Equine sarcoids can affect all breeds worldwide

A sarcoid is the most common form of skin cancer in equines and is often not malignant. Three of my horses and ponies have had a sarcoid at some stage. In all three cases they were non maligant and, I’m glad to report, have now gone. Some sarcoids can be difficult to treat and can spread. They are also very nasty when near a vulnerable part of the body, such as the eye, and I would recommend veterinary advice early on. Different horses react in different ways to them and they are a worldwide problem affecting all types of breeds.

My first experience of a sarcoid was many years ago when a thoroughbred developed one on his sheath. It was a small, hard lump and grew quite quickly to about the size of a cherry. I called the vet and she suggested surgery. She removed the sarcoid and sent it to the Equine Laboratory where they examined it and prepared a vaccine which was then given to the horse in two stages. I have read more recently that vaccines against sarcoids are not supposed to work but something worked in this thoroughbred’s case as the sarcoid never regrew. The horse lived to be 30 and never had another one.

An Irish Sports Horse had an enormous sarcoid under his hind leg when a young horse, before I bought him. I know this because I got him from a neighbour next door. This sarcoid was about the size of a tennis ball and was raw and bleeding at times. I don’t know whether the sarcoid was removed by a vet or whether it fell off but it was gone by the time he came to my stables. There is, however, still a scar where it used to be so perhaps it was surgically removed. I’ve had the horse 14 years and he still hasn’t produced another one.

My third sarcoid case was last year when one appeared on a 24 year old pony. At first I thought it might be a melanoma because he is a grey and greys are particularly prone to melanomas but the round hard lump on his sheath grew very rapidly over the summer months and became raw in one place where he rubbed it when lying down. It was about the size of a cherry when I asked the vet about it and she did not recommend surgery because of his age. Vets are reluctant to put older horses and ponies under general anaesthetic unless absolutely necessary. She suggested leaving it alone and said it might fall off. The sarcoid was still there in the winter but not so raw because the flies weren’t irritating it. One day after the winter was over I noticed that it had gone. I was lucky in this case because the sarcoid had fallen off and his sheath is now perfect with no scarring.