Conditions or ailments that are the cause of a problem that you see - your observation.

Your vet may diagnose

Sheath Smegma Accumulation

Synonyms: Bean of Significant Size Present


Normal male horses produce a fatty secretion from the sheath surface known as smegma. Each horse is an individual and produces different amounts, types and odors. Management, stabling, exercise and a variety of factors also contribute to how "dirty" a horse's sheath becomes.

The development of large masses of smegma (beans) in the urethral fossa at the tip of the penis is common in geldings, especially those that are kept in stalls. In most cases, beans do not cause any obvious problems and are noticed when someone palpates the area or cleans the sheath.

However, beans may cause urine spattering and sheath swelling as they get larger. In rare cases, they cause painful or difficult urination. An extremely large bean can actually cause signs of colic.

my vet's role



my role


I might observe

You might make these observations when a horse has this condition.

Very Common
Less Common
more observations

Questions To Ask Your Vet:
  • How frequently should my horse's sheath be cleaned?
  • Can my horse's management and bedding be changed to lessen this problem?

Periodically assess this area. Remove beans before they grow large.

Author: Doug Thal DVM Dipl. ABVP