Ejaculation. Physiology and dysfunction.

The research article is about the physiological process of ejaculation in stallions, the common ejaculation disorders, and potential treatment approaches.

Ejaculation Physiology

• The research explains that key events of ejaculation comprise the emission of sperm and fluids from accessory glands into the urethra, the concurrent closure of the bladder neck, and forceful expulsion of the combined semen through the urethra.
• The emission of sperm and the closure of the bladder neck are mainly mediated by alpha-adrenergically through thoracolumbar sympathetic reflex events. These processes are modulated supraspinally, indicating they are controlled by higher brain centers.
• Ejaculation is described as a sacralspinal reflex, meaning it is controlled at the level of the sacral spinal cord. This process is mediated by the pudendal nerve, which innervates the muscles of the pelvic floor among other areas.

Ejaculation Dysfunction

• In stallions, the most common ejaculation disorders are a failure to emit sperm and a failure to ejaculate. Another issue is the contamination of semen with urine.
• Less frequent disorders include azoospermia, a condition where no sperm cells are present in the semen, and premature ejaculation, where ejaculation occurs before or shortly after sexual penetration.

Causes and Treatments

• The researchers state that, in a large percentage of cases, ejaculation disorders could be a result of musculoskeletal disorders or have psychogenic origins, meaning they are related to psychological or emotional factors rather than being attributable to a specific dysfunction of the ejaculatory process.
• Traditional therapy methods for addressing these deficits can lengthen the breeding life of many affected stallions.
• Pharmacological aids, implying medication or drugs, may also prove useful in managing these ejaculatory issues.