e discharge is seen dripping from a
small opening. When the discharge from the nostrils has fully developed
the fever usually disappears and the animal regains its appetite, unless
the swelling is sufficient to interfere with the function of the throat,
causing pain on any attempt to swallow. At the end of four or six days
the discharge lessens, the soreness around the throat diminishes, the
horse regains its appetite, and in two weeks has regained its usual
condition. Old and strong horses may have the disease in so light a form
that the fever is not noticeable; they may continue to eat and perform
their ordinary work as usual and no symptom may be seen beyond a slight
discharge from the nose and a rare cough, which is not sufficient to
worry any but the most particular owner. But, on the other hand, the
disease may assume a malignant form or become complicated so as to
become a most serious disease, and even prove fatal in many cases.
Inflammation of the larynx and bronchi, if excessive, produce violent,
harsh coughing, which may almost asphyxiate the animal. The large amount
of discharge may be mixed with air by the difficult breathing, and the
nostrils, the front of the animal, manger, and surrounding objects
become covered with a white foam. The inflammation may be in the lung
itself (lobular pneumonia) and cause the animal to breathe heavily,
heave at the flanks, and show great distress. In this condition marked
symptoms of fever are seen, the appetite is lost, the coat is dry, the
horse stands back in its stall at the end of the halter strap with its
neck extended and its legs propped apart to favor breathing. This
condition may end by resolution, leaving the horse for some time with a
severe cough, or the animal may die from choking up of the lungs
(asphyxia).

The swelling under the jaw may be excessive, and if the abscess is not
opened it burrows toward the throat or to the side and causes
inflammation of the parotid glands and breaks in annoying fistulas at
the sides of the throat and even up as high as the ears. Roaring may
occur either during a moderately severe attack from inflammation of the
throat (larynx), or at a later period as the result of continued lung
trouble. Abscesses may develop in other parts of the body, in the poll,
in the withers, or in the spaces of loose tissue under the arms, in the
fold of the thigh, and, in entire horses, in the testicles.

During the course of the disease, or later,