MICROBIAL DISEASES OF MAN AND DOMESTIC ANIMALS 805 



the formation of spores. If buried too near the surface, the rise of 

 the ground water, or the castings of earth worms, bring spores to 

 the surface and on to the herbage, where they may be ingested by graz- 

 ing animals. Tanneries using anthrax-infected hides may be the cause 

 of distributing the organism by means of effluent water which has been 

 used for steeping hides. Many such cases have been traced in Dela- 

 ware, Wisconsin and in Ontario. Hay from an infected pasture may be 

 transported to a distant farm, and cause an outbreak of the disease. 

 In Brazil, vultures feeding on anthrax carcasses disseminate the spores 

 by means of their excrement, and thus spread the disease. Blood- 

 sucking flies may also be instrumental in transferring the bacterium 

 from one animal to another. 



. Season is a contributing factor. In years in which the spring 

 floods have been very high, followed by a hot dry season, anthrax is 

 most prevalent. 



There are a few preliminary symptoms; there is usually sudden 

 loss of appetite, trembling and convulsive movements. Often blood 

 is seen in urine or faeces or discharged from the nose. The mucous 

 membranes are often bluish in color, and boils or pustules may occur 

 on various parts of the body. Death in cattle occurs in two to five 

 days and in sheep in twenty-four to thirty-six hours. The mortality 

 is high and intestinal cases are fatal in 80 to 90 per cent of the animals 

 attacked. 



The usual post-mortem appearances are enlargement of the spleen, 

 blood thick and tarry, bloody extravasations in the muscles and organs, 

 and bloody fluids escaping from mouth, nostrils or anus. 



In anthrax-infected districts vaccination should be used. The 

 vaccines are prepared by cultivating the bacterium at a high tempera- 

 ture 42 to 43 thus forming an asporogenous race, according to 

 methods devised by Pasteur in 1881. Two vaccines are often 

 used, the first of very low virulence, the second more virulent. 

 Between 1882 and 1907, 8,000,000 sheep and 1,300,000 cattle have been 

 vaccinated in France against anthrax, with excellent results. Vaccina- 

 tion by toxin has been advocated by Toussiant, Hawkin, Marmier 

 and others, but this method has not had the success of that described 

 above. 



For treatment of the disease in man, Sclavo's serum has been of 

 considerable benefit. This serum is obtained from the sheep or ass. 



