By far the most common mite affecting horses is Chorioptes. These mites tend to affect the legs of horses with plenty of feather. They cause irritation which is commonly manifested by stamping of the hind limbs, chewing of the forelimbs and rubbing the legs on each other or on the stable / fenceposts. Badly affected horses often have thickened
skin and scabs, particularly around the pasterns. Some horses develop bleeding sores and secondary bacterial infection can cause lameness and swollen legs.
Other species of mite can occasionally cause itchiness and skin lesions elsewhere on the body such as the face and neck.
The clinical signs of itchy legs in a horse with feathers is usually enough to make a diagnosis, but brushings of the hair can be taken for microscopic examination if required.
Lesions elsewhere on the body may be subjected to a skin scrape to obtain samples for examination under the microscope.
There are no licensed treatments available. Many horses with feather will never be completely free from mites so it is more a case of keeping the condition to a level where it is not causing a significant problem. Our advice on treatment is as follows:
For mild cases:
Clip feather off once a month, wash legs in Hibiscrub or Seleen (to remove dirt and grease from the skin and keep secondary bacterial infection at bay), use shavings bedding and clear it all out monthly after clipping and washing the legs. Treat any scabs or lesions with antiseptic cream such as Dermisol.
Adding an “anti-itch” supplement to the feed such as Dodson & Horrell Itch Free may help to reduce irritation and self trauma. The old fashioned remedy of Flowers of Sulphur in Pig Oil applied every few days often helps although it can be very messy to use.
For severe cases:
There are a variety of treatments available which are prescription only medicines. We need to examine the horse to confirm the diagnosis and advise on the most appropriate treatment which could include injections, special washes or sprays. Antibiotic creams may be required to treat secondary bacterial infection.
Long term management of affected horses:
Turn out as much as possible (But look out for mud fever if the legs are clipped and the ground is wet and muddy). You may need to use an antiseptic barrier cream .
Use a shavings bed (or medicated bed such as Easi-Bed or Nedz Bed Pro) and clear out the bedding regularly. Clip the feathers off all legs once monthly if you can do.