84 IMMUNITY 



percent. The method requires the employment of two vac- 

 cines made of attenuated anthrax bacilli. No. i is a culture of 

 bacilli attenuated by growing them at a high temperature, 42.5C., 

 in a current of air for twenty-four days. No. 2 is grown at the 

 same temperature for only twelve days. The first vaccine is 

 used to immunize the animal against the second, which causes a 

 marked local reaction, and which is the real immunization agent 

 against infection with virulent anthrax bacilli. The injections 

 are given about one week apart. Many State Governments as 

 well as the Federal Government of the United States supply 

 the vaccine gratis to stock raisers and others. 



Vaccination Against Black-leg or Quarter-evil 



Quarter-evil, or Rauschbrarid, is due to a specific bacillus. 

 Vaccination against this disease may be accomplished by inocu- 

 lating with a powder consisting of dried muscle from the affected 

 part of infected animal. There are two vaccines, No. i, and No. 

 2. The first is prepared by heating (and thus attenuating) the 

 bacilli up to 103 C. The second is prepared by raising the tem- 

 perature up to Q3C. These vaccines are given at a short time 

 apart, and the immunity is effective. The method is valuable 

 to stockmen. 



Vaccination Against Tuberculosis 



There is at present no safe and satisfactory prophylactic meas- 

 ure for the production of increased resistance in man to tubercu- 

 losis. In cattle the repeated injection of bacilli of the human type 

 has been found capable of raising the animal's resisting power to 

 a sort of immunity. The therapeutic use of the various tubercu- 

 lines has on the other hand, met with better success, and it seems 

 that for human medicine at least that they have won a place in 

 the treatment of surgical tuberculosis. They may be also of 

 value in pulmonary disease. 



