I never came across a deer that was snake bitten. However as a kid I often saw cows and horse. and even a few dogs bitten by rattlesnakes. None of the animal died of the bite but were pretty sick for a couple weeks. In had a dog that was bitten and he pulled through as well. I took him to the vet but he just gave him an anti-biotic and told me to keep him as quiet as possible for a few days.