86 ANTHRAX 



through wounds of the skin and the respirator}' tract. There 

 are, however, many exceptions to these usual methods. 



(i.) Infection through tlie alimentary canal. This is the 

 more common mode of infection in cattle. The resulting 

 disease has been designated b}- various names among which 

 are "intestinal anthrax," "fodder anthrax," "spontaneous 

 anthrax," "internal anthrax," "anthrax fever," and anthrax 

 without external manifestations. In these cases the infecting 

 organisms, either the spores or the bacteria themselves, are 

 taken into the body with food or drinking water. It is stated 

 that the infection takes place in most cases in the small in- 

 testine, the mucosa of which, it is stated, need not necessarily 

 be injured. It is highly probably that the gastric juice 

 destroys most of the bacteria while the free spores are not injur- 

 iously affected by it. In infected districts the spores exist at 

 or upon the surface of the soil and possibly on the blades of 

 grass from which they are easily taken up hy grazing animals. 

 In cases thus infected the specific organism has been intro- 

 duced at some previous time either (a) by the burj'ing of 

 diseased animals in these fields, (b) by the use of infected 

 tannery or slaughter house refuse as fertilizers, (c) by flood- 

 ing from infected streams, or (dj by the bringing of the or- 

 ganism in the droppings of birds or other small animals which 

 have fed upon anthrax carcasses. It is reported that the spores 

 will find their waj- to the surface even when the dead animals 

 have been buried at a considerable depth. There has been 

 some controversy in the writings of Pasteur, Koch and Bol- 

 linger concerning the method by which the spores reach the 

 surface. Pasteur supposed that they were brought by earth 

 worms from the buried carcasses. Koch believed this impos- 

 sible because of the low temperature of the ground at the 

 depth at which the animals are buried. Bollinger has shown 

 experimentally the possibility of Pasteur's views. Karliniski 

 and others have found that the spores of anthrax may be dis- 

 seminated by slugs, insects and larvae which are found on 

 untanned infected skins. 



(2.) Infection through the skin. In animals, this mode 

 of infection occurs less frequently than in man. Anthrax 



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