Following on from our previous blog posts No Hoof, No Horse and Hoof Health – make it a priority and reap the benefits, here we explore hoof health still further. Horse care experts Carr & Day & Martin give us some insights into the effects that the environment has on our horse’s hooves.
What makes up our horse’s hooves?
Hoof horn is constructed of two types of keratin molecules – spring-like spiral structures and more rigid zig-zag structures.
Each structure is formed with the assistance of hydrogen bonds within or between the keratin molecules and the two different structures are bound to each other by disulphide links. These spring like structures are able to coil to absorb concussion and shock, whilst the zig-zig structures are rigid and act as dampers similar to the shock absorbers in a car.
Like the rest of the horse’s body, water is an important component and horse’s hooves are at their strongest when they have a stable moisture content of 25%. Hooves in this state do not readily absorb excess water and are in fact strong, durable and able to withstand the stresses of work and shoeing.
What happens if the hoof becomes water-logged?
Water is naturally present and evenly distributed throughout the hoof and is stored in the hoof either free moving or as bound, trapped water. When the hoof is exposed to excessive amounts of water in its environment, moisture molecules flood the hoof structures.
As a result, the hoof swells to accommodate the water which weakens the hydrogen bonds that form the spring like and zig-zag structures. The weakened hydrogen bonds cause the shock absorbing springs to become stretched, elongated and unable to re-coil.
The hoof structure is therefore changed and ceases to act as a shock absorber. Hooves in this state may look surprisingly healthy, as any minor cracks tend to disappear due to horn expansion. However, the horn is weakened and prone to being soft and crumbly. It is not surprising therefore that shoes are easily lost, especially in heavy-going.
How does the hoof become dry and damaged?
On a hot day, if a water-logged hoof dries out too quickly, irreversible damage can occur to the molecular structure. Rapid removal of moisture from the hoof does not give the spiral and zig-zag structures enough time to re-align. Hydrogen bonds stretch, break and are unable to reattach and realign, so the structure collapses.
This damage can cause the horn to become dry, brittle and often exhibit cracking. Always remember, it is this rapid removal of moisture that causes the damage, so be careful to ensure that your horse’s hooves do not dry out too quickly when wet.
The optimum 25% moisture content is extremely difficult to maintain, especially in wet and changeable climates. More important than achieving a reasonably dry hoof is regulating and stabilising the moisture at a constant level. Maintaining a consistent moisture level allows the molecular structures of the hoof to adjust gradually to change, so damage does not occur.
The key to managing the moisture content of the hoof is understanding the environmental conditions that affect it.
The hoof structure is damaged by rapid fluctuations in the moisture content. Saturation of the hoof in wet winter conditions, and rapid drying during the summer months causes huge moisture imbalances. The rapid drying of a saturated, weakened hoof causes molecular disruption, resulting in visible cracks and splits.
Once weakened by saturation, the hoof becomes more porous, easily absorbing water from summer showers and morning dews. Excess water causes hooves to become waterlogged and weakened in a similar way that our nails become weak and pliable if we spend too long in the bath. However, on a warm day this excess moisture can dissipate quickly, exacerbating existing damage.
There are a wide range of products available from your local tack shop to help keep your horse’s hooves in tip top shape. The sensitive nature of the hoof is well recognised, but there is no simple, single solution to remedy all hoof problems, so management is essential. Carr & Day & Martin’s traditional and essential products have been tried and trusted for everyday care to maintain, improve or protect hoof quality.