Bacteria, fungi and viruses can all cause skin infections in horses and ponies. The following describes the most common types. If you suspect your horse is suffering from a skin infection you should consult your veterinary surgeon.
This is one of the most important skin diseases of horses found throughout the world. Several species of fungus can cause it but Trichophyton equinum, Trichophyton mentagrophytes and Microsporum equinum are most common.
The disease is spread by direct "horse to horse" contact or indirect spread via communal grooming equipment and tack. Young horses are more susceptible due to lack of previous exposure and hence immunity. Resistance does develop after exposure but due to the fact there are several fungal species responsible and that immunity is not life-long, re-infection can occur. Ringworm is a highly zoonotic disease, which means it is transmissible to humans.
Lesions are most commonly found in the saddle, girth and neck areas. They are localised, often circular and consist of areas of hair loss with reddening of the skin, flaking and scab formation. Occasionally lesions may be itchy.
A hair sample or skin scraping is required and the fungus responsible is cultured or visualised under a microscope.
The infection will clear up by itself in 1-3 months but it is best treated due to its contagious nature. Topical antifungal creams are available as well as systemic antifungals that are placed in your horse’s feed or given as an oral paste. Treatments are usually given for 1 week.
This causes rain scald on the back regions and mud fever in the pastern/fetlock areas. These conditions are especially seen in the autumn/winter following prolonged or heavy rain and can spread to any horses which are in contact.
Thick scabs. These can be secondarily infected.
Loss of hair.
Keep inside.
Remove the scabs daily, wash with disinfectant shampoo, dry then apply topical antibiotics.
This condition does have a tendency to recur.
These can be due to strangles infection or wounds.
Initially the lesion may be hot and painful and then later can be "walled off."
Your veterinary surgeon will decide whether it is necessary to surgically remove an abcess.
This is an inflammation of the hair follicle.
The lesions are often in places in contact with tack.
Wash the tack/brushes in an antiseptic solution.
Wash skin lesions in antiseptic shampoo.
Antibiotics may be required.
In general these diseases cannot be treated although Papillomas may be removed surgically. They are diagnosed by biopsy although viral arteritis can be diagnosed using serology (i.e. from the blood) or it can be isolated from the respiratory tract.
These are caused by a papovavirus (transmitted by flies).
Grey-white flat warts are found on the inner surface of the ear.
Attempts can be made to control the spread by using fly repellents, fine meshes and stabling the horse at dusk.
This is caused by pox viruses.
Grey-white pimples with a waxy surface are found on the penis, prepuce, mammary glands, thighs, axilla and muscle.
This is caused by pox viruses.
Round pimples with crusts and associated hair loss.
Isolate the horse.
Small warts found especially on the head of young horses.
They usually drop off after 3-4 months.
This is caused by a virus called a togavirus.
Pimples and a rash will be seen.
Other signs include abortion or infertility and systemic signs such as fever, depression, panting and being unwilling to exercise.
If you suspect your horse has any of these conditions, you should contact your veterinary surgeon as soon as possible.