I don't know if its a felony in the UK, but I'm sure its illegal.
In most of the states in the US its certainly illegal, but not all. Some states have removed any criminal penalty for sexual conduct with an animal, undoubtedly figuring that a jail is not the appropriate place to put someone that sick.
Can we defeat the terrorists with "Blow up" sheep? Drop hundrends of thousands of "blow up" sheep in terrorrist areas? C4 equipped?