South African Equine Veterinary Association Congress 2015 Protea Hotel Stellenbosch
Permethrin
Ivermectin (oral )
Treat contact horses and environment!
Treatment failure
Other
Agent didn‟t reach the parasite
Clip
Remove crusts
Contact animals not treated
Environment not treated
How about the rest of the body?
causes
of
Pastern
dermatitis:
Immune mediated - Vasculitis
Usually restricted to the white part of the lower limbs and muzzle –even if other parts
of the body are non-pigmented
Suggest a local environmental substance like pasture plants causes photo-activated
contact dermatitis
Histopathological findings include leukocytoclastic vasculopathy
Photodermatitis
Phototoxicity/ solar -/ actinic dermatitis: classic sunburn reaction due to dose
related response to UV light
Photosensitivity: occurs when skin has increased susceptibility to damaging effects
of UV light because of production, ingestion or injections of a photodynamic agent
Photocontact dermatitis: most common caused by contact to certain plants
Treatment :
Avoidance of sunlight (pasture access at night), bandages on lower limbs
Identification and elimination of cause
Symptomatic treatment of liver disease
Steroids (topical and/or oral)
If present treat secondary infections
Removal of crusts (Dr. Keith Brown‟s remedy : Scarlett oil, chlorhexidine ,
miconazole)
Most
severe
Form
Chronic progressive lymphedema:
of
Pastern
dermatitis:
Progressive swelling, hyperkeratosis and fibrosis of distal limbs
Shires, Clydesdales and Belgian Draft horses, (Gypsy Vanners)
Starts at an early age and progresses to disfigurement
Closely resemble a condition known in humans as chronic lymphedema or
elephantiasis nostras verrucosa
Lower leg swelling caused by abnormal functioning of the lymphatic system in the
skin, results in chronic lymphedema (swelling), fibrosis, decreased perfusion
subsequent secondary infections of the skin
Characterized by skin thickening,
crusting and possible skin folds in the pastern area
Readily palpable, not appreciated
because of heavy feathering
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