Equine dermatophilosis
Definition
• It is self limiting disease of equine caused by
dermatophilus conglensis, characterized by
moist exudative dermatitis and lesion appear as
tufts of matted hair and crust over the shoulder
and back
Etiology
• Dermatophilus conglensis live in crust or scab
from infected animal for 42 m
• Predisposing factors:
▫ Change in atmospheric temperature and humidity
or prolonged skin wetness
▫ Trauma and concurrent disease
▫ Biting insect
Epidemiology
• Distribution: It is worldwide distributed and
reported in Egypt.
• Animal susceptibility: horse, donkeys and mules
• Mode of infection
▫ Source of infection; crust or scabs from infected
animals
▫ Mode of transmission; invasion of organism
through cutaneous wound or abrasion, through
contact with infected animal and spread
mechanically by stable fly (stomoxys) and house
fly (musca domestica)
Pathogenesis
• Following infection, under normal condition, the
stratum cornium is an effective barrier against
infection, but when the resistance of skin was
lowered, the organism penetrate deeply and
invade living dermis inducing an acute
inflammation or exudative dermatitis
Clinical signs
• In long haired horses;
▫ There are large plaques of matted hairs and crusts
which cover a moist gray to pink indurated surface
• In short haired horses;
▫ There are multifocal nodules covered with crusts
or scales in size of 1 to 2.5 mm
▫ The lesion present on muzzle, around eye, distal
extremities and along the back
• In racing horses;
▫ Lesion may present at pastern or fetlock as
numerous scabs adherent to base of hair follicles
with excessive exudation fissures and cracks
resulting in lamness.
Diagnosis
• Direct impression smear for isolation and
identification of the organism
• Isolation of the organism on blood agar, showed
small brown hemolytic colony having rough
texture
Treatment
• Clipping the hair of infected area and remove the
crust
• Local application of .25% chloramephnicol for 57 days
• Systemic antibiotic in generalized cases as
pencillin streptomycin for 3-5 days
• Bandage over pastern and fetlock with
application of creams for neomycin sulfate and
hydrocortisone