I know the colder it is outside, the more hungry I get. I think it’s the same with the sheep and donkeys. When it’s cold out they have little patience for anything more than carrots and hay.
The pasture is covered in a thin layer of snow, that they can easily graze though. So they keep busy during the day, but the winter grass has no nutrition in it.
Feeding the animals twice a day is just one of the many pleasures of having them.