Equine Sarcoids: What They Are and How to Manage Them

What Are Sarcoids in Horses?

Sarcoids are the most common type of skin tumour in horses, donkeys, and mules. Sarcoids are made up of abnormally dividing fibroblasts, a type of cell that forms connective tissues such as collagen. These tumours are generally benign but can be locally aggressive and recurrent.

Horses can develop sarcoids on any part of their body, however they are most commonly seen in the head, groin, armpit and chest areas. They can also appear on locations where the skin has been previously injured.

There are six different types of Sarcoids that may be seen on your horse, these include:

1. Occult Sarcoids: These are flat, hairless, and often mistaken for ringworm or other skin conditions.

2. Verrucous Sarcoids: Wart-like in appearance, often with a rough surface.

3. Nodular Sarcoids: Firm, round, and typically found under the skin, often in clusters.

4. Fibroblastic Sarcoids: Fleshy, ulcerated, and often bleed easily.

5. Mixed Sarcoids: Exhibit characteristics of two or more types.

6. Malevolent Sarcoids: Highly aggressive, spreading rapidly and invading surrounding tissues

Common Causes of Equine Sarcoids

Sarcoids are caused by Bovine Papilloma Virus (BPV). Whilst BPV originates in cattle, it can be spread to horses through the saliva of biting insects. Sarcoids are not believed to be directly contagious between horses.

Sarcoids can affect any horse of any age, however occurrence seems to be more common in geldings and horses with a weakened immune system.

How to Diagnose Sarcoids on Horses

If you suspect your horse has sarcoids, it is important to contact your vet. A vet can determine the specific type of sarcoid/s and can advise on the most appropriate course of treatment if needed. In some cases, a vet may want to carry out a biopsy to confirm a diagnosis.

Sarcoid Treatment Options for Horses

Thankfully, there are several treatment options available for horses with sarcoids. Many sarcoids will remain unchanged for years and some will even resolve on their own. The treatment method will ultimately depend on the type of sarcoid and where they are located on the body.

Surgical Removal of Equine Sarcoids

A scalpel is used to remove the sarcoid, this procedure is normally done under sedation. Horses will normally require stitches following surgical removal. There is a high risk of recurrence involved with this method as surrounding tumour cells are often missed.

Laser Treatment for Sarcoids in Horses

A laser is used to vaporise the sarcoid and tumour cells, this reduces the risk of regrowth. This is often a less invasive procedure with a quicker recovery time.

Cryotherapy for Treating Sarcoids

Involves freezing the sarcoid with liquid nitrogen. This method often requires several treatments to fully remove the sarcoid.

Ligation Technique for Removing Sarcoids

Involves wrapping a tight band around the sarcoid, this process cuts off the blood supply eventually causing the sarcoid to fall off.

Immunotherapy for Equine Sarcoids

A relatively new approach to treating sarcoids that involves injecting the sarcoid and surrounding area with immune stimulants. This triggers the immune system to identify and attack the tumour cells.

Topical Treatments for Horse Sarcoids

Can be applied directly to the sarcoid. There are many topical treatments available; each of these will work in a different way.

Radiotherapy as a Sarcoid Treatment Option

Involves exposing the sarcoid and the surrounding area to radiation. This works by damaging the tumour cells and preventing them from spreading further.

Several studies have shown that the recurrence rate of sarcoids following treatment is high, so it is important to continue monitoring your horse’s body for any changes that could indicate further incidences of these, even if treatment is successful.

How to Prevent and Manage Sarcoids on Horses

While sarcoids can’t always be prevented, there are steps you can take to reduce risk and support your horse’s health:

1. Boosting Immune Health to Reduce Sarcoid Risk

A strong immune system can help horses fight off viral infections more effectively. A diet which includes antioxidant ingredients like nettles, rosehip, turmeric and clivers helps support the flushing of toxins, while astragalus, echinacea and ginger can support immune function.

2. Controlling Flies to Prevent Equine Sarcoids

• Since BPV is spread by biting flies, reducing exposure is essential:

  • Use fly sprays and fly rugs to deter insects.

  • Avoid grazing in marshy and waterlogged areas.

  • Add garlic to your horse’s diet—this natural fly deterrent is a key ingredient in Revive ’n’ Shine skin & coat supplement.

3. Hygiene Practices for Managing Sarcoids in Horses

• Keep your horse’s environment clean to prevent flies from breeding.
• Monitor for skin injuries and treat wounds promptly.
• Regularly inspect your horse’s coat for new lumps or changes in existing sarcoids.

Final Thoughts on Sarcoid Treatment and Prevention

Sarcoids can be frustrating to deal with, but early detection, proper treatment, and ongoing management can help keep them under control. If you notice any suspicious skin changes, contact your vet as soon as possible. The sooner a sarcoid is addressed, the better the chances of preventing complications and recurrence.

By staying informed and proactive, you can help your horse stay comfortable, healthy, and happy—even if sarcoids become part of their life.