Essential Nutrition for Hoof Health

Biotin is a water-soluble B vitamin that is commonly recognised as being beneficial for horses with poor hooves. Like other B vitamins, biotin is produced by the micro-organisms that live in the horse’s hind gut as they break down fibre.

When plenty of fibre is fed, a healthy population of micro-organisms can usually provide sufficient biotin to meet the basic requirements of horses and ponies. Poor-quality hooves can therefore be indicative of an unhealthy digestive system, which might occur as a result of restricted fibre intake. This is most common in performance horses and sometimes good doers so it is really important to maximise fibre intake in these individuals by choosing the most appropriate type of forage for them.

Several research studies have been conducted to identify the level of horse biotin supplement that can help to address poor hoof horn growth. One study found that supplementation with 15mg of biotin per day over a 10 month period achieved increased hoof hardness and greater growth rates than horses supplemented with 7.5mg per day (Buffa et al, 1992), whereas another study found that continuous supplementation with biotin at 20mg per day over a 3 year period reduced the severity of hoof horn defects, increased tensile strength and improved the condition of the white line (Josseck et al, 1995). This information suggest that between 15 and 20mg of biotin horse supplement per day should help to generate healthy hooves.

Zinc is involved in the health and integrity of hair, skin and hoof. Hooves require zinc for the prevention of defective keratin, the tough material found in the outer layers of hoof and skin. If keratin is not properly formed, the hoof will be soft and brittle.

Research carried out by Coenen (1997) found that horses with insufficient hoof horn strength had less zinc in the hoof horn and plasma than horses with no hoof horn damage.

The form in which zinc is added to feeds and supplements could impact on the quality of your horse’s hooves. Zinc is a trace mineral, which is vulnerable to interactions with other minerals in the digestive system when in an inorganic form. Chelated zinc is an organic form of the mineral, which is achieved by attaching it to a peptide or amino acid. This process improves the absorption of the zinc, so tends to result in better health and condition of tissues such as hooves.

It can be tempting to think ‘the more the merrier’, when feeding nutrients to promote equine hoof health. However, there are many circumstances where minerals compete for the same transport mechanisms and these mineral interactions mean that if one mineral is fed at a significantly higher level it may result in a deficiency of another. Zinc and copper are two minerals that compete for the same binding site and feeding significantly higher amounts of zinc can result in a deficiency of copper. Based on the requirements set out in the Nutrient Requirements of Horses (2007) meeting the requirements for zinc and copper results in a ratio of 4 parts zinc to 1 part copper.

Calcium is a mineral essential for proper bone development, but it is also required for cell-to-cell attachment in the hoof horn. Calcium is linked very closely to phosphorus and the ratio of these two minerals in the diet is also crucial – ideally, a 2:1 calcium to phosphorous ratio should exist.

In a study conducted at the Royal Dick Vet School by Dr Sue Kempson (1987), two different problems with hoof horn were identified. The first was described as a lack of horn in the outer layers and showed improvement when biotin was added to the horse’s diet. The second, described as lack of good keratin attachment, improved only when calcium intake was increased alongside the biotin. In this study, the calcium was increased by adding in alfalfa, which is a naturally abundant source of highly available calcium.

The most common reason for diets being low in calcium is when high levels of straight cereals like oats are fed which are high in phosphorus. Linseed which is commonly added to horses rations as a straight also has an inverse calcium to phosphorus ration. Adding alfalfa when feeding straights is an easy way to help create a better calcium-to-phosphorus ratio. A 1:1 ratio of alfalfa to linseed or oats by weight helps to produce a 2:1 ratio in the bucket feed.

Whilst evidence from research is lacking, methionine is another nutrient regularly recommended for improving hoof quality based on its dietary role. Methionine is a sulphur containing essential amino acid and a major structural component of proteins and enzymes in the body. Keratin is made up of many proteins and contains the essential amino acid methionine. It therefore stands to reason that a low intake of methionine would impact equine hoof health and quality.

The methionine requirement has yet to be determined in the horse. Generally, it is assumed that if horse’s overall protein and energy requirements are met, including for lysine which is the one essential amino acid that requirements for the horse are known, that the horse’s intake of other essential amino acids will be adequate.

The horse’s natural source of essential amino acids is forage which can offer variable levels; for example alfalfa is a relatively abundant source of lysine and methionine compared to grass as it is a legume and therefore able to fix nitrogen from the environment which it converts into protein which it incorporates into its own tissue.

Horses and ponies that are most likely to miss out on essential amino acids including methionine are those that are on restricted diets for weight management reasons.  Restricted grass access, lower forage intakes, the inclusion of straw in the diet, and soaked forages can all contribute to a sub-optimal intake of essential amino acids which can be addressed by the addition of a high specification feed balancer alongside the forage ration.

MSM is another commonly used source of bio-available sulphur in hoof supplements for horses. MSM is naturally occurring in animals and plants but, like many ingredients, is manufactured for use in feeds and supplements so it is consistent and affordable. The sulphur that MSM supplies is incorporated into tissues such as collagen and keratin and it is the latter that helps to improve the horse hoof condition.