EMISSION AND EJACULATION
1. Differentiate between emission and ejaculation.
As sexual stimulation increases, a point is reached at which reflex centers in the spinal cord bring about emission and ejaculation.
Emission precedes ejaculation. It results from sympathetic innervation whereby sperm and fluids in the ductus deferens and ampullae are emptied into the urethra along with fluids from the other accessory glands (seminal plasma). The sympathetic innervation provides peristaltic movement for transport to the urethra and constricts the neck of the bladder to minimize reflux (backward flow) of sperm and fluids into the urinary bladder. Once emission has been accomplished, reflex peristalsis of the urethral muscles propels the urethral contents toward the external urethral orifice. The latter phase, peristalsis of the urethra, is assisted by contraction of the bulbospongiosus muscle, which in turn compresses the urethra. The combination of pressure and peristalsis forces the semen (mixture of seminal plasma and sperm and fluid from the epididymides) from the urethra to the exterior, the process of ejaculation. Stimulation for emission and ejaculation is derived from sensory nerves located in the glans penis.Sperm and fluids are ejaculated near the opening of the cervix in cattle and sheep, directly into the uterus in swine, and partially into the uterus in the horse.
■
More on the topic EMISSION AND EJACULATION:
-
Veterinarian -