Some horse owners choose to clean their horse’s sheath while some prefer to have their vet do it. Sheath cleaning should not need to be performed more frequently than every 6-12 months. It may not be needed at all for some geldings.
It is normal for horses to accumulate sticky, dark smegma within the sheath, and this normally has a pungent smell. An especially unpleasant smell and increased discharge may signal a problem with a horse’s sheath.
If you do not clean your horse’s sheath yourself, it is good for your vet to do it during a routine exam. You may save money if you suggest they do it along with dentistry.
The most important reason for sheath cleaning is actually the opportunity to examine this area for abnormalities. Tumors of the penis and sheath are relatively common in older horses.
There is great value in having your vet performing the service is the opportunity to examine the penis for abnormalities.
It is usually not necessary to tranquilize your horse if you clean their sheath yourself. Like almost any procedure, with confidence and timing you can teach your horse to accept it.
Keep in mind that the common tranquilizer acepromazine can, in rare cases, cause a horse to have long-term penile paralysis or a state of persistent erection. You should know this before using this drug and use it only under vet guidance.
Wear long plastic gloves, as you will be "up to your elbows" in the sheath. Veterinary obstetric gloves are ideal. Prepare a bucket of warm water with 10-12 paper towels added, beforehand. Have your sheath cleaner of choice ready.
Halter the horse. Either you can hold your horse's lead or an experienced handler can. Stand on the left side of your horse at their flank and facing toward their rear end.
Make contact with the horse and slide your hand down along their belly to their sheath. Place a dollop of your chosen sheath cleaner on your gloved hand. Be very gentle as you initially contact the sheath. if the horse withdraws, keep your hand in place. If they stop moving, remove your hand. This is how you will desensitize them and get them to accept the treatment.
Wet and lather the inner layers of your horse’s sheath. Reach as far up as you can and try to cover all the folds. Allow the secretions to soften for 1-2 minutes before trying to remove smegma from the sheath.
Gently use your hand to explore the area around the sheath, to loosen and remove any debris. Feel the area right around the urethral orifice at the end of the penis for an accumulation of smegma, which often feels like a hard lump of clay, and is known as the "bean.”
Use your finger tips to gently break up and remove this bean. Rinse the whole sheath very well with warm water. Most horses can be taught to accept a lukewarm water hose placed slightly up the sheath. Gather the external sheath around the hose with your hands to block water flow and force water up into the sheath, then release.
Tips for safety & Success
You may want to learn to confidently perform the related skill, Assess Sheath, before you proceed with this skill.
Do not use harsh chemicals or antiseptics to clean your horse's sheath. In our practice, we use very dilute Ivory dish soap. Other vets use various sheath cleaners that may cut through the greasy secretions better. The most common of these is Excalibur, by Farnam.
Leaving soap inside the sheath may cause irritation and swelling so be sure to rinse well.
Acepromazine is a tranquilizer commonly used to cause male horses to drop their penis. It should be used only under veterinary supervision and should not be used in stallions. It may occasionally cause prolonged or irreversible penile drop or erection.