That's actually a really interesting question.. Never given much thought to that.
It may be possible.. humans are animals aswell so when you look at it from a scientific point, it would make sense.. But it would be pretty weird in my eyes!!
Remember that in BD Bella finds out that vampire venom is poisonous to the werewolves and would kill them. I would think that if it's poison for them that maybe it's poison to other animals as well. Then again that's just conjecture and I HAVE NO CLUE. Anything is possible in the mind of Stephenie Meyer...
I don't believe so. I think their venom is poisonous to most other creatures. It's not deadly to humans because vamps were once human. But I think to other species it is mostly poisonous and I don't think it's possible for them to infect cross-species like that.
I do not think it is possible. I think the venom is centralized for the creation of other vampires. All and all if they could change animals they would have creatures of the all kinds watching over their domiciles. I feel that there is a chemical reaction that happens when the venom enters a humans blood. The only other animal I could see being any where close to us would be some specie of monkey.
There is something that makes the venom only work on humans because if it did change animals then from the Cullens feedings we would have a force of undead creatures!! It would cause an epedemic because animals can think like humans but do not act on human abilities. For example, they use primal instincts to feed while we just order a pizza or get something from our home.... There would be utter chaos if animals could be changed.