Mud fever, also known as scratches or pastern dermatitis, is a group of diseases of

horse The horse (''Equus ferus caballus'') is a domesticated, one-toed, hoofed mammal. It belongs to the taxonomic family Equidae and is one of two extant subspecies of ''Equus ferus''. The horse has evolved over the past 45 to 55 million yea ...

s causing irritation and dermatitis in the lower limbs of horses. Often caused by a mixture of bacteria, typically '' Dermatophilus congolensis'' and ''

Staphylococcus ''Staphylococcus'' is a genus of Gram-positive bacteria in the family Staphylococcaceae from the order Bacillales. Under the microscope, they appear spherical ( cocci), and form in grape-like clusters. ''Staphylococcus'' species are faculta ...

'' spp., mud fever can also be caused by fungal organisms (

dermatophyte Dermatophyte (from Greek '' derma'' "skin" ( GEN ''dermatos'') and ''phyton'' "plant") is a common label for a group of fungus of ''Arthrodermataceae'' that commonly causes skin disease in animals and humans. Traditionally, these anamorphic (a ...

s).

Photosensitization Photosensitizers produce a physicochemical change in a neighboring molecule by either donating an electron to the substrate or by abstracting a hydrogen atom from the substrate. At the end of this process, the photosensitizer eventually returns to ...

, chorioptic mange mites, contact dermatitis, and other conditions also contribute to some cases. This condition is also known as dew poisoning, grease, grease heel, or greasy heel.

Cause

Mud fever is caused by an infection of the skin by bacteria, including ''Dermatophilus congolensis'', and often ''Staphylococcus'' spp. Dermatophytes (fungal organisms such as '' Malassezia'' or ''

Trichophyton ''Trichophyton'' is a genus of fungi, which includes the parasitic varieties that cause tinea, including athlete's foot, ringworm, jock itch, and similar infections of the nail, beard, skin and scalp. Trichophyton fungi are molds characterize ...

'') can also contribute, as can chorioptic

mange Mange is a type of skin disease caused by parasitic mites. Because various species of mites also infect plants, birds and reptiles, the term "mange", or colloquially "the mange", suggesting poor condition of the skin and fur due to the infectio ...

mites. Photosensitivity or irritant contact may contribute in certain cases. Rarely,

vasculitis Vasculitis is a group of disorders that destroy blood vessels by inflammation. Both arteries and veins are affected. Lymphangitis (inflammation of lymphatic vessels) is sometimes considered a type of vasculitis. Vasculitis is primarily caused ...

can cause continued inflammation.

References

{{reflist

External links

VetSci
– Mud Fever Infographic
ArcaNatura
– Guide to Visually Diagnosing Clinical Signs of Scratches Horse diseases

Cause

See also

References

External links