Male accessory gland

The accessory glands of male mammals secrete fluid for nourishment of sperm and sexual attraction.

Accessory glands

The male accessory glands are the ampullary gland, seminal vesicle, prostate, bulbourethral gland, and urethral gland.

The products of these glands serve to nourish and activate the spermatozoa, to clear the urethral tract prior to ejaculation, serve as the vehicle of transport of the spermatozoa in the female tract, and to plug the female tract after placement of spermatozoa to help ensure fertilization. Although the glands are usually described as being branched tubular or branched tubuloalveolar, they vary in their organization and in their distribution in different species.

Ampullary glands

Each of these branched tubular glands lined by simple columnar epithelium is an enlargement of the vas deferens in its terminal portion. These are typical tubular glands in ruminants, horses and dogs; absent in the cat and poorly developed in boars. The function of the white serous secretion is not known.

Seminal vesicles

The secretory endpieces of these glands are lined with simple columnar epithelium; the main ducts are lined with stratified columnar epithelium. These glands do not occur in carnivores, but are present in some form in horses, ruminants and swine. Seminal fluid, the product of this gland, serves as a vehicle for the transport of spermatozoa.

Prostate gland

Grossly the prostate gland can be divided into two parts: the body and the disseminate part. Low cuboidal to low columnar epithelium provides the lining for this compound, tubuloalveolar gland which consists primarily of serous secretory end pieces. The secretion of this gland is more serous in dogs and more mucous in bulls. It serves to promote the movement of spermatozoa and to form a vaginal plug. Additionally, in bulls, the secretion contains high amounts of fructose and citric acid. Concretions may be present in the secretory end pieces as well as parts of the duct system. The prostate and Cowper's glands are the only male accessory glands in marsupials.

Bulbourethral glands

The lining of these paired, compound, tubuloalveloar glands is simple columnar epithelium. A capsule of dense connective tissue contains some smooth muscle as well as skeletal muscle of the bulbospongiosus and urethral muscles. All domestic species have these glands except the dog, and their mucus secretion serves to clear the urethra of urine and to lubricate it and the vagina. The product may also serve as an energy source for the spermatozoa.

Urethral glands

In some species, branched tubular mucous glands are found along the length of the urethra, especially dorsal to the lumen of the urethra. The exact function of their product is not clear.