DISEASES OF THE RESPIRATORY ORGANS. 115 
quent, beating from fifty or sixty to eighty or more a minute. There 
is usually a dry cough from the beginning, which, however, changes 
in character as the disease advances; for instance, it may become 
moist, or if pleurisy sets in, the cough will be peculiar to the latter 
affection ; that is, cut short in the endeavor to suppress it. In some 
cases the discharge from the nostrils is tinged with blood, while in 
other cases it has the appearance of muco-pus. The appetite is lost 
to a greater or less extent, but the desire for water is increased, par- 
ticularly during the onset of the fever. The membrane within the 
nostrils is red and at first dry, but sooner or later becomes moist. The 
legs are cold. The bowels are more or less constipated, and what 
dung is passed is uually covered with a slimy mucus. The urine is 
passed in smaller quantities than usual and is of a darker color. 
The animal prefers to have the head where the freshest air can be 
obtained. When affected with pneumonia a horse does not lie down, 
but persists in standing from the beginning of the attack. If pneu- 
monia is complicated with pleurisy, however, the horse may appear 
restless and lie down for a few moments to gain relief from the 
pleuritic pains, but he soon rises. In pneumonia the breathing is 
rapid and difficult, but when the pneumonia is complicated with 
pleurisy the ribs are kept as still as possible and the breathing is 
abdominal; that is, the abdominal muscles are now made to do as 
much of the work as they can perform. If pleurisy is not present 
there is little pain. To the ordinary observer the animal may not 
appear dangerously ill, as he does not show the seriousness of the 
ailment by violence, as in colic, but a careful observer will discover 
at a glance that the trouble is something more serious than a cold. 
By percussion it will be shown that some portions of the chest are 
less resonant than in health, indicating exclusion of air. If the air 
is wholly excluded the percussion is quite dull, like that elicited by 
percussion over the thigh. 
By auscultation important information may be gained. When the 
ear is placed against the chest of a healthy horse, the respiratory 
murmur is heard more or less distinctly, according to the part of the 
chest that is beneath the ear. In the very first stage of pneumonia 
this murmur is louder and hoarser; also, there is a fine, crackling 
sound something similar to that produced when salt is thrown in a 
fire. After the affected part becomes solid there is an absence of 
sound over that particular part. After absorption begins one may 
again hear sounds that are of a more or less moist character and 
resemble bubbling or gurgling, which gradually change until the 
natural sound is heard announcing return to health. 
When a fatal termination is approaching all the symptoms be- 
come intensified. The breathing becomes still more rapid and diffi- 
cult; the flanks heave; the animal stares wildly about as if seeking 
