The clinical signs of urethral defects are limited to hematuria at the end of urination, associated with contractions of the bulbourethral muscle in geldings or with hemospermia and decreased fertility in stallions. All breeds may be affected, although the disorder seems more common in Quarter horses.
Diagnosis of a urethral defect is based on clinical signs and urethral endoscopic findings. The urethral defect is seen in most cases on the dorsal convex surface of the urethra at the level of the ischial arch.
Some cases of urethral defect may heal spontaneously, but most continue with intermittent hemorrhage, although anemia is very rare. Breeding rest is recommended for stallions. Subischial perineal urethrotomy or corpus spongiotomy reduces vascular pressure in the corpus spongiosum during urination and ejaculation, allowing the defect to heal. A buccal mucosal graft and topical cautery have also been used to repair the defect.
Glass KG, Arnold CE, Varner DD, Chaffin MK, Schumacher J. Signalment, clinical features, and outcome for male horses with urethral rents following perineal urethrotomy or corpus spongiotomy: 33 cases (1989-2013). J Am Vet Med Assoc, 2016, 249(12):1421–1427.
Also see pet health content regarding noninfectious diseases of the urinary system in horses.