Prepared from information supplied by the Roan Horse and Pony Society of Australia
Roaning is a term used to describe horse colour, where a horse's body coat consists of white hair intermingled with another base colour. True genetic roans, in addition to having a roaned body coat, have solid coloured heads and legs of the base colour, as the roan gene does not affect these parts of the horse.
Roan colouring is dominantly inherited. In Australia it is most commonly found in Quarter Horses and Welsh ponies and their derivative breeds, including the Australian Stock Horse and Australian pony.
Roan horses can be any colour but the most easily recognisable are chestnut roans, bay roans and black roans. The darker the base colour of the horse the more noticeable the contrast. Roan horses that have lighter colouring, such as palomino or buckskin, can be difficult to detect through visual inspection because of their overall appearance. However, the development of genetic testing has meant that the determination of these lighter roans is now much easier. Grey coloured horses can sometimes be mistaken for roans due to the lightening of their coat, however roan horses are born with their colouring and their head and legs do not lighten over time.
One specific trait of the roan horse is the 'spearing' of the points or the darker colour on the legs. Most horses with darker legs have colouring that terminates in a horizontal line, while Roan horses have darker colouring that tapers off higher up on the leg. Interestingly if a roan horse is branded or their skin is damaged, the hair in those areas will grow back in their solid colouring without white hairs.
The Roan Horse and Pony Society is a non-profit organisation that works to promote and register horses and ponies that are genetic roans. Historically roan colouring in horses in Australia has been seen as undesirable, however this is beginning to change due to the work of the society and roan horse owners and breeders.