Its hard to know when your dog is trashing on a deer. We can usually tell if its a deer when the dogs cover a mile at record speed and then come back because they got left in the dust. Our dogs figured out that they cant catch a deer or get one to bay up. They usually leave them alone now.
My trashy dogs only run a deer for a few hundred yards then come back pretty quick. We know their on a hog if they get out there and stay hooked for awhile.