You can help reduce the likely hood of abscesses by being aware of some of the causes.
First some basics:
Hoof abscesses are pockets of pus that form in response to bacterial invasion and proliferation. When pus builds up within the rigid hoof capsule, the pressure on sensitive tissue causes pain(mild to severe). Left untreated, the pus will eventually work its way out, bacterial pressure forces its way out through the path of least resistance. Sometimes a crack or hole forms at the bottom of the horses foot, it often goes through the coronary band, if the abscess is high in the hoof.
Keep in mind that X rays are not always helpful in determining the cause of abscesses. Some foreign bodies cannot be revealed by X rays alone, such as wood.
There are two basic origination points for abscesses, internal and external.
With an external source, a foreign body, such as a nail can causes a breach/puncture in the hoof leading to an abscess. Sometimes bacteria gain access to the hoof from the environment, through minute cracks or breaches of the capsule that aren’t evident to casual observation. These breaches might not be visually apparent but consider; a tiny breach might have occurred and resealed itself before you observed it.
If external causes have been ruled out, then it is likely that there was/is an internal cause. Internal causes of abscess are the result of bacterial build up because of separation, or damage to the internal structures of the hoof. Structural alterations/injuries (such as rotation of the pedal bone) can cause damage and infection to the sensitive tissues of the hoof.
These are some of the factors that can contribute to or cause internal abscessing:
- If a horse is grossly overweight, and/or has had a laminitic episode.
- Poor trimming. Poor foot conformation.
- Bad horn quality(creates cracks and breaches)
- Age (some older horses tend to abscess more)
- Severe Concussion e.g., road founder
A vicious cycle may ensue when; you have a few of these things coinciding. If you have any (or a combination of) of these problems, they can cause the horses feet to crack or disintegrate further- causing more stress on the internal structures. When more stress is placed on the internal structures of the hoof than normal…trauma/damage may result in the pedal bone displacing (founder).
When the pedal bone displaces, the trauma allows bacteria in the foot to proliferate, resulting in an abscess. In those circumstances (If there’s no sign of an entry wound) It is not advisable to invade the foot by probing round (with a hoof knife) to find where the abscess is, as that in itself is likely to increase the risk of infection and just cause further problems.
It is in these situations, an x ray is helpful and advisable, to see what is going wrong.
Now we can get into why some horses abscess frequently:
Ordinarily, when a horse has recurring abscesses’ that’s not the case. It’s usually because the original abscess was not sufficiently drained, and the pus built up again over time.
If the original drainage hole was not big enough, it may have resealed before all the pus escaped. An abscess can also form several pockets within the hoof. Unless each chamber is drained, the abscess will form again. If there is a foreign body in the hoof capsule that has not been identified, and removed, it will create infections and abscess repeatedly.
If your horse abscesses regularly, and the cause eludes you; it could be that the combination of these things, is the cause: Poor trimming, poor foot conformation, bad horn quality or severe concussion, with environmental factors such as rocks/sticks in wet, dirty, paddocks. You can help reduce the likely hood of abscesses by being aware of some the causes. Having a good environment, with proper hoof-care, will help the foot retain its integrity, reducing opportunity for abscesses.