Last Updated on March 18, 2022 by Allison Price
Smegma. This is a very strange word. It’s a new year, and it’s always a good idea to learn something!
Definition of Smegma
Wikipedia says Smegma is a mixture of skin cells that have been shed, skin oils, and moisture. It can be found in both male and female mammalian reproductive genitalia.

Although it sounds disgusting, this happens in both male and female mammals as well as horses and humans. You may also have smegma. We are referring to the sometimes nasty, flaky stuff that you find on your horse and sometimes your mare.
Where can I find Smegma?
Penis drops from sheath
A sheath is a double-folded skin covering the penis of a male horse. The sheath can get dirty and sometimes smelly. Sebum is secreted by the sheath’s sebaceous glands. Sebum can mix with dirt or sloughing skin cells to make smegma. It can be gray, tan or black and turns into a soft, waxy substance. You may find flakes of hardened smegma on the penis.
Flakes of the smegma
The smegma can cause irritation to the sheath or penis if it is allowed to build up. However, the smegma should be more of a penis protector and lubricant than a lubricant. A large sheath swelling on a horse is an indication that there is something wrong.
Beans
If the horse’s sheath has become extremely dirty, the smegma may mix with dirt, sweat, and mineral salts from his urine to form “beans”. Beans feel and look like hard gray bubble gum. The urethral fossa is where beans accumulate. This is the area at the penis’ free end.
It can cause irritation and even infection if the bean grows too large. A firm mass near the penis is a sign that the bean has been removed manually. You should get rid of it as soon as possible.
Multiple beans taken from 1 horse
Sometimes, you may notice that the stream of urine they are urinating is not straight or even dribbles. Another sign that a bean might be present is the dribbling stream. Sometimes the force of urine will pull the bean out, but other times it won’t.
What can I do about the Smegma
There are two options for dealing with smegma. You can call your veterinarian to clean your sheath. Or, you can roll up your sleeves and use some gentle soap and water to clean your hands. You should remember that if your horse has a bean, it might be painful and may need to be sedated. This is when you should call your veterinarian. There is another option: do nothing. Most horses will be fine with their sheaths not being cleaned, but it is important to monitor the horse’s behavior and be aware when they may need help.
Relax!
Happy 2016! You now know what smegma means and what you can do to prevent it. We have never seen a horse with a serious problem due to a dirty sheath. However, a dirty shed attracts more flies that can cause Summer Sores (habronemiasis). It can be difficult to treat summer sores. You should also make sure that you don’t miss other serious conditions such as infection, lacerations, or tumors. Your veterinarian should inspect the sheath every routine vaccine. Also, pay attention to when your horse urinates. This will allow you to look for any unusualities.
You will have something to say at cocktail parties or lunch, if nothing else.