SYMPTOMS 295 



A more severe type is commonly seen. The cough is fre- 

 quent, more or less painful, the back somewhat arched and the 

 milk secretion diminished. These symptoms increase, the 

 appetite is affected, the animal loses flesh, the breathing 

 becomes more rapid, the cough more painful, pressure of the 

 fingers between the ribs produce evidence of tenderness, the 

 hair loses its gloss and stands erect, the skin becomes adher- 

 ent, the temperature rises to 103 or 105° F. Animals thus 

 affected may continue to grow worse and die in from three to 

 eight weeks or they may after a time begin to improve and 

 make an apparent recovery. The inflammation of the lung 

 does not, as a rule, subside and the organ returns to its normal 

 condition as in ordinary pneumonia, but with this disease the 

 life of the affected portion of the lung is destroyed, the tissue 

 dies and a fibrous wall is formed around it to shut it awaj' 

 from the living parts. The tissue, thus encysted, gradually 

 softens, becomes disintegrated and breaks down into pus. The 

 recoverv, therefore, is onh' partial. 



By those accustomed to examining the lungs of cattle, 

 other and extremely important symptoms may be detected dur- 

 ing the course of the disease. B5' auscultation an area of a 

 certain extent ma\- be found where the natural breathing sound 

 is diminished or entirely lost. This represents the diseased 

 portion of the lung. In other cases a loud blowing sound may 

 be heard, quite different from any sound produced when the 

 lung is in a healthy condition. In some cases crepitation is 

 heard near the border line of the diseased area and friction 

 sounds produced by the roughened pleura may be detected. 

 By percussion an area of dullness may be discovered corre- 

 sponding to the portion where the respiratory murmur has 

 disappeared. This loss of respiration detected by auscultation, 

 and the dullness brought out by percussion are the most 

 important evidences of an area of inflamed or consolidated lung. 



Seriously affected animals remain standing if they have 

 sufficient strength, but those which lie down are said to always 

 lie on the affected side. 



The proportion of animals that become affected after being 

 exposed varies according to the virulence of the outbreak, the 



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