It is a little weird that he had to shoot the deer to get into its body I mean the deer should still be injured after the shot unless death healed the wound so that the guy would have a body to be in. It is an interesting concept but I wouldn't call it reincarnation because I would think that for that to happen he must be reincarnated within a newborn. Now that I think about it maybe it would have been an interesting idea if he had to kill a soon to be mother doe to speed up the birthing progress and he could reincarnate within the body of a new born deer facing the challenge of running from death still as he would have no protection from a mother.
But enough with my random thoughts. I do like the animation even though that it looks kinda minimal because it works with the concept of death. After all there is barely any energy left to keep on moving or getting usted to a new body. I have to say that you were able to capture the beauty of a deer really well!