What role does sulphur play in your horse’s hoof health?
‘No foot, no horse’ is a well-known saying in the equine world, and nutrition is a key part of maintaining optimum hoof health. When considering hoof nutrition, the emphasis tends to be on biotin, methionine and zinc, and all of these have their roles to play within the complex hoof, but have we overlooked one of the main players? What role does sulphur play in your horse’s hoof health?
A common element, sulphur is the fifth most abundant element by mass on Earth, and is an integral part of all plant and animal systems. Many sulphur compounds are strongly aromatic, such as garlic and natural gas. For horse owners, the distinctive aroma of hot shoeing is due to burning sulphur, and that sign alone tells us that sulphur-containing compounds are key constituents of hoof horn.
Sulphur in the Body
Within the body sulphur is most closely associated with the amino acids methionine and cysteine, though it is also found in B vitamins, such as biotin. Therefore, we start to see that many of the nutrients we associate with hoof health are, themselves, sulphur containing. Due to it’s role in amino acids and protein, most of the body’s total body sulphur is in the muscles; however, the highest concentration is certainly within the hoof wall.
Sulphur and Keratin
The concentration of sulphur in hoof is due it’s integral role in ‘keratin’ – that tough, fibrous structure that gives hoof horn it’s strong, but flexible, properties. For keratin production, the sulphur-providing compound, methionine, is essential. In fact, methionine is classed as an ‘essential amino acid’, meaning it must be provided in the diet, as horses cannot produce methionine itself. Once ingested one of methionine’s roles is in the production of the cysteine and on to cystine, the principle building block of keratin.
Dietary Sources of Sulphur
The main source of dietary methionine and sulphur for horses is through botanical proteins, usually well provided by fresh grazing. However, as we move into autumn, levels in preserved forage are lower, meaning protein and sulphur deficiencies are more likely when horses’ diets rely on hay and haylage.
When natural sulphur is low it’s often biotin that we go to first. However, as biotin can be naturally produced by the microbiota of the hindgut, why do we also need to supplement it? In fact, the dietary route for biotin is often considered preferable to the natural production, as microbial synthesis takes place past the point of optimum absorption for vitamin like substances, i.e. the small intestine. Research in horses has found improvements in hoof quality with supplementary biotin, with some trials also showing improvement in hoof growth rate. The research shows that when supplementing with biotin patiences is required as an improvement takes many months, reflecting the length of time required for hoof growth. Once established on a daily biotin supplement it is advised that the horse stays on it for long term maintenance, as research shows when that is stopped the hooves return to pre-supplement condition.
What does MSM stand for and why is it important?
However useful and important the plant based amino acids and dietary biotin can be, if we consider these to be our only sulphur sources we are missing a very significant source. Methyl sulphonyl methane, goes under a number of different names, but we usually know it best simply as MSM.
MSM is an organosulphur compound, and is highly sulphur rich, being 34% sulphur, compared to, for example, methionine at 21.5% or biotin at 13.1% sulphur. Trials in mammals show MSM to be rapidly assimilated, and evenly distributed through the system. MSM not only has the ability to directly donate sulphur to the system, but has also been shown to be a source of sulphur for both the methionine and cysteine, particularly for the essential amino acid, methionine, which then feeds keratin through the cystine production discussed above.
As with the plant based sulphur amino acids, the level of MSM drops markedly once fresh forage is preserved, either through drying to hay or ensiling to haylage. Therefore horses regularly stabled, or travelling regularly, with a greater reliance on preserved forage, may be sulphur deficient, both through lower levels of methionine and cysteine, and lower levels of MSM.
Since first introducing MSM to the UK market back in the 1990s, the Vets and Nutritionists at NAF have recognised the role of MSM as central to hoof health. Working in synergy with methionine, biotin and zinc, MSM plays a crucial role in the results seen with ProFeet.
“I can safely say since recommending PROFEET to my customers not only have we witnessed good hoof growth, but the quality of horn has appeared to be stronger and more resilient. Giving me more hoof to work with from visit to visit and the horse a great hoof to perform on.”