The cells of the hooves are among the most metabolically active in the body because they are constantly being worn away and need to replace themselves. Because of this, any gaps in their nutrition shows up as slow growth or poor hoof quality – or both!
The major structural protein in hooves is keratin. Keratin, like all proteins, is a strand of amino acid units. Alanine, glycine and the sulfur containing amino acid cysteine (produced from methionine) are the primary amino acids in keratin.
Alpha-keratin is the predominant keratin found in mammalian tissue, from hair to hoof horn. Beta-keratin is tougher keratin found in the outer skeletons of insects but may also occur to some extent in mammalian tissue, like human fingernails. The tubular/helix structure of alpha keratin is carried over into the larger structural unit of horn tubules in the hoof wall.
Since the hoof wall is well over 90% protein on a dry matter basis, it’s worthwhile talking about the keratin a little bit more. Alanine and glycine are in abundance. These are nonessential amino acids easily generated from pyruvate and a methyl group from one of the branched chain amino acids or by removal of one carbon from the amino acid serine by tetrahydrofolate to form glycine. This reaction requires pyridoxine (B6). We can now identify several dietary factors that may limit hoof quality on the protein end of things:
- Branched chain amino acid deficiency (unlikely except with heavy work).
- Protein deficiency in general
- Methionine deficiency
- Inadequate vitamin B6
Another very important B vitamin which may be deficient is biotin. Biotin plays an essential role in both the growth rate and integrity of the hoof wall.
The outermost layer of the hoof wall (stratum externum) also contains a variety of fats and waxes, as does the “hard”/dead portion of the hoof wall in general. The stratum externum grows down from the epithelial cells of the periople, located below the coronary band. When present in correct amounts in an unbroken layer, these seal the internal moisture into the deeper hoof structures and seal water out. https://www.jlr.org/content/25/12/1320.full.pdf+html?sid=63bf0c47-2189-4028-9271-39cbd8aeeba5 .
On the mineral end, a balanced diet with adequate levels of especially calcium, zinc, copper and selenium is important to support hoof health and growth. High dietary and/or water levels of iron, manganese or sulfate can interfere with copper and zinc absorption. Zinc is especially important for both growth and strength of walls and connections. Both zinc and copper are critical to strong immune defenses in the softer tissues of the hoof as well as enzymes which provide antioxidant protection for the hoof.
The hoof wall grows down from the coronary band at the top of the hoof. This is a highly vascular tissue which depends on its blood supply for constant delivery of nutrients. The herb Gynostemma pentaphyllum [Jiaogulan] helps maintain good blood delivery to the foot via production of nitric oxide which dilates the blood vessels. Gynostemma also supports the release of growth factors which encourage development of a strong network of capillaries and the production of new tissue.
Robust hoof growth is a combination of attention to diet to provide all the needed nutrients and support of blood flow to the hoof.
Eleanor Kellon, VMD