TUBERCULOSIS 



287 



be noted. By applying the car to the chest wall and listening 

 to the lung sounds, absence of respiratory inni'iinirs and abnor- 

 mal sounds may be distinguished, duo to consolidation of tho 

 lung tissue, abscess cavities and pleural adhesions. In a well- 

 advanced case the hair is rough, the skin becomes tight and the 

 neck thin and lean. The animal may breathe through the mouth 

 when it is exercised. Weakness may be a prominent symptom. 



Breeding animals that are well fed and cared for may live 

 for several years before showing noticeable s\Tnptoms of tuber- 



FiG. 90. — Tubercular spleens. 



culosis. The disease progresses more rapidly in milch cows, espe- 

 cially if given poor care. Calves allowed to nurse a tubercular 

 mother that is giving off tubercle bacilli frequently develop 

 enlarged throat glands and the intestinal form of the disease. 



Hogs develop a generalized form of tuberculosis more quickly 

 than cattle, but an unthrifty, emaciated condition is seldom 

 noted in hogs under ten months old. 



Post-mortem Lesions. — The effect of the tubercle bacilkis 

 on the body is to irritate and destroy the tissues. Lumps or 

 tubercles form in the l;)Tnphatic glands, liver, lungs, spleen (Fig. 



