Other lower leg ailments and lymphatic diseases
An over-production of keratin common in feathered horses. It is often worse behind the knee (“mallenders”) and infront of the hock (“sallenders”) because of the flexion of the joints causing the dried out keratin to crack. There is no cure but routine application of a good quality, quickly absorbed emollient will help prevent the build up that leads to the skin drying out and cracking. It needs to be kept under control or it will become infected or scar which can lead to lymph pooling above and below.
Primary and secondary lymphoedema
Primary lymphoedema is a result of a genetic problem where the lymphatic system does not fully or correctly form during gestation.
Secondary lymphoedema is the result of extrinsic factors such as injury, trauma, infection (such as lymphangitis or cellulitis).
Typically affecting only one or both hind or fore legs (not all four legs) and fairly common in all breeds.
Image credit Zoie Morrow
Cellulitis is a bacterial infection of the soft connective tissue. It is also known as “leg blow up” or “septic cellulitis”. If not treated quickly enough, it can lead to secondary lymphoedema.
Image credit Michelle Spencer
Inflammation of the lymphatic system commonly caused by bacterial infection. There are three types of lymphangitis: Sporadic, Ulcerative and Epizootic.
Epizootic lymphangitis is a rare but notifiable disease in the UK.
It is important to note that cultures may initially be negative, especially in the case of Ulcerative Lymphangitis and should be repeated. If not treated properly it can lead to secondary lymphoedema.
Image credit Tracy Pratt
Primary Most common cause is exposure to clover grazing, affecting the muzzle and distal limbs. Also St John’s Wort, buckwheat, rye grass, alfalfa.
Secondary hepatogenic. Systemic, liver disease.
May affect only the white/unpigmented areas (hence quite common on pasterns) or the whole body.
Image credit Calm Healthy Horses
Mud Fever / Scratches / Greasy Heel
Arguably the most common form of exudative pastern dermatitis, affecting all types of horses. Mud fever is so called because it’s associated with wet, muddy turnout conditions which damage the skin and let bacteria in, causing infection. Commonly associated with but not limited to non-pigmented areas of feathered pasterns. Skin scrape and targeted treatments to avoid it developing into cellulitis. Streptococcus spp., dermatophilus congolensis, may also be fungal.
Image credit The Scottish Farmer
Pastern Leukocytoclastic Vasculitis
Affecting the blood vessel walls of the distal limbs resulting in dermacated circular, crusted, exudative lesions of non-pigmented areas. Leukocytoclastic vasculitis can affect the whole body.
Image credit Pool House Equine Clinic
Suspected to involve a localised defect of keratinisation affecting the epithelium in immuno-compromised equines, the prognosis unfortunately is very poor. These photos show the progression over several years. For more information visit this page.
Image credit Randall Honey
Significant cause of pastern dermatitis. Chorioptic mange, chorioptes spp. Intensely puritic. If untreated can lead to self-injury and damage to the tissue and superficial lymph vessels.
Chronic Progressive Lymphoedema 