Pizzle sticks are very hard rawhide dog chews made from smoked and dehydrated beef pizzle, or penis tissue. They are also called bully chews. The muscle fibers used in pizzle sticks are twisted together and then cut into chews of between 5 and 7 inches in length.
The word pizzle is used specifically to refer to the penis of an animal. Beef pizzle is almost exclusively eaten by dogs in the form of long-lasting chewing treats, often as an alternative to rawhide chews. Pizzle is a good source of protein, and it acts as a natural plaque remover, cleaning the dog's teeth as he chews.