The non-bony part of all ungulate (hooved) mammals’  feet is prone to infection by bacteria and fungi, in horses this is called thrush. This can result in destabilisation of the back of the foot, a condition known as sheared heels. Severe thrush can lead to a significant infection in the heel bulb called quittor.


Provision of clean bedding (keeping stable bedding dry is the key to prevention). Good yard and paddock management helps prevent anaerobic bacterial foot infection.  However thrush can still take hold in the clefts and crevices of the frog.

Signs and symptoms

The farrier will note any signs of thrush when trimming the feet.  These include soft, crumbly texture around the frog, moisture and sometimes a discharge.


The farrier will trim the frog and expose the bacteria to air is the first priority. Keep them clean and dry and use peroxide, astringents, specialist disinfectants or topical antibiotics to reduce the bacterial activity..

A cost efficient product is an iodine solution (up to 10%) sprayed onto well cleaned frogs and the cleft every 2-3 days.