Treating hoof abscesses

Q: I wonder if your experts can give me some help and advice about ideally preventing but also treating hoof abscesses/stone bruises.

There is a lot of conflicting information out there. For starters, I don’t really understand why an infection is caused by an external injury such as a stone bruise.

Is it best to take the shoe off, have the vet or farrier dig a drainage hole, and using tubbing/poultices, or let nature take its course?

And why, after many trouble-free winters, am I having such a terrible time of multiple abscesses with my horse at the present?

He is paddocked during the day and stabled overnight. He is a thoroughbred, but has fairly good feet – though I have noticed his soles are very ‘pitted’ at present, and they are very flexible/indent easily when I push them with my thumb. What causes this and is it connected to the abscess problem?

And finally, is there something in his diet I can or should be addressing?

Tania, Auckland

A: Thanks for your question. The most common cause of abscesses is when something foreign enters the foot. For example, grit or gravel that works its way through the white line or sole and becomes trapped in the hoof. The horses’ body reacts accordingly and an abscess usually forms as the beginning of the process to flush the debris out of the body.

If a shoe has been fitted then it’s common practice for this to be removed before any treatment begins. Depending on where it has occurred, draining abscesses can be easier at the white line if at all possible as this is a relatively softer, easier to get to and when done correctly, any drainage holes will cause less of a problem. Shoes are usually fitted covering the white line so removing this will be a good start.

In most cases, the vet or farrier will use hoof testers to precisely locate the problem area of the hoof by using the testers to apply direct pressure on various parts of the sole, frog and hoof wall. We rely on the horse to indicate the most painful area by his reaction which usually starts with a raising of the head when we get closer to the pain. At the same time, we will look for the potential entry point of the offending debris. Removing as little hoof as required with a sharp hoof knife, a drainage hole is made and if it’s successful, some pus is seen which will usually be black and pungent.

Completely draining the abscess is vital and this is usually something the owner will take over. There are numerous methods of drawing out abscesses and people have their own views on what works best.

A commonly adopted method is to hot tub the foot in an Epsom salt solution and then apply a veterinary poultice dressing – Animalintex is a brand widely available, easy to use and works well. To keep the poultice in place, bandaging the hoof with vetwrap then duct tape is effective and allows the poultice to be changed at least every 12 hours. Using a nappy over the poultice is also a good way to keep the poultice in place.

Many horse vets prefer not to administer antibiotics for hoof abscesses – preferring the hoof be drained externally with a poultice as this arguably delivers better results. Letting nature run its course isn’t a recommended approach alone – the abscess is likely to get worse and become more painful for the horse if left untreated.

Each time the dressing is changed, there could be some pus on the poultice. Making sure the abscess is completely drained is vital – too many times owners are in a rush to put the shoe back on which can cause any remaining abscess to become trapped in the hoof and return again.

We usually see these sorts of problems more often in the wet seasons when the hoof is softer and debris can more easily enter the hoof. From what you’ve told me, it sounds like your horse has thin soles (as you say you can quite easily move them with your thumb). The pitting will be from the wet conditions and the environment in the paddock all exacerbated by the fact he is a thoroughbred which traditionally have thinner soles than some other horses. I’d suggest this combination is most likely to be contributing to your regular abscesses this season.

My advice to reduce the likelihood of the problem in your case is to move the horse to a more suitable environment. Alternatively, protecting the soles for a short period may give them a chance to recover.

A hoof supplement can often help to improve the quality of the horn that is produced but using one of the better quality supplements is vital if you want to see any visible improvements in the hoof and sole.

Talking to your vet about tetanus shots being up to date is also recommended.

David Hankin Dip.WCF

This question and answer first appeared in NZ Horse & Pony magazine August 2011