I know there's a lot of places to keep a horse, however - would it be ok to keep a horse in a pasture, with grass, and some form of shelter? Don't horses have to meet up with certain humane living conditions? I would think a horse does not HAVE to be kept in a stable all the time, correct? Also if a pasture would do, what would you do in the winter, if you don't have a barn? Can anyone help me?