356 INFECTIVE DISEASES. 



Pasteur found that, by successive inoculation of rabbits, the virulence 

 was exalted for rabbits, but attenuated for swine, and the virus 

 which had thus been passed through the rabbit was used as a 

 vaccine for swine, to protect them against virulent erysipelas. 



Pasteur found that by passing the virus through pigeons it was 

 made more virulent for swine. 



In the blood, and the juice of the internal organs, and of the 

 lymph glands, Schiitz found a minute bacillus identical with the 

 bacillus of mouse septicaemia. 



Bacillus of Swine Erysipelas (Schiitz). Extremely minute 

 rods '6 to 1'8 //. in length, morphologically and in cultural charac- 

 ters identical with the bacillus of mouse septicaemia. Filaments 

 and involution forms. Spore-formation present. 



House mice if inoculated with a pure culture die in two to four 

 days. Pigeons are also very susceptible. Fowls and guinea-pigs 



FIG. 142. BACILLI OF SWINE FIG. 143. BLOOD OF PIGEON INOCULATED 

 ERYSIPELAS (BAUMGARTEN). WITH BACILLI OF SWINE ERYSIPELAS, x 600 



(SCHUTZ). 



are immune. Rabbits after inoculation of the ear suffer from 

 erysipelatous inflammation, identical with that produced by inocu- 

 lation of the bacillus of mouse septicaemia. The bacilli are also 

 pathogenic in swine and sheep. 



Protective Inoculation. With Pasteur's vaccine immunity is 

 said to be produced which lasts about a year. Schiitz and Schottelius 

 found the minute bacilli in Pasteur's vaccine, which they had already 

 found in cases of swine erysipelas in Germany. 



The results of vaccination in France are said to be very satis- 

 factory, but in test experiments in Germany they were not so 

 favourable. Out of 119 vaccinated swine. 5 per cent, died as the 

 result of the inoculation, while the average loss in the ordinary way 

 is 2 per cent. 



Metchnikoff found that the blood of immunised rabbits was 

 antitoxic, and Lorenz maintains that the serum of swine which 



