What is it?
Pastern Dermatitis is an inflammatory condition of the skin involving the lower limbs, particularly non pigmented skin. Organisms that most commonly cause Pastern Dermatitis include fungi, bacteria and mites in horses with feathering at their fetlocks.
How does this occur?
A number of environmental conditions can predispose the horse to Pastern Dermatitis, however those horses with white limbs and feathering at the fetlock appear to be particularly susceptible. Conditions that are favourable to the development of Pastern Dermatitis, by reducing the effectiveness of the skin as a barrier to organisms, include;
- Constant exposure to moisture (swimming, wet bedding, muddy paddocks)
- Low heel conformation
- Insect bites on the lower limb
- Abrasions from loose surfaces (gravel/sand)
What does it look like?
Early in the disease, Pastern Dermatitis appears as a mild dermatitis with swelling and reddening of the back of the pastern. Hind limbs tend to be more frequently involved; however lesions can occur on all four limbs. With progression of the disease, numerous scabs and/or crusts may form, causing matting of the hair.
If left untreated the infection may extend up the limb and secondary infection may occur, resulting in lameness and more severe swelling of the limb. In horses with feathering at the fetlock, lesions tend to be more severe and occur over a larger area, whilst lesions tend to be smaller in short haired horses.
How do I treat pastern dermatitis?
The most important aspect of the treatment involves identifying and removing the predisposing factor(s) that started the disease. Once the predisposing factor(s) are removed, steps to reduce and treat Pastern Dermatitis include:
- Keep lower limbs dry
- Clip hair (Usually required in horses with feathering) and clean the affected areas
- Soak the affected limbs for 10 minutes with water
- Remove all scabs with a soft cloth, but DO NOT cause bleeding as this will lead to further scab formation. Scabs may need to be softened before removal using chlorhexidine solution or an iodine soak to prevent this. Once softened, remove scabs by rubbing lightly with either an iodine or chlorhexidine solution, or medicated shampoo.
- Once removed, hose off solution with water and towel dry
- Apply antiseptic ointment over affected region daily as required
Does the condition require veterinary attention?
If Pastern Dermatitis is found in its early stages, the above steps should be followed. If the lesions worsen even with treatment, or any severe signs such as lameness, cracking or bleeding are present, you should seek veterinary advice. The veterinarian may need to assess the horse to direct appropriate therapy such as antibiotics.