In myths involving bestiality, each animal had special properties. In some cases, the snake characterized purification. For instance, Attia, the mother of Augustus, was "visited" and "purified" by a snake in the temple of Apollo. Besides the bull, the swan, and the snake, we find in the pages of Juvenal, Virgil, and Plutarch, among many other writers, the mention of trained dogs, lions, bears, donkeys, goats, and even crocodiles.
In the Middle Ages, the Church condemned the use of chickens for sexual fulfillment. Maybe it wasn't all just a myth....
