QUESTIONS AND ANSWERS 159 



Describe the post-mortem lesions of anthrax. 



In rapidly fatal cases, changes in the blood and tissues are often 

 so little marked, that, after the engorged spleen and infiltrated 

 internal organs are removed, the carcass appears fit for consump- 

 tion as food. In more protracted cases, the blood is dark, tissues 

 brown or yellow, the heart muscle pale; liver enlarged, soft, pale 

 and hemorrhagic; spleen greatly enlarged or ruptured; lymph- 

 glands hypersemic; serosa peteehiated; the bacterium anthrax is 

 readily demonstrated in blood smears. 



Describe the post-mortem lesions of hemorrhagic septicaemia. 



Widely distributed areas of hemorrhage, varying in size from a 

 pin point to several inches in diameter. Blood extravasations in 

 the subcutem and intramuscular tissues, in the lungs, stomach and 

 intestinal walls, lymph-glands, endocardium, myocardium, and peri- 

 cardial sac. The spleen is usually normal except, perhaps, a few 

 hemorrhagic areas on its surface. The central nervous system may 

 occasionally show hemorrhages, especially in the dura. In animals 

 recently dead, the blood is lighter in color than normal. When 

 decomposition occurs, the blood is black and tarry, but reddens 

 after exposure to the air. Cultures from the tissues reveal the 

 causative factor, bacterium bovisepticus. 



What tissues are most commonly affected by tuberculosis? 



Lungs, liver, intestines, generative organs and the Ijonphatic 

 glands adjoining these organs, especially the mesenteric, portal, 

 mediastinal and those about the head; serous membranes — peri- 

 toneum, pleura, meninges and synovial. 



Describe a miliary tubercle. 



The term "miliary tubercle" was originally applied to tubercles 

 which approximated in size a millet seed, but now is applied to 

 various sizes of new-formed tuberculous nodules, larger or smaller, 

 which show a central necrotic mass of one or more giant-cells sur- 

 rounded by a proliferation of epitheloid cells and outside of this a 

 collection of lymphocytes. It appears as a gray, translucent body 

 and, in properly stained specimens, the tubercle bacillus may be 

 seen. As the central necrotic mass increases in size, it becomes 

 caseated or calcified and a connective-tissue stroma of a fibrous 

 nature may encapsulate the lesion; it then becomes an old, yellow, 

 or crude tubercle. 



