Understanding hoof physiology

Understanding hoof physiology

You can learn a lot about your horse’s health and background just by looking at his hoof physiology.

Can you really learn about your horse’s health history by looking at his feet? To find out, let’s go back to the beginning. Most hoof care professionals agree that hoof physiology has not changed for thousands of years. When a foal is born, the hoof soles are made up of fleshy tentacles called perionychium. The purpose of the perionychium is to protect the mare while the foal is in the womb, and allow smooth entry into the birth canal and out of the mare. Within hours, the perionychium dry up and the hoof becomes harder and ready to negotiate the tough terrain ahead.

From the beginning

foal's hoof
Foal’s hoof

When we look closely at the hoof physiology of a foal, we see it has the same shape and design as a grown horse. It’s just smaller. There are some subtle differences, however. The laminae connection is tighter, is the same around the entire hoof, and grows at a much faster rate. Until adulthood, the laminae grow down from the coronet band as well as in circumference, and looks similar to wild horses’ hooves. It’s because of this tightly connected laminae that the internal structures, coffin bone and navicular bone are well up inside the hoof capsule with the extensor process of the coffin bone in line with the coronet band (hairline). The outer hoof capsule is smooth and grows straight from the coronet band. The sole is naturally concaved since the coffin bone is sitting high in the hoof capsule where it belongs.

If the foal was to be raised in his natural wild environment, this tight connection with natural concavity would remain. In addition, when the foal is born, the digital cushion in the back of the hoof is a fatty tissue. If he is allowed to move the way nature intended, this fatty tissue turns to a dense and well developed fibrocartilage. The influences of domestication are what most often negatively alter the perfect hoof that nature gives the newborn foal.

The environmental factor

Environment plays a huge role in hoof physiology, and the changes that may occur to it. Diet, nutrition, lifestyle, toxic insults like grains, chemical wormers and vaccines, trimming styles, changes in temperature and lack of movement all impact the integrity between the connection of the laminae. Over time, the constant bombardment of toxic influences take their toll on the hoof, altering it from its originally health state.

The hoof in the image below has quite the history. It belongs to a jumper, aged nine, who competed in shoes all her life and was fed large amounts of grain. After she came up lame, she was placed in a stall for a year with corrective shoes, but the lameness did not resolve. The hoof is tattered, flat and contracted, with underrun heels and chronic white line disease. This horse was what we call a “high/low” — one front hoof had a much higher angle and the other was flat. Placed in a natural hoof care program and trimmed to the wild horse model, she achieved soundness in three weeks.

jumper hoof
Hoof belonging to a jumper (aged 9).

The effects of infection

Natural hoof care practitioners will often be called in on a chronically lame horse, only to find that the central sulcus in the back of the frog is deep and full of infection. Upon making some changes to the horse’s diet, lifestyle and trim style, the infection will clear up, allowing the horse to begin using the back of the hoof and return readily to soundness.

Thanks to years of not engaging the back of the foot, these poor horses have been landing toe first, forcing their heels to contract from lack of use and trapping bacteria in the central sulcus. Over time, this improper locomotion may lead to changes in the navicular region and bone.

hoof toe first landing
Hoof from landing toe first.

This image shows the effects of landing toe first. Contracted heels and an atrophied frog are a result of not using the caudal hoof. The correct way for the horse to land is heel first. That way, the hoof spreads open, filling with blood and nourishing the microscopic blood vessels. When locomotion is correct, the impact caused from landing is diffused through blood flow into the hoof.

The use of boots with pads, along with diet changes, can be hugely beneficial in getting the horse to begin using the back of the foot, thereby bringing the necessary healing blood flow back into the foot and restoring soundness.

If we look closely, the horse’s hoof physiology will give us a clear picture, from several angles, as to what has been happening in his life.