Care and Management
of the Hoof Capsule
Exercise is an extremely important factor in the health of the hoof and the horse in general. The absence of muscles below the knee and hock require compression of the venous plexi in the hoof to return blood back up the leg. Without exercise blood circulation is slow and inefficient and delivery of the vital components for hoof health can be impaired.
The hoof capsule is a hornified cornified epithelium with a requirement for sulfur bearing amino acids. Good quality feeds are necessary for good strength and growth rate. Lysine, cystine and methionine are the critical amino acids for the strengthening disulfide bonds in the keratinized cells. These amino acids are found in good quantity in feeds based on milk or soybean protein. Gelatin is not rich in these amino acids and probably only plays a role in the sparing of the essential amino acids in the diet. Biotin is only a cofactor vitamin that assembles the amino acids. Diets low in the essential amino acids will show a very poor response to biotin supplementation. Trace minerals and micronutrients are also a vitally important factor in the health of the hoof. Supplementation of these is important in that most of the diets of our domestic animals are produced in a region that is not likely to have the variety of sources of these nutrients. Kelp has been shown to be a very effective supplement to provide these micronutrients. Probiotics are also very effective in promoting good hoof growth. They act on the gut flora to enhance digestion and absorption of the nutrients in the feed making more efficient use of the nutrients. Also the microflora produce biotin which is a natural source for this vitamin.
Horses that are stall bound suffer the most insults to the hoof capsule. The environment the hoof is in is quite different than what is encountered just a few inches up. The bedding is s source of harmful ammonia, which attacks the hoof and destroys the quality of the protein in the hoof by breaking down the bonds in the keratinized protein. The hoof, from the feces and urine in the bedding absorbs excessive moisture. Fungus and bacteria thrive in the bedding and attack the hoof.
It has been my experience that the incidence of fungus infections in the wall is much lower in pasture horses than stall bound horses. Excessively wet conditions are damaging to the hoof. The keratinized protein has a soluble phospholipid "glue" that is leached out. The cells swell with the osmotic pressure of the water and break the intercellular bonds. These bonds cannot be reformed, as the cells are no longer alive and capable of repair.
Many problems have been associated with excessively dry conditions such as cracks and contracted feet. It is my experience that aside from extremely difficult trimming and bruising from concussion on the hard ground there are no great ill effects from a foot that is dry. The hardness of the foot is necessary to withstand the conditions of the hard ground. It is not unlike calluses on our hands in response to hard work. Contraction of the hoof is a symptom related to a problem in the hoof or leg. Atrophy occurs when hoof is not fully loaded. Without proper stimulation the hoof contracts as a result of the change in weight bearing. There are normal variations of the hoof size throughout the year due to the content of water in the hoof. Wetter seasons are going to cause the hoof to swell and this could possibly lead the horse to require a larger shoe. This is not necessarily a problem if the hoof remains reasonably healthy in the other respects.
Poor Shoeing Techniques
The largest problem with foot care is the removal of the wall unnecessarily. The
reasons for this practice are numerous and most of the time is damaging to the hoof.
Improving the appearance, "backing the toe up" or compensating for the lack of skill
in fitting the shoe to the hoof are a few of the reasons the wall is removed. I am
not advocating the wall should never be rasped on the outside but it should be undertaken
with the greatest care and consideration of what is the benefit to the animal. Shoe
design is another factor in the removal of the wall. Nail placement in the shoe sometimes
makes it impossible to place the shoe securely and have a cosmetically good-
Poor Shoe Design
Horseshoe design greatly affects the hoof. The primary factors negatively impacting the hoof are the nail set in the shoe and the width of the web. If the nails are punched too fine, a common problem seen on many racing and training type plates, this may lead to all sorts of related problems. Because of design and fit issues, the farrier, in trying to present a neat job. usually has to rasp the wall back to the shoe. This ultimately leads to removing enough wall to weaken the hoof. Also the narrow web shoe design does not usually provide enough coverage of the sole to prevent pathologies resulting from the bruising and concussion that can occur. Many of these shoes are widely used because they are relatively easy to shape cold.
Owner Related Problems
Owners can and do create their own problems by trying to fix something that isn’t broken. This is primarily related to the excessive use of greasy hoof conditioners. In the desire to do the right thing the hoof becomes so saturated with softeners that the wall can no longer function. Splitting and peeling is misinterpreted as dryness and more conditioner is applied until the shoes no longer stay on and the foot is peeling because the wall is saturated with greasy softeners. The only remedy for this is to stop the greasy hoof preparations and grow out a new hoof. There are no fat secreting glands in the hoof and it is not a normal constituent of the wall. Flexibility of the hoof is restored by moisture, and care must be taken not to over saturate the hoof so it is unable to cope with a tough environment. Topical preparations that are sealants may be detrimental because they block transpiration of moisture and exclude oxygen, which creates an environment favorable to anaerobic organisms to attack the wall. There are products that don’t block the normal "breathing" of the wall, protect from the harmful effects of ammonia and condition the keratinized protein to be more resilient without the use of grease. These have been shown to be beneficial in retaining the health of the hoof.