Sheath cleaning should be performed as a regular part of your gelding or stallion’s preventative health care routine. The “sheath” (or the anatomically correct term, prepuce,) refers to the folds of skin surrounding the penis. These folds and the shaft of the penis accumulate a material called smegma, which is a combination of dirt, oil, sweat and dead skin cells. There is a small pouch near the opening of the urethra which can harbor a “bean,” or an accumulation of smegma, which can range in size from a small pea to as large as a golf ball. The genital area of the horses is one of the most common sites for skin cancer. Smegma has been identified as a carcinogen in several species of animals, including the horse. Regular sheath cleaning is recommended to remove the smegma, and thoroughly examine the sheath and penis for any tumors or pre-cancerous changes in the skin. Smegma accumulation also causes discomfort and is a common cause of tail rubbing. The “beans” can cause discomfort and partial obstruction of urine flow.

Before cleaning the sheath, the horse will be sedated. Besides relaxing the horse, the sedatives also facilitate “dropping,” or extension of the penis out of the sheath for examination and cleaning. Warm water and soft cotton batting is used for cleaning, and a cleanser specifically made for sheath cleaning (which must be rinsed well) if needed. Most horses tolerate this procedure well, and it can be combined with routine dental procedures such as teeth floating. The average gelding needs to have his sheath cleaned once or twice a year while others may need it cleaned more frequently.

Incidentally, mares also develop smegma-like material between the udder and inside of the thigh or between the two halves of the udder. This can also be a cause for discomfort and tail rubbing and can usually be removed with routine grooming.