zoophilia, n.
A paraphilia, defined as an affinity or sexual attraction by a human to animals.
Such individuals are called zoophiles. The more recent terms zoosexual and zoosexuality also describe the full spectrum of human/animal attraction. A separate term, bestiality (more common in mainstream usage), refers to human/animal sexual activity. The two terms are independent: not all sexual acts with animals are performed by zoophiles, not all zoophiles are interested in being sexual with animals.
From Wikipedia