We do not speak of the horse's fur, but of the horse's coat. The manes, skin and eyes are also part of the coat. And the coat can be of different colours with different shades. However, the barnacles, the head and the ears are not part of the coat. Finally, the term "coat" is often related to the term "breed".
Horse coats and genetics
Coats and genes
Coats are part of a classification established by the National Studs in order to be as close as possible to their genetic reality. They are therefore classified by family such as bay, chestnut and black. In order to obtain very particular coats, breeders must have some genetic knowledge, i.e. know the specific genes involved and how they are expressed. However, genetics can cause more or less pleasant surprises, such as diseases caused by a specific gene.
Coat specificities and diseases
In some breeds of horses, there are specificities linked to genetics. In the case of the piebald horse, for example, this is the Overo Lethal Foal Syndrome (OLFS).
This syndrome involves the following situations :
- If the overo allele is present in a single copy, it results in an overo coat (white spots on the head and belly).
- If two copies are present, the foal is white and dies several days after birth.
- Furthermore, if a breeder wishes to cross 2 overos, there is a very high probability of having an overo foal and a 25% risk of having a sick foal.
- The ideal is therefore to make a cross with an overo and a plain mare. In this case, the risk of mortality or disease is almost nil because the foal has a 50% chance of being overo.
2 families of horse dresses
We distinguish 12 coats classified in 2 families (simple and compound coats). In each category, one can find shades such as brown bay or solid black.
Simple horse coats
There are 4 simple or basic coats which correspond to a single colour of hair on the body, manes and legs :
- White : this is actually a pink depigmented skin. True white is very rare as a very light grey horse can be called white by novices.
- Black : as with the white horse, it is exceptional to see a true black horse, as it is often confused with the dark brown bay coat. The black coated horse also has black skin covered with black hair.
- Chestnut : This corresponds to a coat with fawn hair and mane (sometimes with some shades of fawn). The skin is black. There are golden chestnut, copper chestnut and burnt chestnut.
- Coffee : The horse has a nice golden colour with washed manes which must not, under any circumstances, be black. Officially, this coat is only permitted for imported ponies and horses.
Compound horse coats
There are 8 compound dresses. However, they can be composed of 2 or 3 colours more or less separated or mixed :
- Bai : there are several types. It is composed of identical red hairs all over the body with black manes and extremities of the limbs.
- Isabelle : the body is of uniform colour while the manes and extremities are black. The hair may be light, ordinary or dark yellow. This colour is not present in all breeds.
- Mouse : The body is also of a uniform ash-grey colour, more or less dark, with black manes and extremities. Other coats such as grey, aubert and louvet have mixed hair colours identified all over the body, manes and legs.
- Grey : black and white hair mixed on black skin. The grey can be dapple, slate or iron. The horse tends to become much lighter as it ages.
- Aubert : white and red or yellow hair mixed together. As with the isabelle coat, it can be light, ordinary or dark. The presence of multiple patches of red and white hairs is called the yarrow or peach blossom coat. On the other hand, the coat is peachy if the colour is similar to that of the peach blossom.
- Louvet : red or yellow hairs mixed with black hairs which seem to lighten from the tip of the hairs to the base.
- Rouan : 3 colours of hair evenly mixed over the whole body, the mane and the limbs. Composed of red, black and white hairs, the roan coat can be light, dark or vinous.
- Piebald : This coat is composed of the white coat associated with the bay coat, the alzan coat or the black coat. We can even find aubert, roan or café au lait. It is presented in patches. For example, with a predominance of white, one would say piebald chestnut.