Thrush is a bacterial infection in the deep grooves (or “sulcus”) of the frog that occurs when wet soil, manure, or bedding is trapped in the sulcus. The trapped moisture is deprived of oxygen and becomes a breeding ground for bacteria. It is important to note that horses are generally not lame and the condition is not painful.
In nature, horses are constantly on the move. This activity serves to naturally clean the hooves when they hit the ground. As horses have become more sedentary and confined to stalls for many hours a day, the natural cleaning process no longer takes place. This is why it is important to pick your horse’s feet daily and ensure that the grooves of the frog are clean.
In most cases thrush only affects the grooves of the frog in severe cases it may include infection of the white line, sole, or other sensitive tissue in the foot.
Causes of Thrush
While wet debris (soil, shaving, manure) trapped in the grooves of the frog and soul of the foot can happen to any horse, horses with a high heels and deep grooves may be predisposed to thrush. Even with the best of care, horses may develop thrush, particularly in wet climates.
Signs of Thrush
1. Presence of a thick black substance in the grooves of the frog that has an offensive odor.
2. If picking the frog elicits a painful response this could mean that the infection has traveled to the sensitive tissue of the hoof, which can result in temporary lameness. If left untreated, permanent lameness can occur.
Preventing Thrush
You can take some simple preventative measures to keep your horse from developing thrush.
1. Offer regular turnout or exercise. This will keep the hoof moving and help promote natural cleaning.
2. Pick your horse’s feet daily to remove any debris.
3. Have the horse’s frog trimmed to keep the cleft of the frog open to prevent soil and waste impaction.
4. Keep stalls clean and dry.
5. Keep horses out of muddy pastures and paddocks with poor drainage during the raining season.
Treating Thrush
Once your horse is diagnosed with Thrush, there are ways of treating the infection. Treatment can last for 7-14 days.
1. Thoroughly trim the infected tissue. This is probably best done by your farrier or veterinarian.
2. Apply an antibacterial solution daily.
3. Move horse to dry, clean living quarters.
4. In severe cases it you may need to soak or poultice the hoof daily.