The Horse’s Foot
By Linda Kennard, NAF
The horse's hoof has developed over millions of years, approximately 50 million, giving the horse a selective advantage in the environment in which they live.
We have all heard the expression “no foot, no horse” but how much thought is given to this, and, is the hoof taken for granted?
It will take anywhere from 9 months to 18 months for the hoof to grow down from the coronary band to the ground. This means that anything happening to the horse, either a specific trauma to the hoof or a systemic problem, can affect the hoof for a long time.
STRUCTURE
The outside of the hoof is like a modified fingernail and consists of tubules that grow down from the coronary band from the sensitive papillae along with flattened cells. In between these structures is a protein called keratin.
There are three basic layers of the hoof wall from the inside to the outside. The stratum externum, the stratum medium and the stratum internum.
The stratum externum is only a few millimetres thick and due to its rubbery nature gives the hoof a “waxy” look. The purpose of this wax-like coating is to prevent dehydration of the hoof structure.
The stratum medium makes up the bulk of the hoof wall with the pigmented horn tubules.
The stratum internum is non pigmented and consists of approximately 600 laminae that interlock with the sensitive laminae of the laminar dermis.
The sole and the frog are formed separately by a layer of young cells which form a sheet across the sole of the foot. The dermis of the sole is firmly attached to the undersurface of the coffin bone.
The area where the sole and the wall meet is know as the “white line” (zona alba).
FUNCTION
The main function of the foot is to protect the inner soft tissue as well as helping to absorb concussion when the hoof strikes the ground. The bulk of the horses weight is carried by the hoof wall, with some weight taken by the frog.
In a normal foot the sole is not a prime weight bearing surface and only comes into contact with the ground on soft surfaces.
It is therefore essential that the horn is of a good quality to fulfil these functions.
If the horn is too soft it will not be able to protect the inner structures from bruising and if it is too brittle it will crack and split. Resulting in the horn being unable to absorb the shock on contact with the ground. However, the hoof wall is not rigid and will distort as it takes weight. At the same time, in a normal foot, the heels will expand during weight bearing.
The physical movement that the hoof experiences during weight bearing is one of the major ways that blood is pumped through the structure of the foot and is also responsible for pumping blood from the foot back towards the heart.
HOOF CARE
The overwhelming factors that contribute or detract from a healthy foot are nutrition and management. A bad diet and poor management can ruin even the best foot.
There are several nutritional factors that are important to normal hoof growth. It is essential that there are adequate protein and trace minerals to build a healthy foot.
The protein structure of the hoof is loaded with sulphur containing amino acids, therefore bio-available sulphur is important to normal hoof growth. The sulphur containing amino acids methionine and cystine are two of the more essential ones. Low sulphur will decrease keratin synthesis which is important to the stratum internum and the laminae bridges that interlock with the sensitive laminae of the laminar dermis. The sulphur protein calcium and the vitamin biotin are also essential for normal hoof growth.
The beneficial bacteria in the horses large intestine produce the vitamin biotin for the horse to use. However, if the horse is stressed or has an imbalance of good bacteria there will result in a biotin deficiency.
Essential fatty acids should also be made available. These are important for skin health and contribute to coat condition as well as moisture content and pliability of the hoof structure.
The last area not to be ignored is the liver. The liver is of great importance to the horse because of the complex part it plays in the horse's body and in particular the part it has in digestion. It is the largest gland in the body. Therefore liver function is reflected in the horses total system. Diseases involving the liver produce symptoms involving a wide range of systems within the horse, including the health and quality of horn growth, this reflects the importance of this organ.
If the composition of the hoof wall is abnormal, from nutritional deficiencies, it will be unable to withstand the forces that the normal hoof is designed to withstand.
RECOMMENDED NAF PRODUCTS:
PRO FEET; Biotin; Hoof and Hide, Hoof Moist and Hoof & Sole.
For details of your local stockist please call the Freephone Advice Line: 0800 373 106 or
email info@naf-uk.com
