What is greasy heel in horses?
Greasy heels refer to a wide variety of equine skin reactions, primarily caused by an infectious agent called Dermatophilus congolensis, which thrives in muddy wet conditions. Correctly referred to as metacarpal dermatitis, mud fever is often called “fatty heels” or “cracked heels” and is frustratingly common in rainy weather.
Why do horses get greasy heel?
The infection can go numb on the skin, becoming active when the skin is compromised, usually by prolonged wetting. Spores germinate and produce hyphae (filiform tentacles) that penetrate the skin and spread in all directions from the original site. This case, an acute inflammatory reaction. Equine skin provides an ideal medium for various bacterial organisms, as well as fungi and other parasites. These microorganisms live on healthy skin, gaining nutrition from natural waste matter and causing no damage or active infection.
But, if the skin is injured or damaged – by a cut, wound, bite, seize wound, or prolonged wetting – the balance between the host and the body is disturbed. The organism enters the horse’s body through the broken skin and multiplies in the hot, moist epidermal layers, from an active infection.
How do horses get greasy heel?
Some types of soil seem to predispose horses to these infections. This may explain why several animals in the same pasture become affected.
There are several other predisposing factors:
- Prolonged moist, mild conditions.
- Standing in the deep mud or dirty bed.
- Constantly washing members before and/or after work, without drying them completely after.
- Excessive sweat under carpets or tack.
- Heavy fringed limb is often accused, but this is probably just because the legs tend to be washed and rubbed more than the featherless ones; clipping them out may not be the answer, as this exposes the skin even more.
- Trauma of the skin, such as from friction boots stretch or bandages incorrectly assembled, rubbed from artificial surfaces, such as sand, or preparation of excess enthusiasm.
- Generally unhealthy skin or the presence of a deficient immune system, usually secondary to some other primary health problem.
- White limbs or spots on the body, possibly due to an associated photosensitization problem.
Some horses with pastern dermatitis will be suffering from infestations of tiny chorioptic mange mites, similar to those that cause human mange. This is more common in horses with long hair around their lower limbs, but it can occur on less hairy legs. The condition is often called heel scabies. Yeast infections can also be responsible for damage to the skin.
Signs of Greasy Heal in Horses                         Â
The signs of mud fever are quite classic and easy to recognize, with the distribution of injuries that reflect the areas that have undergone continued watering and trauma.
- Tangle areas of hair containing crusted crusts
- Small, circular, ulcerated, wet lesions under scabs
- Thick, creamy, white, yellow, or green discharge (Containing the causal organism) between the skin and overlying scabies
- Scab removed typically has a concave bottom with protruding hair roots
- Deep cracks in the skin – in severe cases, the skin on the back of the leg can split open, producing the horizontal cracks that are characteristic of cracked heels
- Eventual hair loss leaving the skin raw, inflamed underneath
How to Treat Greasy Heel in Horses?
Keeping the skin clean and dry is the basis for treating the condition. This can only be possible if the horse is removed from the wet and mud and kept locked up.
The more specific treatment has to penetrate the causal organisms under the scabs, so they must be lifted and removed initially. The horse may have to be sedated for this, as it can be excruciating. Some of the harder scabs may need to be dipped or poulticed first to soften them before they can be peeled off.
Once the area is free of scabs, it must be washed – using a mild disinfectant such as chlorhexidine, iodine wash or surgical scrub, or another medical shampoo – and then thoroughly washed.
Drying the limb entirely is vital – towels or kitchen paper can be used to wipe away moisture, and a hairdryer is an excellent way to completely dry the area if the horse allows it. Once dry, there are numerous creams, lotions, and emollients that can help. Zinc, castor oil, lead acetate, and various commercial anti-inflammatory ointments can play a role, but only if the skin is clean and dry underneath.
