These are features that, while they may be associated with one breed, may occur among other breeds of horses.
Feathering refers to growth of hair above the hoof. An extreme example of this are the feathers on the feet of a Clydesdale team. Heavy feathering is common in the draft breeds. For many light breeds the feathering, if present, is clipped for horse shows, and in general just because it gets dirty. Photo from Wikimedia.
Dorsal Stripes are lines down the horses back, on a bay horse, like the one in the photo the stripe is often black. This is often associated with dun colored horses but is also apparent on other colors. Donkeys often have this feature too. Photo from Wikimedia.
Striped hooves are often seen on horses in combination with ermine spots, this being where they have white hairs on the lower leg and darker spots of color. However that is not the case here, as it is associated with the color silver dapple. A striped hoof is said to be stronger than a solid colored hoof. The photo is from Wikimedia.
Dappling and the Silver Dapple
This horse is of a rare coloration called the “silver dapple”. This particular color only exists in some breeds. As unlikely as it may seem this gene is in combination with the gene for a horse being black. They are really more of a chocolate brown and often are darker in the summer than in the winter. Any breed of horse may be dappled, the “dapple” is the spotted effect of a lighter color against a darker one. Regular grooming enhances this effect. Photo from Wikimedia
A horse who is has gone grey and her foal. Believe it or not she was born a solid color (like her foal) and over time she turned grey. If her foal has the grey gene, it will turn grey too. Some horses turn grey faster than others. In this horse you can also see what is known as “flea bite” pattern, which is flecks of darker hair, and not due to fleas at all. Many grey horses also exhibit dapples as they fade to grey. You can tell this horse is grey, rather than white, because it has dark skin on her face, and some of her hock (part of the hind leg) is still dark. White horses are very rare. Photo from Wikimedia.
In contrast to grey, a roan horse, is born roan, and will not change colors. They have white hairs mixed throughout their coat evenly, with the exception of head and limbs, which remain darker. This horse is a referred to as a Red Roan because his base color is chestnut. If bred to a solid color horse, he has a 50/50 chance of producing solid colored foals or roans. Two roans should never be bred together because 1 in 4 combinations will result in a foal born dead or aborted. This is called a lethal gene. Photo is mine from Picable.
There are several spotted patterns in horses. Often people make the assumption that all spotted horses are either “Paints” or “Appaloosas”, but these are breed names and not color types, there are many breeds who can have either of these color types so correctly if you do not know the breed you should call them Pintos, for horses with large splotches, or by what ever pattern the horse has, there are many spotted patterns. To get into more detail would require a whole other link. The horse on the left of this photo is a pinto, the horse on the right is a leopard pattern Appaloosa. Picture by Jean-Pol Grandmont, from Wikimedia.
Horses eyes are normally brown. Blue eyes are common in horses where white extends near, or around the eye socket. As such it is common in Pinto horses, like we just talked about above. This is often called “wall-eyed” or “glass-eyed”. Blue eyes do not effect a horses vision. This photo is mine from Picable.