Updated: Mar 13
Thrush involves disintegration of the frog, clefts, and sole of the hoof, and is characterized by a black discharge and offensive odor. Some of the causes of thrush are unclean stabling conditions, insufficient foot expansion, failure to properly clean the hoof, and lack of frog pressure, all of which allow infection to develop.
When a horse is treated for thrush, he should first be stabled on a clean, dry surface, and his feet thoroughly cleaned with disinfectant. The affected parts of the frog should then be trimmed away and the hoof treated twice daily with one of the various thrush treatments, many of which contain a form of iodine. A suitable thrush dressing may by made by mixing one part formalin with three parts water.
For mild cases of thrush, drying solutions like Kopertox and a dilute formalin solution can be directly applied to the sole of the hoof. Other astringent medications that may be used include chlorine bleach, calomel, anti-inflammatory packs, and cotton soaked in a 10-20% sulfapyridine solution and packed into the affected area. Later, corrective shoes with bars may be used to provide adequate frog pressure. If thrush affects the sensitive structures of the foot, tetanus antitoxin or toxoid should be given.