"'Do not have sexual relations with an animal and defile yourself with it. A woman must not present herself to an animal to have sexual relations with it; that is a perversion.
Quote straight from the new international bible.
Perversion - a perverted form; especially : an aberrant sexual practice or interest especially when habitual.
According to Webster...
For those that say that animals cannot give consent, I would like to say that animal breeders already violate the animals with other animals. If they can do this, why can't they be a little more direct (sorry, trying not to be too descriptive). Not everyone is a Christian. What if someone's religion said they had to be an animal lover (again not too descriptive)? I take a real libertarian view on this. If we are going to prevent bestiality on the account of the animals, then we need to protect the animals from murder for food as well (except chicken, sorry).