The baculum (also penis bone, penile bone, or os penis, or os priapi) is a bone found in the penis of many placental mammals. It is absent in the human penis, but present in the penises of other primates, such as the gorilla and chimpanzee. The bone is located above the male urethra, and it aids sexual reproduction by maintaining sufficient stiffness during sexual penetration. The homologue to the baculum in female mammals is known as the baubellum or os clitoridis – a bone in the clitoris.
The penile bone is always present in the male dog, formed by a paired ossification center of the corpora cavernosa at 35 days of age. In large dogs, it is approximately 10 cm long, 1,3 cm wide and 1 cm thick. It is divided into three parts:
Text by Antoine Micheau, MD - Copyright IMAIOS
- The base of the os penis, or caudal part, is truncate and attached to the termination of the corpora cavernosa
- The body of the os penis is straight and long, with athe urethral groove that runs ventrally along the base and the body of the bone
- The apex of the os penis, or cranial part, that tapers gradually and ends in a cartilaginous tip, which is attached by a fibrous strand to the deep surface of the corona of the glans.
This definition incorporates text from the wikipedia website - Wikipedia: The free encyclopedia. (2004, July 22). FL: Wikimedia Foundation, Inc. Retrieved August 10, 2004, from http://www.wikipedia.org
Miller's Anatomy of the Dog, 4th Edition - Evans & de Lahunta- Elsevier