RESPIRATORY APPARATUS. 113 



■exists. Therefore, when appreciable irritations (rales) are 

 present, unaccompanied by cough, the prognosis is an unfavor- 

 able one. 



The character of the cough. The character of the 

 cough varies with the species of animal. Healthy horses have 

 a strong, vigorous, loud, fuU-toncd cough; cattle a sharper 

 defined, softer, toneless, prolonged cough, the glottis being 

 held open. The appearance of cough in animals is always ab- 

 normal; its character depends upon the disease which causes 

 it. Whether cough accompanies the disease or not can usuallv 

 be learned from the anamnesis, although we can not depend 

 upon this to determine its character. It is always best that we 

 induce the patient to cough in our presence ; this may be done 

 by pincEng the upper three rings of the trachea or pressing 

 the finger ends of both hands against the arytenoid cartilages 

 of the larynx. In sensitive healthy horses one or a few short 

 coughs will follow the manipulation, while in indolent indi- 

 viduals there is no reaction. In the ox coughing can be in- 

 duced in this way only when the" animal is diseased. 



If the ox can be made to cough by pinching the upper 

 trachea or larynx, or if coughing takes place in the horse 

 when only slight pressure has been used, some abnormal irri- 

 tation exists. If cough can be readily induced by pressing 

 the lower windpipe, a tracheitis is present. 



The frequency of the cough. A cough may 

 be occasional or frequent, continual or transitory. If the 

 cough is occasional usually only one or a few impulses occur, 

 but when frequent several in succession — a fit of coughing. 



The p a i n f u I n e s s of the cough is recognized' by the 

 general behavior of the patient which seeks to suppress the 

 pain by shaking the head and making masticatory and swal- 

 lowing movements. The animal may also be restless, paw 

 and groan. A painful, painless, burdensome, and torturing 

 cough may be distinguished. The cough is painful in acute 



