Pastern Dermatitis / Scratches: FAQ

By Dr. Richards

Information for the many of you that are dealing with Equine Pastern Dermatitis (aka Scratches/Mud Fever). It can be found in the “Files” section of this page.

‘Tis the season… For lots of concern about problems with the skin on the lower legs of our horses.
Equine Pastern Dermatitis (EPD), along with its accompanying pseudonyms and causes, is emerging all around us as we deal with the end of winter mud and the damp spring mornings. EPD is multi-factorial and often difficult to get a handle on. However, it is important to get it under control as it is very irritating to our equine companions and the potential of severe complications can be career or life ending for our beloved mates if we do not. Your first step should be to work with your vet to identify the condition and potential causes with your horse, in your specific situation.

Treating for Chorioptic mites is usually recommended, particularly with feather-legged horses, to take
them out of the mix as you move forward with other treatments. This requires topical treatment with an appropriates miticide (insecticide) and involves treating over a 2 ½ months, applied as appropriate for the selected product, because mites can live in the environment for 69 days off of the host. (Since the Chorioptes mite is a biting mite, systemic insecticides are not effective.) Anything that you can do to reasonably treat the environment may be helpful. And you do want to treat all of the horses in a living area at the same time. (Even though you may not see signs on other horses, they are a host for the mites and will re-infect a more sensitive horse.)

Topical treatment for EPD requires clean and dry legs with care given to gently removing crusts or scabs. You may need to clean the leg(s) with a medicated shampoo or other keratolytic product. At that point treatment can vary based upon what products you and your vet prefer. A topical treatment product or product mix will often include a soothing product with antiseptic properties (like zinc oxide, silver sulfadiazine, etc.) along with adding a topical corticosteroid, as well as antibacterial and antifungal compounds. Your vet may have different or additional recommendations, including the possibility of a systemic antibiotic and more, tailored to your horse and situation. Treating the EPD can take some time, so stay the course until the it is resolved.

Below is a list of resources that will provide more information to give you diagnostic and treatment
ideas for EPD along with information on potential complications.
EQUUS Magazine – Quick and easy scratches relief
Belmont Farm and Equine Vets – Vet Services
The Horse – Getting a Handle on Scratches in Horses
Kentucky Equine Research – Pastern Dermatitis in Horses: Causes and Care
The Horse – What’s New in Treating Pastern Dermatitis
The Horse – Equine Pastern Dermatitis: A Pathologist’s Perspective
UC Davis Center of Equine Health – Chronic Progressive Lymphedema (CPL)
The Horse – Why Does My Horse Have a Fat Leg?

“Copyright© Nanci LM Richards, DVM and Horse Vet Corner. Do not reproduce or alter without
permission from the author and/or HVC.”