Functional, developmental and clinical anatomy of the bovine penis and prepuce.

Abstract

Several changes in nomenclature from that of the Nomina Anatomica Veterinaria (4th edition) are suggested. The neuromuscular mechanisms of erection and ejaculation involve activity of both smooth and striated penile muscles. Functional and clinical anatomy of the penis and prepuce are considered for these five main stages of service performance: sexual arousal (which prepares for erection and ejaculation); penile erection and also its failure (impotence); intromission and its failure; ejaculation and associated clinical problems; detumescence and repositioning of the penis after service. Preputial mobility and injuries are also discussed. Anatomical changes of the corpus cavernosum penis during erection are described and related clinical problems are discussed, under three headings: Penile elongation and distension; Straightening of the sigmoid flexure; and Spiraldeviation of the penis. Prenatal development of penis and prepuce is described. Postnatal development is then considered with special emphasis on clinical problems in the young bull.