My donkeys have a large run-in, enclosed completely in winter except for a "door" opening, but they still prefer to go in the barn at night once the weather gets in the low 20's. They do go out during the day, but even then..if its really cold out , they walk up to the door stick there heads out, bray a few times to the horses, turn around and head back to there stalls! They dont get the heavy winter coats our horses have. Corinne