To clarify the scene of the foal's birth in this movie -- it was a DISNEY movie! Thus, the birth was not actually shown! They showed the mare laying down and some sound effects of grunting, then showed a long legged young black foal -- definitely NOT a newborn -- standing there.
One other thing that I found fascinating in this movie --- in the desert race scene, the villian's chestnut stallion was running at a full out gallop right alongside another stallion. The chestnut had his ears pinned flat back and was literally snatching and biting at the other stallion's neck! I guess it might have been computer generated, but if so, it was incredible to watch....