ISO 



BACILLUS OF HOG ERYSIPELAS. 



Pasteur (1883). 



SYNONYMS. SCIIWEINEKOTHLAUF (Germ.}', ROUGET (Fr.). 



Origin. In the blood, internal organs, etc., of swine infected 

 with the disease. 



Form. Very small, narrow rods resembling needle-shaped 

 crystals. Are usually single, but may occur in pairs and even in 

 threads. 



Motility. Has motion. 



Sporulation. Spore formation is not known. 



Anilin Dyes. Stain readily. Gram's method gives excellent 

 results. 



Growth Is rather slow. 



Growth. On gelatin plates the colonies are very characteristic and ap- 

 pear as diffuse cloudy patches which are sometimes difficult to see. Little 

 or no surf are growth. No liquefaction 



Stick Cultures. In gelatin are likewise very characteristic. The growth 

 develops along the line of inoculation as a delicate, cloud-like radiating col- 

 umn. As the culture becomes old a depression forms at the top, due to slow 

 liquefaction and corresponding evaporation. .Sometimes liquefaction can 

 be observed. 



Streak Cultures. On agar and on blood- serum it forms a scarcely visible 

 thin film or group of colonies. No growth on potatoes. 



Bouillon. A very delicate diffuse cloudiness forms which can best be 

 seen on slight agitation. Resembles the bouillon culture of the Tetanus 

 bacillus. 



Oxygen requirements. Is a facultative aerobe. Best growth 

 under anaerobic conditions. 



Temperature. Grows slowly at ordinary temperature. Best 

 at 36 C. 



Behavior to Gelatin. Does not perceptibly liquefy gelatin. 



Aerogenesis Produces hydrogen sulphide in pure cultures, 

 and in the body. This gas is also produced by the anaerobic bac- 

 teria and to a less extent by nearly all pathogenic bacteria. 



Attenuation Old cultures become attenuated and this re- 

 sult can also be obtained by growing the virulent germ at high tem- 

 peratures, about 42 C.,for*some time (Pasteur). 



Immunity. By inoculation with attenuated cultures first 

 and second vaccine of Pasteur perfect immunity can be produced. 

 One attack of the disease confers immunity. 



Pathogenesis. Swine, rabbits, pigeons, white mice, house mice 

 'are susceptible, while guinea-pigs and chickens are insusceptible. 

 Bacilli distributed throughout the organism ; are single or in pairs, 

 and very often can be seen to be enclosed in cells. 



Infection. Probably occurs naturally in swine through the 

 food. 



