Why do we clean sheaths in geldings:

The sheath in a gelding is a place where the penis resides when not in use. In geldings there is no natural way of it being cleaned because they no longer use it for reproduction. If a penis shaft is not used for reproduction there will be a build up of excess dead skin and cellular material over time. This can lead to urethral beans developing and if they become big enough they can obstruct the outflow of urine from the tip of the penis.

Problems that can be found in the sheath and on the penis:
  • Urethral beans
  • Infections and irritations caused by dead skin on the shaft of the penis
  • Skin cancer in the form of squamous cell carcinoma
  • Sarcoids
  • Melanomas
Urethral beans:

These are usually cream coloured and can be stone like in consistency. They are a build up of smegma (dead skin cells and grease) that lodge at the tip of the penis. They can get quite large and can in the worst cases cause a blockage to urine leaving the penis. This in turn can cause problems (if not noticed) to the bladder and in the worst case the kidneys. It is important that these are removed when seen.

Infections and irritations:

These are commonly seen in the spring and autumn/winter months. The penis appears red and swollen, the dead skin looks like thin paper sheets hanging off the penis shaft. In some cases flies can use these affected areas to lay eggs and maggot or fly strike is a common sequelae.

Skin cancer:

The most common form of skin cancer on the penis shaft is Squamous Cell Carcinoma (SCC). This cancer can start off as a raised plaque on a pink shaft but soon starts to eat into the penis tissue. Treatment is removal or the tumours or in the worst of cases full removal of the shaft and the gelding is then rewired to urinate like a mare. If these tumours are caught early there is very little cause for concern but if not then amputation is needed to save the life of the horse


Anywhere a fly can land and bite, sarcoids can occur and this includes the penis. There are different treatments for sarcoids in this area from laser surgery through to amputation depending on the severity of the issue.


These are common in grey horses and can arise anywhere. They are usually slow growing but can get to the size where the gelding is unable to drop his penis from the sheath. This can then mean when he urinates that the urine pools in the sheath and this can lead to infections. Treatment is usually laser to remove the melanomas, or the onset vaccine which shrinks them down. There have been cases where surgical amputation of the penis has been required.

It is important to keep an eye on the sheath and penis for the reasons above. The best way to get a closer look is during a sheath clean which should be done twice a year.

How to clean a sheath:
  • Warm water
  • A clean cloth or cotton wool
  • Gloves

The water should be warm but not too hot – think of a baby’s bath in temperature. Gently get hold of the penis shaft and using the water soaked clean cloth of cotton wool gently wash the shaft until it is clean. Make a not of any lumps or bumps or reddened patches of skin.

If you gelding is shy and less than keen to allow you to touch his penis then getting your vet to sedate and do it for you may be less stressful and easier all round. If you have any further queries please do not hesitate to phone the office on 01782 898102.