Wet Winter Skin Infections: "Scratches & Rain Rot"

It's been a warm, wet, winter this year in most of North Carolina.  These are the kind of winters that cause mud in the pastures and on the trails.  Along with that mud comes fungal/bacterial infections to watch out for in your horse. 

Scratches

"Scratches," a common skin condition in horses, can affect the heel, the back of the pastern, the fetlock, and occasionally the cannon bone. Veterinarians may refer to it as pastern dermatitis or pastern folliculitis. It is also known as "mud fever", "dew poisoning", "greasy heel" or "cracked heels".  It basically looks like a bunch of thick scabs all over your horses lower leg.  Any horse can get scratches but it seems to be more prevalent in white legged horses and horses with feathers such as draft breads. 

 

Severe case of scratches, moving up the cannon bone 

Less severe case of scratches, only affecting the heel

To treat scratches, remember "Don't scratch the scratches!"  Picking the scabs will only make it spread.  Clip hair around the affected area and wash with antibacterial shampoo (chlorhexidine, betadine, or benzoyl peroxide) and let sit for 10 minutes before rinsing.  Do this once a day for about a week and then reduce to 2-3 times per week until resolved.  In severe cases a veterinarian may recommend antibiotic, anti-fungal, or steroid ointments. Prevention is the best method of managing scratches.  Keeping a dry clean environment for your horse and making sure legs are clean and dry after riding/turn-out.  

Rain Rot

"Rain rot", also known as rain scald or dermatophilosis, is a skin infection caused by a bacteria.  Though rain is one risk factor, any form of moisture such as sweating under a blanket can cause the inflammatory infection resulting in lesions along your horse's skin. These lesions cause small patches of raised bumps which are scabs containing clusters of your horse's hair.
While most often found on the horse's top-line, rain rot can be found on numerous areas of the horse's body, including their rump, face, and legs. Unlike many other skin conditions, areas with rain rot do not typically itch but can be painful and cause your horse to become sensitive to touch.  All horses can get rain rot, however horses with lighter coat colors as well as horses with compromised or poorly developed immune systems (such as young or older horses) have been found to be at higher risk. 

  

Rain rot across the back, loin, and croup

Up close view of rain rot lesions

Prevention of rain rot includes regular grooming and maintaining a clean dry environment for your horse.  Make sure to groom after rolling in the mud, especially if there are any open wounds present on your horses back from insect bites, etc.  Be sure to only apply a blanket when it's cold enough (body clipped horses below 60, moderate coat below 40, heavy coat below 30) to avoid sweating.  Treat affected areas with anti-microbial shampoo and currying until resolved.  Severe cases may require antibiotics from your veterinarian.  

For more information visit: Penn State Extension Rain Rot or Perdue Extension Scratches