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COMMON DISEASES. 



mistaken for tuberculosis. The lung" symptoms, as seen on ex- 

 amination postmortem, vary so much that it is rather difficult to 

 describe them. Sometimes the lungs resemble those seen in ordi- 

 nary broncho-pneumonia. In other cases considerable areas of 

 the lung tissue is changed to a gray mass, soft to the touch. In 

 still other cases there are developed distinct abscesses. 



FIG. 45. ACTINOMYCOSIS— LUMPY JAW. (M. H. R.) 



Note the enlarged jaw and the raw, granulating tissue exposed. 



This disease is usually of slow development. A small swell- 

 ing appears somewhere about the head, perhaps under the tongue ; 

 or the bones of the face near the teeth begin to bulge slightly out- 

 ward and the enlargements continue very slowly. The animal 

 may remain thrifty for a long time or indeed until the disease in- 

 volves the teeth, tongue or other organs and interferes directly 

 with nutrition. 



Prevention. — There is so little known concerning the life 

 history of the parasite and the methods of infection that a study 

 of prevention can be only partially satisfactory. It is generally 

 agreed that animals develop lumpy- jaw only after inoculation, i. e., 

 -the germs find entrance through some cut or scratch in the skin ; 



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