You can use the small stones to build fences instead of lumber. Your animals won’t be able to get out of inside them and they won’t break like fences made with lumber.
However wild dogs can go right through the rocks and spook your animals so there’s really no point to doing this if you plan to leave your animals outside over night. If you do decide to leave your animals outside which is more trouble than it’s worth in my opinion you have to build wood fences and repair them when they get broken.