Horse colour - Red / Black factor

Red Factor

All horses have a basic coat pigment colour, and can be classified as being Red or Black.

This base coat colour is the foundation of all other Equine colours and the simplest expression of a horses colouring. All other Equine colours are built from the horses base colour (or pigment).

However, there are some horses which genetically are carriers of both the Black and the Red factor, these horses can be considered as being black-based as the black factor is dominant over the red. In other words, a horse which carries both pigment genetics will appear as Black, however it can still pass the recessive red gene to its foals. Horses which are red/chestnut in appearance, carry only the red colour genetics. If the black factor was present, the horse would appear black.

The Animal Genetics Red/Black Factor Test determines your horse's base colour, and presents the results as one of the following:

- A horse that carries only the Black coat colour we abbreviate to 'EE'. This horse is also called 'Homozygous Black' Since Black is dominant, this horse will always produce black-based foals regardless of it's mate.

- A horse that carries only the Red coat colour we abbreviate to 'ee' This horse is also called 'Homozygous Red' This horse will always pass Red to it's foals, however if bred to a Black horse can still produce Black foals as red is recessive.

- A horse that carries BOTH the Red and Black coat colour in its genetics we code as 'Ee' This horse is also called "Heterozygous" A Heterozygous horse can pass either Red or Black pigment to its foals.

Testing is useful to determine if your black-based horse carries the recessive red factor gene, therefore giving you the likelihood and probability of the production of a red foal. This can only occur when the foal inherits the red gene from both parents.

Bay/Brown horses are Black based. Their different appearance is due to the presence of the Agouti Gene (see Agouti testing page)