The basic motive for Donna J.'s preference for animal sex centered on her resentment towards her social status. She wanted to belong to a wealthy family, and be accepted in more social circles where good looks, expensive clothes and parties were all important. She regarded her own lower middle-class environment with contempt, and saw everything good and, desirable in the social mileau of the wealthier class. This inverted form of snobism led to a dissatisfaction with boys from her own class. Yet, despite her good looks, she wasn't accepted in the moneyed circles.
There were, however, other contributing factors which made the case subject prefer animals to males. She had experimented sexually with a boy from her own class, and one from a wealthier family. Sexually, she found them both incompetent. The physical contact with animals she actually found to be more exciting. Indeed, she discovered the animal… in her case, a dog… was capable of intensifying sexual pleasure. With animals, she discovered at an early age, total sexual stimulation.
In Everything You Always Wanted to Know About Sex by David Reuben M.D., we're told that total sexual stimulation "is a means of intensifying sexual pleasure by utilizing all the available erotic pathways to reinforce and add to the cumulative gratification of the sexual experience. Every available sensory pathway is recruited, first consciously, later almost automatically, to enhance sexual success…"
Donna J. discovered at a very early age that boys, and even many adult men are incapable of giving a girl a total sexual experience. Animals employ all of their senses instinctively and that includes the sense of smell. Without hesitation, the animal either orally or from a coital position entered her anal regions. The rectal odors actually excited the animal. Boys and men, she found were too squeamish for such play.
The case subject's problem with animals was resolved at a later date when she met a man from her own class who filled her with a sense of pride and worthiness and made her realize that material advantages were not everything. When she learned to respect herself and her lover, she found herself capable of finding satisfactory sexual experiences with him. When the need for animal sex was eliminated, her desires for them also vanished.