Hoofcare

You’ll have heard the old adage “No hoof, no horse”. It’s especially true when it comes to diseases of the lymphatic and circulatory system in the lower legs. I want to be clear that when I reference shoes or shod horses in this article, I mean steel shoes. We should look into alternative shoeing techniques such as hoof boots and flexible composite options.

It is probably important to make clear at this stage that this is absolutely not an anti-farrier article. If your farrier can shoe your CPL horse in a way that minimises the risks discussed below and optimises circulation and hoof health, that is wonderful. Likewise, many farriers are also excellent barefoot trimmers and have lots of happy healthy clients, both shod and barefoot. But we do need to consider some things about the more traditional shoeing methods…

The lymphatic system is considered both a part of the immune and circulatory systems – what we know about the lymphatics in the lower leg is that they rely almost entirely on healthy circulation and a pump action (“lymphatic retraction”) which is promoted by the flexion of the fetlock joint and hoof. Inside the hoof are the venous plexus – large groups of blood vessels that are squeezed into action by the digital cushion (internally, they sit above the frog and around the heel), hoof walls and the coffin bone. This pumps the blood up and out of the hoof and leg, back to the heart. The lymph vessels are subject to the same flexion. Healthy circulation in this area goes a long way towards improving lymphatic drainage. Think of it as though the lymph is “hitching a ride” on the circulatory system. There is a good motion graphic about halfway down this page that demonstrates the hoof flexing.

Looking at barefoot horses, we can see that circulation is improved by 1) a large, healthy frog which when in contact with the ground helps both protect and activate the plantar cushion; 2) by allowing the hoof its natural ability to flex and dissipate concussion, which is significantly reduced when shod; and 3) the angle of the coffin bone to support the internal structures. Unshod, the hoof wall is naturally flexible, which helps to squeeze and release the venous plexus when it flexes to absorb concussion.

When the hoof is raised, the veins open and blood flows back up the leg, along with lymph. When the hoof is down, the vessels are compressed. This helps us to understand why stabling horses with compromised lymphatics or lymphatic disease, prevents the natural flow of blood and lymph back to the heart and lymph nodes respectively.

Read The Blood Pumping Mechanism of the Hoof by Dr Craig Wood.

Sometimes people say “my horse can’t go barefoot because he has terrible hoof walls”. But what if nailing something into the wall will only further compromise the structure? As the hoof chips away more, the nails have to go in tighter each time which can cause the tissue around the nail holes to die, presenting as black discolouration in the wall around the holes and providing entry points for bacteria into the white line. Another common concern is that the hooves will wear down “too quickly”. Infact, the hoof growth is stimulated by contact with the ground and will in most cases respond well to exercise as the circulation improves, including road work. The hooves won’t wear down to stumps – the more use they get, the better they grow… As long as the horse has a healthy, well balanced diet. Varied terrain is perfect for conditioning hooves, although some horses who have had previous hoof problems resulting in very thin soles or bone/sole remodelling may need the additional support of boots when covering rocky terrain.

Diet plays the greatest role of all in good hoof quality. Given that horses with CPL tend to have poorer hoof quality, a barefoot-friendly diet is essential to keeping them sound. Both Pete Ramey and Prof. Chris Pollitt have written extensively on diet balancing for better hoof quality.

Clinical anatomy and physiology of the normal equine foot is an interesting read.

Something to consider is the increased effect of concussion when shod because these CPL horses are often chronic stampers. Even when they don’t have feather mites, their legs can feel strange and uncomfortable at times as they fill and fibrosis forms. The horses stamp their feet rapidly and with incredible power, sometimes smashing holes into the ground. This can cause concussive bone changes such as ringbone, sidebone, hock and knee arthritis which poses us two problems when the horse has CPL. Firstly, they may require injections which as we know, are contraindicated. Secondly, if we need to apply compression to the legs, the horse is less likely to tolerate the discomfort of bandaging over the bone changes. Unfortunately, that typically means we can’t compress the legs in the event that the horse has to be stabled or needs Combined Decongestive Therapy.

Ergots and chestnuts can become distorted, growing oddly, splitting and twisting and this can let infection in so they must also be trimmed regularly.

Now we also know that CPL can affect the quality of the hoof and cause chronic and treatment resistant thrush. This can be helped or even prevented by providing a healthy barefoot diet. Some shod horses have very contracted heels, where the heel bulbs are pushed tightly together and the deep crevice that forms increases the risk of thrush. Shoes can also affect proprioception which alters the hoof load and the horse’s ability to feel the ground and that can potentially lead to bone, tendon and ligament injury. Being on box rest is something we would really like to avoid for the CPL horse.

Research into CPL in draft horses has shown that they can be prone to developing laminitis. It could be that this is a result of the chronic inflammation but it could also be because many CPL cases come about as a result of neglect in horses who are genetically predisposed. So it is really important that you and your hoofcare provider keep an eye out for symptoms and soreness in the feet and that your horse doesn’t become overweight. You can learn more about laminitis here.

Mark Johnson is actually looking into P3 descent in CPL horses so if you happen to have any appropriate xrays he may be interested in seeing them.

While there are some exceptionally good, knowledgeable farriers and barefoot trimmers, there are also really bad versions of both out there. Do your research when you are looking for a farrier or trimmer and make sure to employ someone with a good reputation who can talk you through what they will be doing and will be reliable and thorough in their work. It is super important that the hoofcare provider you choose understands that CPL horses operate at a level of discomfort in the legs unlike healthy horses so in a similar way to laminitics will likely need plenty of breaks to put their feet down or may not have enough flexion to lift them up very high. Don’t forget that when they’re standing still, their legs are filling (and not draining effectively) so they logically want to avoid doing this where possible. Let them move around between trimming each hoof.

You can source hoof boots and fitting kits from Urban Horse and Hoof Bootique.