The decision to shoe or not is one that is based on an evaluation of three main concerns. The first being the quality of health of the horse’s hoof (i.e. the presence of any deep cracks or extreme distortions of the wall). The second being a noticeable weakness in the limb-to-hoof connection, resulting in a lack of weightbearing capacity for the horse (i.e. Collapsed "urderran" heels, Longtoe / Lowheel syndrome, Club footedness, etc.). And last, the consideration of the workload. Certain jobs the horse may be asked to perform may require a particular type of shoe. For instance, a Trail horse will need traction for those slippery spots, whereas a Reining horse that moves quickly and slides will need a non-traction type shoe. We will discuss the various types of traction and their purpose a little later.

Seeing the Signs of Stress

When observing your horse’s feet there are some general notes on anatomy you must be aware of.

The single most important point is that you should realize that your horse’s hooves are a result of a metabolic process in his body. This process is no different from your nail growth. Diet and the type of exercise your horse faces has a direct affect on the growth process of the body’s horn producing times. If you or your horse become ill some signs of bodily stress can be noticed. For example, the skin, hair and horn will become dull in appearance and in extreme cases these tissues may deteriorate and "slough-off". It has been said that the horse’s feet are its barometer and, as good horse owners, we should learn how to read it. Let’s begin by defining what kind of stress can take place. Generally speaking there are two: metabolic and mechanical.

1. Metabolic Stress – This is defined as any change to the horse’s external appearance due to an internal factor. This can range from a slight raise in the horse’s body temperature to a severe allergic reaction. In each of these cases, a minor case will produce a superficial "ripple" or ring on the outer hoof wall, whereas a major case will result in a total hoof wall deformity (deep ridges, dished-out walls, etc.). Such metabolic stresses are not easily detected in their earliest stages.

   And for this very reason, such problems as Laminitis, Navicular syndrome and Pedal Osteitis can be at an acute (advanced and life threatening) level by the time any actual structural changes in the horse’s hooves are noticed. Many unanswered questions about the metabolic process of horses and humans still remain an enigma. In recent years, however, practitioners of modern medical research have benefited from the marvels of new and improved diagnostic equipment. Along with Radiology (images of bone) and Ultrasonography (images of soft tissues) the advent of a highly sensitive heat detection instrument called the Infrared Thermograph has made it possible to detect bodily stress at a much earlier stage.

   In a book, The Illustrated Atlas of Clinical Equine Anatomy and Common Disorders of the Horse, veterinarian Ronald J. Riegel writes:
   

   Thermography in the equine practice is being used more frequently as a diagnostic aid in lameness evaluation. Inflammatory processes can be identified weeks earlier than with normal routine clinical evaluations. He then goes on to say, It [Thermography] is not a replacement for radiological or ultrasonic studies, but it can be an enhancement.

2. On an everyday level the stress that you and I can observe is not of a metabolic type but that of a simpler, mechanical form. The horse’s feet should always have certain characteristics, if they are not present the hoof is said to be under a mechanical stress.

   1. the external wall should be hard and, if healthy, should have a shine or "varnish" that acts to repel the weather and the elements that the horse’s hoof comes in contact with.
   2. the sole should be hard as well as "arched." A flat-soled horse will bruise easily and may require some protection.
   3. the frog and bulbs must have elasticity. This means it must be a little softer and pliable. It has been said that the horse has five hearts – one in his chest and hour on the ground. It is important to mention that the frog must be flexible and expandable in relation to a healthy wall and sole in order to absorb shock. There is a myth that suggests that the frog must actually bear the weight of the horse and concuss (hit the ground first) in order to pump blood through the hoof.
   
   If a frog happens to make contact with the ground before its counterpart, due to the conformation of the hoof, and the wall and sole are healthy, then so be it. If, however, a healthy wall and sole were to be cut down to force the frog to the ground this will actually result in an inflammatory stress that will only serve to give the horse pain.

   Conditions that may contribute to mechanical stress are:
   

   • Hoof walls that are left untrimmed – The unbalanced hoof will appear either in the form of "Dishing" (a concave, inward wall) or "bullnosing" (convex, outward wall).
   • Extreme climates / Too wet or too dry – Hooves will develop vertical cracks. Minor cracks are often referred to as "sandcracks." They do not penetrate the whiteline or extend up into the coronary area of the foot.
   • Traumatic injury to the hoof wall / bruising – Generally, a blow to the coronary area will become evident a few weeks afterwards. Not unlike receiving a hit on your fingernail from a hammer. Red discoloration will appear and a horizontal crack may eventually form where the horn tissue has been damaged.
   • Traumatic injury to the sole / bruising – As in the above scenario, red discoloration may appear. This is a result of a subcutaneous (below the skin surface) bleeding of damaged tissue.
   • Puncture wound / abscess – Any foreign object that is lodged into the sensitive tissues of the hoof will "fester" or build-up puss in and around the point of the injury.
   • Friction-related injuries – This relates to any irritation that results from a constant rubbing of a tissue by another object. The simplest example of this is relative to you having a pebble in your boot or if your boots were too small for your feet. The pain created can be unbearable. This is essentially what can happen to your horse. A stone wedged between his foot and his shoe can be painful if left for a long period of time. Also, it could be that a horse was fitted with an improper size shoe. If the shoe is too short and does not provide good heel protection the edge of the shoe could cause extreme sole pressure.

Conclusion

In closing, I think Dr. John P. Hughes, contributing author of University of California-Davis Book of Horses, summarized it best by stressing the importance of understanding our horses. He writes:

Often quoted was the old Arabian proverb – The outside of the horse is good for the inside of a man. This is probably even more true today.

Resources:

• The Principle of Horseshoeing II, Dr. Doug Butler, Laporte, CO.
• Illustrated Atlas of Clinical Equine Anatomy and Common Disorders of the Horse, Ronald J. Riegel DVM, Marysville, OH.
• Book of Horses, University of California-Davis.

© 2000 Bryan Farcus. All rights reserved. Bryan Farcus, certified farrier and head of the Department of Farrier Science at Meredith Manor International Equestrian Centre, has been combining the skills of horseshoeing, teaching and riding for the past ten years. He has also achieved a BS in Business Management. Bryan is the creator of "Farrier-Friendly"™ articles and products aimed at improving the general understanding of horseshoeing through horsemanship. For a complete collection of "Farrier-Friendly"™ articles click here.