Mites
Chorioptes equi
Spend entire life cycle on the host, feeding on skin debris most commonly on lower limbs. Affected animals show intense itching with stomping of the feet. Seen more in animals with feathered fetlocks and mainly seen during winter months. The area should be clipped and treated with ivermectin, permethrin etc.
Harvest mite (neotrombicula autumnalis)
Larvae are found in grasses, forests or swamps in the late summer and autumn. Horses that have harvest mite infestation have small papules with a small yellow/red dot (this is the larva). The face, muzzle, lower limbs and belly are most commonly affected.
Diagnosis
Observation of the distinctive appearance.
Treatment
Is self limiting but treatment is usually carried out as horses may be uncomfortable. Permethrin. Any potentially infected forage should be removed from the ground.