into play. These muscles, especially in
the region of the flank, are seen to contract, then pause for a moment,
then complete the act of contracting, thus making a double bellowslike
movement at each expiration, a sort of jerky motion with every breath.
The double expiratory movement may also be detected by allowing the that
the expiratory current is not continuous, but is broken into two jets.
When the animal is exerted a wheezing noise accompanies the breathing.
This noise may be heard to a less extent when the animal is at rest if
the ear is applied to the chest.

As before remarked, indigestion is often present in these cases. The
animal may have a depraved appetite, as shown by a desire to eat dirt
and soiled bedding, which he often devours in preference to the clean
feed in the trough or manger. The stomach is liable to be overloaded
with indigestible feed. The abdomen may assume that form called
"potbellied." The animal frequently passes wind of a very offensive
odor. When first put to work dung is passed frequently; the bowels are
often loose. The animal can not stand much work, as the muscular system
is soft. Round-chested horses are said to be predisposed to the disease,
and it is certain that in cases of long standing the chest usually
becomes rounder than natural.

Certain individuals become very expert in managing a horse affected with
heaves in suppressing the symptoms for a short time. They take advantage
of the fact that the breathing is much easier when the stomach and
intestines are empty. They also resort to the use of medicines that
have a depressing effect. When the veterinarian is examining a horse for
soundness, and he suspects that the animal has been "fixed," he usually
gives the horse as much water as he will drink and then has him ridden
or driven rapidly up a hill or on a heavy road. This will bring out the
characteristic breathing of heaves if the horse is so afflicted, but
will not cause the symptoms of heaves in a healthy horse. All
broken-winded horses have the cough peculiar to the affection, but it is
not regular. A considerable time may elapse before it is heard and then
it may come on in paroxysms, especially when first brought out of the
stable into the cold air, or when excited by work, or after a drink of
cold water. The cough is usually the first symptom of the disease.

_Treatment._--When the disease is established there is no cure for it.
Proper attention paid to the diet will