Jeske Noordergraaf, VMD

 Male horses need their sheath cleaned on a regular basis.  Or, as some people say, they need to be "beaned".  Sheath cleaning is often done as part of the spring "tune-up".  We are frequently asked how male horses survive in the wild without having this done.  There are only stallions in the wild, no geldings.  These stallions are busy breeding mares which keeps their penis clean.  

Horses are able to telescope their penis and keep it retracted into their prepuce. The penis  is composed of erectile tissue and includes the extrapelvic part of the urethra.  The prescrotal portion is situated in a cutaneous pouch, the prepuce or sheath.  It is cylindrical in form but much compressed laterally in the greater part of its extent.  The urethra protrudes from the end of the penis as a free tube and is named the urethral process.  There it is surrounded by a circular fossa which opens dorsally into the urethral sinus, a bilocular diverticulum, or pocket,  lined by thin skin.  This diverticulum is filled sometimes with a thick, caseous mass of sebaceous matter and epithelial debris, otherwise known as smegma beans. 

Geldings retract their penis and may only drop it when they are urinating or very relaxed.   Male foals (colts) may not drop for weeks after they are born and then they may hang it down all the time.  As problems can develop on this part of the body, the penis needs to be examined at least once a year.  Tumors can develop,  smega beans grow and I have even seen maggots in the diverticulum.  All of these are problems that need to be addressed to prevent more serious issues. 

The signs that a horse exhibits when the sheath is dirty includes black tarry dirt on the inside of the back legs, a swollen prepuce, old scaly skin on the penis and an itchy tail.  If the bean is very large, the horse may have trouble urinating also.   

Smegma beans are so named because they resemble beans in shape and size.  They are produced by the glands in the skin at the tip of the penis in the urethral diverticulum or pocket and put pressure on the urethra.   They can be removed with gentle pressure.  The ones that are very large may need to be broken in half to pass out the opening.   

So, can you clean this yourself as a horse owner?  Yes you can but not all horses are appreciative of having this done.  Also, it is much easier both to do and to be more thorough if the horse is relaxed and the penis is hanging down.  Tranquilizers are very helpful in performing this service as it is hard to stand completely out of reach of the hind legs.  Take good care of your geldings and keep them bean free.