No. 4.] CATTLE COMMISSIONERS' REPORT. -n^ 



other cause of the fever ascertained, the animal still be treated as 

 suspicious, and removed from among others ; for if the symptom 

 is due to tuberculosis, the fever shown by the thermometer indi- 

 cates that the disease is active ; that there is a considerable change 

 of tissue going on within the body, and the fair supposition is, 

 that the disease is so much moi'e aggressive at this time as to 

 make the animal a particularly good disseminator of the con- 

 tagious principle. The milk from animals of this sort should 'not 

 be used. 



Auscultation of the Chest. 

 By this is meant a listening at the walls of the chest, that we 

 may hear the noises that are made by the movements of the organs 

 contained within it. This, by veterinary practitioners, is usually 

 accomplished by pressing the ear firmly against the body at vari- 

 ous points over the ribs ; having the animal under examination in 

 as quiet a place as possible. 



The sounds heard in a healthy lung are of two sorts ; first those 

 that are made by the air as it rushes through the air (bronchial) 

 tubes, and called the tubal sound, which is a rough, blowing noise ; 

 and, second, the sound produced by the air as it enters and leaves 

 the air sacs at the ends of the tubes, called the respiratory mur- 

 mur, which is much softer and considerably less distinct than the 

 sound first described. In order that the sounds produced in dis- 

 ease may be appreciated, it will be necessary first to become 

 familiar with those that are to be heard in the healthy chest. For 

 the purposes of this sort of an examination the chest is divided into 

 three equal parts by drawing two imaginary lines across it from 

 before backward. These divisions are called the superior, middle 

 and inferior regions (Figure 1). 



