I think if one were to come across a dead animal that was a totem of theirs, there would be at least a momentary sadness (until realizing only its shell remained and its spirit was elsewhere). But I don't know that it would necessarily be of lesser or greater import than seeing a live one in happier circumstances. Any noteworthy appearance of an animal leads me to ponder its particular attributes and how it might relate to my present circumstances.

Whenever I come across a dead animal, if at all possible, I'll cover it with earth or leaves or tuck its body under a log. If it was a large animal, like a deer and the kill was fresh, I'd call the police. I know in many rural areas, deer and moose carcasses are taken to local hunters and/or butchers who volunteer to prepare the meat and then deliver it to a local organization to distribute to those in need. Local police would know who to contact.

Please keep in mind that I'm no guru on these matters. I'm just a student of animal nature (including the human animal) who likes to observe and theorize. :)