Cysts on the Parotid Duct of a Horse

Horses have three pairs of salivary glands, the parotid gland being the largest. The parotid duct is located at the front of the round cheekbone facing the mouth. A cyst, or fistula, of the parotid duct can make a horse miserable.

  1. Causes

    • The cause of a parotid duct fistula is often an injury, such as a bite from another horse, blockage from food that causes a mineral deposit build-up called calculi, or a birth defect, according to "Equine Pathology."

    Identification

    • Saliva drips from a duct that has been injured. There may be swelling. Cysts caused by calculi cause swelling and eventually burst. These cysts can house calculi stones of up to 600 grams in weight.

    Treatment

    • Calculi must be surgically removed. Any cyst of the parotid duct must be surgically drained and closed so that the horse is not at risk of developing an infection.