Page 861 - The Veterinary Care of the Horse

SUNBURN

VetBooks.ir Sunburn can occur when horses are exposed to harmful doses of ultraviolet light. This may

happen during the summer in the UK.

Clinical signs

The soft, relatively hairless areas of pink skin around the nose and muzzle of some horses are
most commonly affected. These have little protective pigment to prevent absorption of the

harmful radiation. The signs are:
• redness

• itchiness and irritation

• formation of small blisters

• swelling and tenderness
• oozing of serum

• crusty scab formation.

These symptoms develop because the absorption of light energy in the surface layers of skin

causes the release of inflammatory mediators called cytokines. These cause plasma to leak
from small blood vessels which then activates a cascade of events leading to inflammation.

Treatment

Treatment involves:

• stabling the horse on sunny days
• gently cleaning the lesions with an antibacterial scrub, e.g. Hibiscrub ®

• applying a soothing gel, cream or ointment; this may contain substances such as aloe

vera, corticosteroid or antibiotic depending on the severity of the reaction

• application of hypoallergenic sun block.

Prevention

On hot sunny days, horses and ponies susceptible to sunburn should:

• be stabled

• have topical sunscreen applied; some of the hypoallergenic sun blocks designed for
children when swimming stick well to the skin and are effective