What are hoof abscesses?
The simplest comparison you could make to define a hoof abscess is that it is like a whitehead pimple. They can be slightly sore or extremely painful with soreness in the area before the pimple even shows up, or sometimes just showing up overnight without warning.
The fastest way to get rid of it is to pop it and let it drain, which is also an instant pain relief as the pressure is relieved. This is the same way an abscess causes pain. They usually start with a localized infection which the body fights against with white blood cells. The infection builds up and expands to create more pressure as the hoof wall can's expand to relieve the pressure like our skin can when we get a pimple.
What causes them?
Most abscesses may become established following a penetrating injury, solar bruising, a nail bind or prick , via the white line or a crack in the hoof wall and begin with bacteria getting into the interior structure of the hoof. This can happen for many reasons including:
- Environmental changes where the hoof shrinks and can crack in dry weather and letting bacteria in those cracks once the weather turns wet.
- Penetration wounds from the horse stepping on something sharp, perforating the sole and letting bacteria in.
- Close nails in a recently shod foot: Nails placed too close into the hoofs sensitive inner structures can let bacteria in and cause an abscess. Even if the nail is removed quickly it creates a pathway into the hoof where bacteria can enter.
- Bruising of the foot occurs most frequently in horses suffering from thin soles and/or collapsed heels. Laminitic horses also suffer from subsolar bruising as the normally concave soles become flatter. Exercise on hard ground increases the problem, but it is wrong to think that bruising is restricted solely to hard ground. Bruising often occurs under really soft, wet conditions in which the foot sinks in the mud onto exposed rock and gravel.
Detecting an abscess and treatment
Clinical signs will depend on the severity of the infection and lameness can vary from minimal lameness to moderate/severe lameness. Other signs might include heat, increased digital pulse, draining tracts with pus and a positive reaction to hoof testers. Similar to pimples , the best treatment is to burst the abscess and let it drain , some will even burst on their own and can burst through the coronary band or heel bulbs as well as the sole. Treatment requires cleaning the foot , establishing drainage using poultice dressings to help draw out infection, keeping the foot wrapped to ensure no further bacteria can get in and sometimes anti-inflammatory and antibiotic medications. Good hoof care all year round is the best line of prevention. Frequent hoof cleaning and routine farrier care with shoes on horses with thin soles prone to bruising and regular trimming are all good things to practice well to help prevent hoof abscesses.