Research has shown that hoof wall growth was 50% higher in growing ponies that had a positive energy balance than in ponies on a restricted diet with a reduced body growth rate. It is a common observation that when horses gain weight on lush spring grass, they also grow hooves faster. Recent research has shown that increasing dietary fat intake has little effect on growth rate or hoof strength, but fat can be a valuable addition to the diet in the role of maintaining a positive energy balance.

In addition to energy, a well-balanced diet will provide the nutrients the horse needs for overall health and well-being, and these will in turn help fuel healthy hoof growth. The hoof wall is about 93% protein on a dry matter basis, and high-quality dietary protein will provide the horse with the amino acids researchers have theorized to be essential for hoof growth. Due to the composition of the hoof wall, most commercially available hoof supplements contain methionine.

However, methionine is only one of the amino acids in hoof protein, and deficiencies of any essential amino acid can be as detrimental as a methionine deficiency. The hoof contains high levels of cystine, arginine, leucine, lysine, proline, serine, glycine, and valine, and lower levels of methionine, phenylalanine, and histidine. When the researchers compared the amino acid content of a normal hoof and a poor quality horn, they found a linear correlation between cystine content and hardness in a normal horn, but not in a poor horn. quality. Normal horn protein contained higher levels of threonine, phenylalanine and proline and lower levels of arginine than poor quality horn.

Further research has shown that there is a clear difference between the distribution of two sulfur amino acids in the keratinizing epidermis of the hoof. Cystine was mainly localized in the keratinocytes of the keratogenic zone of the matrix and in the nucleated keratinocytes which formed the incompletely keratinized basal part of the primary epidermal laminae and covered the lateral surface of the fully keratinized outer part of these laminae. Methionine was localized mainly in the basal layer and in the spinous layer of the matrix and in the secondary epidermal laminae of the laminar layer. The pathway that converts methionine to cysteine ​​is believed to be imperative in the production of a quality hoof.

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Diets deficient in protein lead to reduced hoof growth and hoof cracking and cracking, but diets intended to promote faster growth in young horses have been shown to not necessarily maximize hoof growth. This suggests that the amino acid requirements for general body growth and faster hoof growth are different, and scientists have studied this difference in search of which nutrients are most important for producing better hooves.

Most of the research focus on hoof growth and hoof wall quality has involved biotin. The normal horse is thought to have a biotin requirement of 1–2 mg per day, and this can be supplied in certain feeds as a component of commercial vitamin and mineral premixes or by intestinal synthesis by microorganisms in the large intestine . Biotin is a cofactor in a number of enzyme systems.

In other animals, chronic biotin deficiencies lead to damage to the skin and other keratinized structures, and supplemental biotin was first used in pigs to treat hoof problems. Studies have shown that supplemental biotin at levels of 15-20 mg per day has positive effects on hoof quality in some horses, but does not help all horses.

A German study on the long-term influence of dietary biotin in horses with a brittle hoof horn and chipped hooves was conducted over periods ranging from one to six years. Ninety-seven horses received 5 mg of biotin per 220 to 330 pounds of body weight per day; 11 horses were not supplemented with biotin and served as controls. The hooves of all horses were assessed macroscopically every three to four months, and horn specimens from the proximal wall were histologically and physically examined in 25 horses. The hoof horn condition of biotin-supplemented horses improved after eight to 15 months of supplementation, while the hoof horn condition of most control horses remained constant throughout the treatment period. study. Hoof horn condition deteriorated in seven of 10 horses after biotin supplementation was reduced or stopped. The horn growth rate of treated and control horses was the same.

Biotin only enhances the growth of the new hoof horn, not the existing hoof, so its effectiveness depends on reliable administration at recommended levels. For this reason, several weeks may pass before a noticeable difference exists in the growth of new hooves near the coronal band. It should be noted that some horses respond more positively to biotin supplementation than others. Just because biotin supplementation doesn’t improve one horse’s hooves doesn’t mean it won’t help the next horse’s hooves.

Obviously, nutrition is important in producing strong, healthy hooves. Basic hoof care is almost as important. A regular program of hoof trimming for barefoot horses and trimming/readjustment for shod horses should be followed. Farrier care every four to six weeks is sufficient for most horses. Letting horses go longer than about six weeks without trimming is problematic, as longer hooves tend to chip and split. Even if the hooves are not very overgrown, a slight trimming and smoothing can sometimes prevent the progression of small cracks. While many inactive, little-used horses can walk barefoot, shoeing protects the hoof and prevents excessive wear and tear on hooves that tend to chip and crack. The farrier should not file or rasp the shiny outer coating of the hoof, as this hard layer of horn helps retain needed moisture in the hoof.

Hoof dressings are often touted as the cure for poor hoof condition, especially for horses that have dry, chipped hooves. Research has been done to find out if the use of dressings has an impact, good or bad, on the hoof. A study conducted at the University of Edinburgh looked at the passage of moisture in and out of the hoof capsule. The researchers tested full-thickness samples of wall, sole and frog tissue obtained from equine cadavers. The samples were taken from hooves in good condition (solid, without cracks) and in poor condition (cracks visible). In samples of undamaged hooves, moisture penetrated less than one millimeter into any tissue. Poor condition hoof samples allowed much greater penetration of moisture into and through the internal hoof tissues. These results indicate that there is a natural moisture barrier in healthy hoof tissue, and products claiming to moisturize the hoof can be expected to provide little benefit to healthy hooves.

The ingredients in some hoof dressings can actually be harmful, overdrying the outer layers of the hoof and leading to brittle tissue that can easily develop small cracks. Formalin, solvents or tar-based products are ingredients that can damage the outer layers of the hoof horn. Such damage allows moisture to enter and exit the hoof more freely than in hooves with a healthy outer horn. Lower strength has been measured in hoof fabric that is either too dry or too wet, so altering the natural moisture level is not considered beneficial. Additionally, dirt and bacteria can enter the cracks, eventually causing infection.

To sum up hoof management, remember that good basic nutrition is the key to hoof quality. Use a feed designed for the class of horse you are feeding and feed it according to the manufacturer’s instructions and the desired body condition. Look for foods that are balanced for macro and microminerals. Commercial foods should not be cut with oats, as this distorts the nutritional balance.

If everything is done from a nutritional and farrier point of view and the quality of the hooves is still poor, it is worth experimenting with biotin, methionine and zinc supplements. Kentucky Equine Research recommends the use of Bio-Bloom PS, a dual action supplement designed to promote and maintain healthy hooves and skin from within.

Unfortunately there is no quick fix and maintaining good footing on a horse is the combined result of good farriery, good nutrition, good health care and selecting horses that genetically have healthy hooves.

Reprinted with kind permission from Kentucky Equine Research. Visit ker.com for the latest in equine nutrition and management, and subscribe to Equinews to receive these articles directly.