DISEASES OP THE RESPIRATORY SYSTEM. 137 



of the disease; at first it is dry, hard, and hacking in character; 

 after a day or two the cough becomes looser and is accompanied 

 by an expectoration, which consists of a frothy mucus, having a 

 yellowish color, and sticky; this expectoration gradually becomes 

 pus-like. After the expectoration is present the animal seems 

 somewhat relieved. 



What are the physical signs? 



In the milder forms of acute bronchial catarrh, where the 

 larger tubes are affected, there may be no special physical signs 

 which can be appreciated. The more severe forms are attended 

 by physical signs that can be readily recognized. 



In the majority of cases, on inspection and palpation, there is 

 nothing to be appreciated. On percussion the sounds are normal 

 in the majority of cases; on account of the thickness of the skin 

 and the hair we are unable, in the horse, to appreciate any change. 

 On auscultation we find the respiratory murmur feeble or somewhat 

 harsh in character. In the dry stage sibilant and sonorous rales can 

 be heard on both sides of the chest. In the second stage, or the 

 stage of secretion, moist rales (large and small) may be heard on 

 both sides of the chest; these moist rales come and go, on account 

 of the mucus changing its position; and, after a violent fit of cough- 

 ing, they may disappear temporarily. 



The auscultatory sounds may be absent at times, so that their 

 absence does not signify that the disease is not present. 



How is the disease diagnosed ? 



Mostly by the physical signs applied to both sides of the chest; 

 on percussion, no appreciable change; on auscultation, sibilant 

 and sonorous rales in the first stage, and mucous rales (large and 

 small) in the second stage; also, the cough and fever aid us aa 

 well as the absence of signs of pneumonia or pleurisy. 



Give the prognosis. 



It is generally good if not complicated. 



What is the treatment ? 



General and local treatment is required. 



Avoid depleting measures, as a rule; stimulation is recom- 

 mended; try to aid discharge from mucous membrane by inhala- 

 tions. 



