Usually it is a herd and then you run into some real problems. In dealing with WLD, we are beginning to suspect that nutrition plays a big role in keeping WLD in check. A nutrition study really needs to be done on mini donkeys to determine requirements. Donkeys stand around all day stuffing themselves on hay. Hoof growth is provided by protein.
Most protein comes from grain.
We have seen donkeys that are fed hay only that have broken over necks but their hair coats are rough and you can feel their ribs and hipbones. Something is wrong with this picture. This will also make the donkeys get out and move around grazing. Donkeys should not be allowed to get super fat then super thin then fat, etc. You want to keep them fit, just like people are not suppose to have big weight variances.