ANTHRAX 



91 



disease naturally. The more common anatomical changes, 

 except in the most acute cases and in the strictly localized 

 lesions or carbuncles are: (i) Hemorrhages varying in 

 amount from petechiae to blood extravasations, with more or 

 less serous, gelatinous and hemorrhagic infiltration of the 

 submucous, subserous and subcutaneous tissue ; (2) Enlarge- 

 ment of the spleen with parenchymatous inflammation of the 

 liver and kidneys; (3) A dark tar-like condition of the 

 blood ; and (4) The presence in the tissues and blood of 

 Bacterium anthracis. In the very acute cases these changes 

 are often slight, while in the more chronic forms they are 

 strongly marked. It is important to note that occasionally 

 the usual changes indicated by the symptoms and the duration 

 of the disease are not found on post-mortem examination. In 

 one epizootic, the writer has seen an animal dead from sub- 

 acute anthrax in which the blood and tissues were teeming 

 with anthrax bacteria, yet the organs appeared to be perfectly 

 normal. Other animals in the same outbreak exhibited the 

 more usual anatomical changes. 



The blood is usually ver}' dark and tar-like in appearance. 

 The cutaneous capillaries are distended and frequentlj^ there are 

 hemorrhages beneath the epidermis. The subcutis is sprinkled 

 with ecchymoses. Frequently there are gelatinous effusions 

 of a rather firm consistance and of varying size. The color 

 also differs, ranging between a deep yellow and a yellowish 

 brown. Often these oedematous areas are sprinkled with 

 hemorrhagic foci. A simple serous oedema may occur. 



The lymphatic glands may be hemorrhagic or oedematous 

 or both. Frequently an oedematous condition of the connective 

 tissues of the neck or about the trachea is very marked. 



The muscles vary in color but usuall}' they are darker 

 than normal, and like the skin, they often become sprinkled 

 with ecchymoses. The heart muscle suffers from parenchy- 

 matous changes (myocarditis). 



In the larger cavities of the body, a sanguinolent fluid is 

 found in moderate quantities. Blood extravasations of differ- 

 ent sizes are seen under the serous membranes, particularly on 

 the mesentery and mediastinum. The subserous connective 



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