This is a Greby's zebra mare and foal.  Notice that the stripes are narrower and closer together than they are on the Burchell's zebra.  The head and ears are proportionally larger also, but that's difficult to detect without seeing the two species side by side.  The Grevy's is more specifically adapted to the dry environment of northern Kenya, and is classified as endangered.  Genetics has a very strong influence on behavior, and there's something about the mental makeup of zebras that makes them unsuitable for domestication.  They are in the same family as the domestic horse, but they are NOT just striped horses.  Speaking of the letter Z, have you ever heard of a zorilla?  It's the African version of the skunk.