DISEASES OF THE KESPIRATOBY 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 elidted 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 



