Melanomas

Melanomas are tumours of the skin, which are derived from the pigment-producing cells. They therefore have a heavily pigmented or darkened appearance. They are reasonably common and have a reported incidence of between 4 and 15%. They occur anywhere on the body but are more common in older horses with lighter coats. In fact, in old grey horses, the incidence has been recorded as high as 80%! These tumours are one of the more serious equine skin problems that can initially be benign (unlikely to spread), but eventually, the majority of them develop into malignant tumours and spread.

Squamous cell carcinomas

Squamous cell carcinomas are a type of skin tumour and are reportedly the second most common skin tumour of horses. They most frequently occur in horses between the age of 8 and 14 years but have been found in horses from 1 year old to 29! These equine skin problems are more common in lighter-coloured horses, as sunlight has been implicated as a cause of them. They can occur anywhere on the skin of a horse but are more commonly found on hairless areas such as eyelids, lips, nose, vulva, and prepuce. Early diagnosis is essential, and your veterinary surgeon may even recommend the removal of them to prevent further spread.

Sarcoids

The most commonly diagnosed skin tumour found on horses are sarcoids and have been reported to account for nearly 90% of all skin tumours in horses. Luckily though, they are non-malignant (unlikely to spread) but can invade local tissue and cause irritation to the horse. Also, if they are knocked and bleed, they will attract flies and increase the irritation. Sarcoids can appear in a number of different forms and can look similar to other equine skin problems. It is essential that any lumps are discussed with your veterinary surgeon as soon as they are noticed.

Rain Scald

Rain scald is a bacterial infection of the skin of horses, which causes scabs to form on the back, rump, and lower limbs. These scabs can be easily removed to reveal patches of moist, raw skin. This condition is caused by prolonged wetting of the skin, which allows the bacteria to invade. Equine skin problems like rain scald can be avoided by ensuring the skin remains dry, so stabling the horse or applying a weather-proof rug can reduce the risk of this condition developing. It is important that you contact your Thrums veterinary surgeon for advice on rain scald, as there are a few other conditions that can appear similar.