What we call the hoof is really the tip of a toe! Made up of a sole (the underside) and a hard wall formed into a thick nail rolled around the tip of the toe. Just like our nails the hoof wall grows continuously and is constantly being worn down by use.
All hoofed animals are called ungulates, and some ungulates, such as sheep, goats, deer, cattle, bison and pigs have two hooves on each foot, which are called a cloven hoof.
Others, such as rhinoceroses and tapirs, have a varying numbers of hooves. The horse and other equids, such as zebra and asses, have only one hoof on each foot.
Over 50 million years ago the horse’s ancestors had four hoofed toes on the front legs and three on the back legs. Over millions of years of evolution the front hooves that we see today were once the third toe and the back hooves were once the second toe on the back legs. (If you would like to know more about the evolution of horses go to ‘From the Beginning.’)
This single hoof on each leg bears all the weight of that limb. For example, a 500kg horse would carry 150kg over each front leg and 100kg over each back leg. Since all this weight is borne by the hoof you can understand how important it is to have healthy, sound hooves. Horse people will always say ‘no hoof, no horse', and that is exactly what can happen if you don't look after a horses hooves.
The most important factors to a good quality, healthy hoof are a well balanced diet, regular (at least every six weeks) visits from a qualified farrier and regular hoof care.
A Balanced Diet
If we don’t have a well balanced, healthy diet we see it in the appearance of our nails, skin and hair. Our fingernails become brittle, flaky and they don't grow very well.
Well, horses are just the same. Their diet and general good health affects the quantity and quality of the hoof (nail) that they grow. A balanced diet is always determined by the individual horse’s current condition, its weight, its breed and what it is being used for.
You have to assess whether your horse is too fat or too thin or just right. When you know how much it weighs, you will be able to weigh out its rations, which are always a percentage of your horse's weight (you wouldn't feed a Shetland the same amount of feed as you would give to a Clydesdale! Likewise, you wouldn't give a pleasure pony the same rations as a Racehorse in full training).
Also, some breeds are more sensitive to diet: for example some pony breeds and Draught breeds cannot eat food that is high in protein and starch (carbohydrates/sugar) without becoming sick.
The most important part of a horse’s diet is roughage (grass and hay). If you are feeding a hard feed, use a pelleted feed from a well-known manufacturer. Follow their instructions and never feed more than they recommend. You should also pick a product that offers a balanced combination of protein, carbohydrates, vitamins and minerals. And try to get a product that includes Biotin (a B complex vitamin), which is very important for healthy hoof growth. (To find out more about feeding horses go to ‘Feed & Pasture')
A Qualified Farrier
A good farrier will make sure that your horses hooves are well balanced and that correct hoof growth is encouraged. He will also help to identify and correct any problems that may occur. (If you would like to see what a farrier does, have a look at the videos at the bottom of this article.)
Remember, he should be a highly trained, specialist craftsman with years of experience. In Australia, good farriers are trained by becoming an apprentice to a qualified farrier and undertake a four-year course at TAFE (Technical College). The apprentice will be trained in anatomy, physiology, locomotion (horse movement) and blacksmithing skills (working with metals).
Be careful when looking for a farrier, as there are many unskilled, untrained people who just buy the equipment and call themselves a farrier. In a single shoeing they can do terrible damage to your horse. You should always be present when the farrier arrives and observe the work that is being done. When a horse has its hooves trimmed you should make sure that they are well shaped, balanced, correctly angled and have a level surface to the ground.
When a horse is shod you should see that the farrier is making the shoe to fit the hoof not the hoof to fit the shoe. Tell the farrier what type of work the horse is doing so that he can use the most appropriate shoe (yes, there is more than one type!). It is also important that you provide a suitable area that is sheltered, flat, clean and dry for the farrier to work.
You should also make sure that your horse is calm by making sure he is used to having his legs picked up and his hooves cleaned out. Do not expect your farrier to train your horse to accept basic hoof care – this is your job. (If you would like to see what a farrier does have a look at the videos on the right).
Some horses, such as native ponies, can be left unshod, however you will need to avoid hard rocky surfaces. Even if your pony is unshod the farrier should still come at least every six weeks to trim and maintain evenness and balance.
If your horse is shod, then - when it is having its winter holiday - it is a good idea to leave it unshod for at least four to six weeks.
Of course, looking at your horse’s hooves should be part of your daily inspection where you check the water supply, make sure the fences are secure and undamaged, your horse does not have any injuries, he is calm and eating well, and he is moving freely and looks bright and alert rather than unhappy and depressed.
When you look at your horse’s hooves you are checking for hoof cracks due to dry conditions, if the shoes are all still well secured (no gaps, no loose nails), and that the bent over ends of the nails (cleats) are sitting down flat. You should also feel around the coronary band and pastern to make sure there are no cuts or skin irritations such as ‘greasy heel'. You should always carry out these inspections in an area where you can see the hoof clearly (not in long grass). If you find a problem, do something about it straight away.
Regular Hoof Care
As well as your daily inspection, you should do your regular hoof care. This may be a weekly job if your horse is out in the paddock or a daily job if he is in a stable or yard and being worked regularly. Your hoof care will involve picking up your horse’s hooves and cleaning out any dirt, manure and anything else that may have become trapped in the sole. Again, check for nails that have become loose, injuries that need treatment and any fungal conditions that may be starting to appear on the skin around the pastern. (See the following common problems: ‘Hoof Abscesses’, ‘Thrush’, ‘Laminitis & Founder’.
In dry conditions, you should paint on a good hoof dressing all over the hoof. These dressings will keep the hoof flexible and stop it from drying out. If the weather conditions are wet and the horse is standing on wet ground, avoid hoof dressings as they will make the hoof too soft and trap excessive moisture inside the hoof.
Remember, you should never inspect a horse or undertake any care or treatment without putting a head collar on the horse and have someone to hold the horse or tie it up.
Points of the Hoof
Wall. The three-layers of wall are a protective shield, covering the sensitive internal hoof tissue. They also help to absorb energy from the hoof hitting the ground as well as providing grip on different surfaces. [more]
The wall has three distinct layers: the pigmented layer, the water layer and the white line. The pigmented layer grows down from the coronary band and is always the same colour as the skin joining the coronet. If the skin is pink the hoof is a whitish colour, if the skin is black then the hoof is black. The water layer grows down from the coronary band as well as the living tissue just inside the walls. It is harder than the pigmented layer and grows thicker as it grows down the hoof. The white line is the inner layer that grows out from the laminar inside the hoof. It is a yellowish colour and quite soft.
Frog. This is a triangular shape which starts about a third of the way down the sole and grows thicker and wider as it meets the heel. It has a central groove that extends up between the heel bulbs. [more]
The frog is made of a dark, rubbery material and it acts as a shock absorber however as the horse moves and puts its hoof to the ground the frog flattens out and then contracts again when the hoof is raised. This mechanical expanding and contracting actually helps pump the blood from the hoof back up to the heart.
Sole. The sole covers the whole area, on the bottom of the hoof, from the white line wall to the frog and bars. Underneath the surface it has a compact, waxy texture and it is called ‘live sole’. [more]
The sole’s surface depends on how much contact it has with the ground. If a horse is shod and the sole is raised from the ground the sole becomes crumbly and can be easily flaked off with a hoofpick. On the other hand if a horse is unshod and the sole is in contact with ground it will become harder with a smooth, bright consistency. The part of the sole at the front of the hoof, which sits under the pedal bone, is called the ‘sole callus’.
Bars. These are inward folds of the wall. They come around at an abrupt angle at the heel. The bars have a three layered structure just like the walls.
When we talk about a horse’s foot we are referring to all the structures right up to the fetlock joint, because all the bones up to this joint were originally the horse’s toe. Only the very last bone (P3) is partially covered by the hard hoof wall. (Look at your own toes and fingers and you will see that your nail only covers the end of the last bone.)
The horse’s toe is made up of three bones: Phalanges/P1, P2, P3. The first bone is called the Long Pastern or P1; the second bone is called the Short Pastern or P2; the last toe bone has several different names: Coffin bone, Pedal Bone, as well as P3. You can pick whichever one you like because they all mean the same bone. The toe also has the small Navicular bone sitting next to the joint of P2 and P3.
Inside the hoof, the Pedal bone (or P3) is connected to the hoof wall by a blood rich fibrous structure called the Laminae. If a horse develops Laminitis or founders, these connecting fibres die and the Pedal bone is no longer attached to the wall (you can find out more about Laminitis in ‘Laminitis & Founder’) .
P3, P2 and the Navicular bone are all connected by a flexor tendon, which acts like a pulley on the foot. Underneath the flexor tendon and the toe bones is the Digital Cushion, which does exactly that – it cushions the bones and tendons from impact.