, as a vet, I recommend trimming for.
“Many sheep display the all too familiar cavities up the side of the hoof, which often require trimming to open up the cavities and to prevent impaction with soil.
“As a general rule, if the sheep is not lame, leave the feet alone, and if you do need to trim due to shelly hoof, do not trim into tissue which bleeds.”
Most farmers still insist on trimming feet prior to sale and show and vets do understand the importance of presentation of the final product, says Miss Gascoigne.
“Always ensure sheep are properly restrained during the foot inspection to minimise struggling and the risk of bleeding, and trim minimal amounts of horn.
“Never transport lame sheep and foot bath all incoming sheep to prevent introducing contagious ovine digital dermatitis, which is a severe infection of the foot, or a more aggressive form of foot rot.
“Contact your vet if you wish to discuss the foot health of your flock and appropriate treatments,” she says.