One of the most attractive attributes to a horse is their long wild flowing manes and tail. Each animal has unique hair, yet all as beautiful as one another. However hair on the upper lip in the shape of a mustache is a less commonly known place for horses to flourish hair growth.
Mustaches are common with breeds such as the Gypsy Vanner horse breed, who are known for their gorgeous flaxen coats, flowing hoof feathering and full luxurious manes and tails. The facial hair that this breed sports is linked to the gene which produces heavy growth of hair in other places on the horse’s body.
The Gypsy’s are not the only horses to grow mustaches however, as the gene of hair in horses is cumulative. This means that the more copies of the gene in the animal will produce more hair. Therefore certain horses will have more copies and as a result, more hair. This is a valid reason for why not all horses grow mustaches whilst others do.
The Shire breed is another horse that mustaches are common with. Mustangs and Quarter Horses also grow mustaches to protect them from the cold. Some horses will grow them in winter and shed them in summer as a kind of upper lip winter coat.