Q: Is it true a cat’s penis is barbed?

Answer: The penis of the cat is unusual in being covered in about 120 barbed spines, or papillae, pointing towards the base of the penis. They disappear two to four months after castration. Deflection of these papillae during mating produces sensation which probably stimulate the discharge of the semen. With repeated mating the papillae may pick up hair from the hind quarters of the female. This can accumulate as a ring of hair around the base of the penis which has to be removed before further successful mating is possible. It is also thought that the sensation produce by the barbs as the penis is withdrawn stimulates the vagina of the female and induce ovulation.