We used to have to fish bones out of the water trough on a regular basis - three times a week or so, was a right pain. Think the foxes used to dunk their kills in the trough or something - can't think how we could so regularly get bones in the trough otherwise??
A very flat dead rat as my mare Sasha stamps on them if they get in her stable,find them now and again on the floor, very squashed.But once she must have picked it up and put it in her water bucket for some weird reason.Gross.