It’s easy to forget just how amazing an organ the skin is. It envelopes us and our horses, protecting our internal organs from our environment, helping us maintain a constant temperature, produces vitamin D in sunlight, and acts as a sensory apparatus.
The skin consists of two main layers, the outside of which called the epidermis, and is composed of specialised cells called keratinocytes. These cells consist of a tough protein, and by the time they are pushed to the surface, they are dead and flattened, giving a resilient, waterproof outer layer to the skin. Millions of these cells are worn off daily, but replacements continue to migrate up, a process that gives skin its remarkable healing power. Underneath lies the dermis, the layer that supports and nourishes the epidermis, which is well furnished with blood vessels. The dermis is rich in elastic fibres and connecting, non-elastic collagen, both of which allow the skin to move and flex with the body.
Overlying the horse’s skin is a coat of hair, which gives them thermoregulatory powers to enable them to survive comfortably in a wide range of environmental temperatures, is involved in sensory perception and acts as a barrier to protect the skin. Every single hair follicle has a small muscle attached to it, which can make that strand of hair stand up to help trap air, keeping the horse warm. Horses grow a thickened winter coat in response to shorter day-length and a drop in temperature, which they shed in the spring.
The horse’s skin is prone to a variety of problems, from tumours to allergies to infections. The horse can be affected by warts, sarcoids, melanomas, bacterial and/or fungal infection causing mud fever and other types of dermatitis, allergic reactions (which may cause hives) from a variety of sources including insects, external allergens or feed components, ringworm, lice and mites. The skin can also be affected by wounds, which compromise its defence system. However, the skin has remarkable healing powers and, providing infection is controlled, even the most horrific-looking wounds often heal without complication. Wounds on the legs where the skin moves tend to heal less efficiently than those on the body.
Keeping our horses’ skin healthy relies on – you guessed it – a balanced diet, but you can add other nutrients on top of a balanced diet for extra benefits. Balancing a forage diet correctly is key for healthy skin because some of the minerals that are short in all UK grass are essential for healthy, resilient skin and hair. Always feed a multi-vitamin and mineral supplement or balancer to horses fed less than the full recommended amount of a fortified compound feed. Nutrients that may help challenged skin, on top of a balanced diet, are the omega-3 fatty acids, zinc, MSM, vitamins A, C and E, and amino acids glutamine and arginine.