A thought...
I am on the second season, and here we see a few zombie animals as well - fair enough, why wouldn't they turn? Anyway, if animals turn into zombies... fish, game, birds, insects, etc., there is no way to survive a zombie apocalypse. Think about it, in a world where animals eat animals, and when an animal dies - by any cause - it turns, etc. Earth will exponentially be gone zombie within a few weeks. Animals of all kinds and sizes will hunt any human survivor... you name it.
My point is: the dream we all have (to various degrees) of roaming the earth in a post-zombie apocalypse world must be without animals turning. It has to be humans exclusively.