Page 1320 - Equine Clinical Medicine, Surgery and Reproduction, 2nd Edition

Skin 1295

VetBooks.ir (30,000 IU/ml p/o q24 h) until resolved can help to DERMATOPHYTOSIS
boost the foal’s local antiviral immune response. As
the interferon is absorbed locally in the oral cavity, Definition/overview
administration 1 hour prior to hay or feed is rec- Occasionally, young foals become infected with
ommended. Benign neglect is also reasonable as the Trichophyton spp. or Microsporum gypseum. Usually
papilloma lesions will often spontaneously resolve the dam is affected, or the foal is immunocompro-
within 3–4 months, especially if the immune sys- mised. Oral interferon alpha (3,000–30,000 IU/ml
tem is not compromised. p/o q24 h) until resolved can help to boost the foal’s
local immune response. As the interferon is absorbed
Prognosis locally in the oral cavity, administration 1 hour prior
The prognosis is good, and most cases resolve to hay or feed is recommended. Exposing the foal to
spontaneously. sunlight and a dry, clean environment away from the
original source of the infection will help to prevent
DERMATOPHILOSIS reinfection and perpetuation of the clinical signs.
Topical chlorhexidine or accelerated hydrogen per-
Definition/overview oxide-based shampoo or spray can be used to hasten
Dermatophilosis is an uncommon disease in young recovery and minimise infection of in-contact foals
foals. It tends to affect foals with long (downy) or horses.
coats stabled under unhygienic conditions and
subjected to higher than normal rainfall and/or PEDICULOSIS
warm humid weather, or foals that are immuno-
logically compromised (Fig. 12.106). Moving the Definition/overview
foal to a dry, clean environment along with topical Foals may contract lice from infested dams or other
chlorhexidine or accelerated hydrogen peroxide- horses in a group, or from contaminated rugs and
based shampoo or spray typically results in resolu- stables.
tion of clinical signs.
STRONGYLOIDES WESTERII AND
PELODERA STRONGYLOIDES
INFESTATION
12.106
Definition/overview
Free-living larval strongyloid worms cause severe
irritation to the limbs of foals.

Aetiology/pathophysiology
Infestation usually only occurs after prolonged wet
weather when foals are kept in old horse yards, on
contaminated straw bedding or under conditions of
poor hygiene.

Clinical presentation
Limb stamping, irritability, pruritus and biting at
limbs are evident. The limbs may swell if contact is
Fig. 12.106 Dermatophilus infection in a 2-week-old prolonged.
Arabian foal with severe combined immunodeficiency.
Note the loss of hair from the head and neck, with Differential diagnosis
typical rain-scald appearance. Stable fly bites; itch mites; poultry red mites; colic.