CHAPTER IX. 

 ANTHRAX. 



THE disease of cattle known as anthrax or "splenic 

 fever" is of infrequent occurrence in this country and in 

 England. In France, Germany, Hungary, Russia, Persia, 

 and the East Indian countries it is a dreaded and common 

 malady which robs herdsmen of many of their valuable 

 stock. Siberia perhaps suffers most, the disease being so 

 exceedingly common and malignant as to deserve the 

 name "Siberian pest." Certain local areas, such as the 

 Tyrol and Auvergne, in which it seems to be constantly 

 present, serve as distributing foci from which the disease 

 spreads rapidly in summer, afflicting many animals, and 

 ceasing its depredations only with the advent of winter. 

 It seems to be distinctly a disease of the summer season. 



The animals most frequently affected are cows and 

 sheep. Among our laboratory animals white mice, 

 guinea-pigs, and rabbits are highly susceptible ; dogs, 

 cats, most birds, and amphibians are almost perfectly 

 immune. White rats are infected with difficulty. Man 

 is only slightly susceptible, the manifestation of the dis- 

 ease as seen in the human species being different from 

 the same disease in the lower animals in that it is usually 

 a local affection malignant carbuncle and only at times 

 gives rise to a general infection. 



Anthrax was one of the first of the specific diseases 

 proven to be caused by a definite micro-organism. As 

 early as 1849, Pollender discovered small rod-shaped 

 bodies in the blood of animals suffering from anthrax, 

 but the exact relation which they bore to the disease was 

 not pointed out until 1863, when Davaine, by a series of 

 interesting experiments, proved to most unbiased minds 



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