On a horse which sustains chafing from nylon webbing, choose a nylon halter with a padded lining in the crown piece and noseband, or a nylon breast collar lined with felt or fleece. A caveson, pulled tight on a hunt or dressage bridle, might need cushioning to prevent abrasion on the horse's nose or chin. Tack can irritate the skin's surface just because of what it is made from. Metals such as nickel and chromium are contact allergens, with nickel associated with contact dermatitis in humans and dogs. Nickel is an element in bits and other hardware.
Some manufacturers now market nickel-free bits.
However, generations of horses have worn bits of steel and nickel alloys with most showing no ill effects. Dermatologists surveyed on this issue report that no research has shown that nickel bits have caused problems in horses. The condition of an item can cause irritation. A girth with a felt lining acts as a cushion against the skin, yet the fabric becomes stiff and hard when sweat dries. A leather cinch or girth must be kept supple, smooth, and free of salt that abrades the skin.