ngs in some diseased conditions.
For example, when fluid collects in the air passages and the air is
forced through it or is caused to pass through tubes containing
secretions or pus. Such sounds are of a gurgling or bubbling nature and
are known as mucous rales. Mucous rales are spoken of as being large or
small as they are distinct or indistinct, depending upon the quantity of
fluid that is present and the size of the tube in which this sound is
produced. Mucous rales occur in pneumonia after the solidified parts
begin to break down at the end of the disease. They occur in bronchitis
and in tuberculosis, where there is an excess of secretion.

Sometimes a shrill sound is heard, like the note of a whistle, fife, or
flute. This is due to a dry constriction of the bronchial tubes and it
is heard in chronic bronchitis and in tuberculosis.

A friction sound is heard in pleurisy. This is due to the rubbing
together of roughened surfaces, and the sound produced is similar to a
dry rubbing sound that is caused by rubbing the hands together or by
rubbing upon each other two dry, rough pieces of leather.

THE EXAMINATION OF THE DIGESTIVE TRACT.

The first point in connection with the examination of the organs of
digestion is the appetite and the manner of taking food and drink. A
healthy animal has a good appetite. Loss of appetite does not point to a
special diseased condition, but comes from a variety of causes. Some of
these causes, indeed, may be looked upon as being physiological.
Excitement, strange surroundings, fatigue, and hot weather may all cause
loss of appetite. Where there is cerebral depression, fever, profound
weakness, disorder of the stomach, or mechanical difficulty in chewing
or swallowing, the appetite is diminished or destroyed. Sometimes there
is an appetite or desire to eat abnormal things, such as dirty bedding,
roots of grass, soil, etc. This desire usually comes from a chronic
disturbance of nutrition.

Thirst is diminished in a good many mild diseases unaccompanied by
distinct fever. It is seen where there is great exhaustion or depression
or profound brain disturbance. Thirst is increased after profuse
sweating, in diabetes, diarrhea, in fever, at the crises of infectious
diseases, and when the mouth is dry and hot.

Some diseases of the mouth or throat make it difficult for the horse to
chew or swallow his feed. Where difficulty in this respect is
experienced, the following named conditions