Hoof Cracking & Capsule Hydration
The ideal hydration level (ie water content) of the various parts of the hoof capsule is as follows –
Hoof wall |
25% to 28% |
Sole |
40% to 45% |
Frog |
65% to 70% |
These are the levels of hoof hydration your horse will maintain given ideal environmental conditions.
The hoof capsule is hydrated internally from within the body of the horse and partially by soaking up water from the environment. There is a nett loss of water to the atmosphere during excessive dry conditions. Too much dry weather and the result is hoof dehydration. (The opposite can occur during excessive wet conditions when the hoof becomes over-hydrated.)
Hoof wall cracks can develop when the hoof is dehydrated or subject to alternating excessive soaking and then drying, for example with rapid weather changes between drought and deluge or when the horse is in basically dry conditions but has the opportunity to spend time standing in a dam.
To check hoof capsule hydration on your horse lift the foot and check the pliability of the sole and frog. The sole should be pliable and you should be able to compress it with your thumbs. The frog should have the consistency of rubber that you can squeeze between thumb and forefinger. The hoof wall should not exhibit cracks or splits.
The hoof capsule needs adequate hydration in order to operate effectively. As the horse moves forward the concussive force is taken up initially by the sole and frog. From there it is transmitted to the digital cushion and dissipated by spreading the heel of the hoof and by pushing against and spreading the lateral cartilage. Thereafter the shock is absorbed by the bone and ligament structure of the leg. This process also aids in the veinal return system, helping to move blood back up the leg to the heart.
Dehydration of sole, frog and hoof wall results in the concussive forces being transmitted directly through the pedal bone and cannon bone. The frog and digital cushion do not operate as intended. This creates a jarring effect that can result in poor gait and lameness.
Long term hoof dehydration can have a number of undesirable effects which reduce the performance of the horse including ringbone, pedal ostitis and general soreness.
Simply allowing or encouraging the horse to stand in water for part of the day does not help – in fact it makes matters worse because it sets up a pattern of rapid hydration, de-hydration and re-hydration which results in more damage to the hoof structure.
