Cervical abscess and pharyngeal fistula in a horse.

A weanling Quarter Horse filly developed ventral swelling of the lower cervical area after difficult passage of a stomach tube for deworming. Intermittent bilateral nasal discharge developed. Radiography revealed fluid and gas density dorsal to the trachea and esophagus. Surgical incision with drainage and debridement of the abscess and fistulous tract, facilitated by use of drains, led to complete recovery. Contrast medium injected after surgery demonstrated a communication between the abscess and the pharyngeal region.