The layer of grease in a horse's coat helps to protect the skin from the elements. It seals in moisture and helps repel water, which can help to prevent the skin from drying out and becoming cracked. It also helps to protect the skin from the sun's harmful UV rays.
Prevents tangles
The grease in a horse's coat also helps to prevent tangles. It acts as a natural conditioner that makes the hair smooth and silky. This can make it easier to groom the horse and help to prevent the hair from becoming matted.
Insulates the body
The thick coat and the layer of grease on the hair also acts as an insulator, helping to keep the horse warm in cold weather.
If a horse does not have enough grease in its coat, it may start to look dull and dry. The skin may also become dry and cracked, and the horse may be more susceptible to sunburn and other skin problems.