Greasy heel attacks the lower leg, usually in the fold of skin at the back of the pastern, just above the heels. There are horizontal fissures and a dry crust over red, ulcerated and exudative skin. These lesions are very painful to the touch. A weeping, inflamed sore quickly spreads, and is highly contagious to other horses.
A form of non specific bacterial and or fungal infection which is similar to thrush is in its list of predisposing factors - including poor diet, filthy stables, a damp environment, or humid conditions of any sort. For example, well fed and cared for race horses will get it because they are worked and wet every morning, and if the legs are not towelled off correctly, they take a long time to dry in winter. The draught horse is also predisposed as the feathers hold heat and moisture close to the skin. The initial infection can lead to chronic, painful dermatitis of the back of the pastern.
The best prevention is to clean and dry the legs thoroughly every time you wet the horse. Use disposable paper towels.
Equipment that will be re-used, should be washed daily, and dried in the sun to prevent spreading the bacteria to other horses.
Treatment involves improved hygiene and management. Wash the affected area thoroughly with iodine scrub and remove all the scabs until the area is pink and clean. Dry thoroughly and clip off excess hair. Treat with specific, commercially available treatments or try a 5% copper sulfate solution, or a zinc sulphate solution (refer to thrush). A fungal cream combined with an antibacterial cream makes a good ointment. Use disposable paper towels and for drying, and wash your hands thoroughly.
The infected horse should be last on the list for grooming, and touch the infected leg, (if only one), last of all.
Please note that occasionally, what looks like bacterial dermatitis or greasy heel, may be due to vasculitis, photosensitisation, (caused by plant toxins and/or liver disease), or a fungal infection etc. Therefore, if your horse does not respond to topical treatments, hygiene, and diet changes, the condition warrants veterinary investigation.