I just spent several hours taming a wolf and put it on follow. It followed me near a swamp area and proceeded to attack a Draugr. The Draugr killed it and I was pretty upset. I spent hours taming the wolf only to have it die within 30 minutes.
There should be a way to resurrect your pet or at least let it self heal. I cannot tell you how disappointed I was that all my planning and work (taming the wolf) went up in smoke within minutes.