Bacillus Indicus, Koch. 



B. RUBER INDICUS. 



ORIGIN. Isolated in India from the contents of the 

 stomach of a monkey. 



FORM. Small, narrow, very short rod with rounded ends. 

 MOTILITY. Actively motile. 

 SPORULATION. Not definitely observed. 

 ANILIN DYES. Stain readily. 

 GROWTH. Is rapid. 



Gelatin plates. Deep colonies are yellowish, with a wavy contour. 

 Surface colonies grayish yellow, finely granular, with fibrillated bor- 

 ders. Show movement of contents, rapidly liquefy and may show a 

 lig-ht pink color. 



Stab culture. Rapid liquefaction along" line of inoculation. 

 Dense flocculent growth settles on the bottom, and is grayish or light 

 pink in color. A delicate scum forms on the surface and is colored 

 from a light pink to a brick red. 



Streak culture. - On agar, it forms a low, moist, spreading" growth 

 which usually is faint pink in color. On potato, the growth is low, 

 not slimy as that of B. prodigiosus, and the color is more marked 

 than on other media. On blood-serum, liquefaction results with, or 

 without pigment production. 



OXYGEN REQUIREMENTS. It grows best in the presence of 

 air, but is a facultative anaerobe. The pigment production 

 depends upon the presence of oxygen. 



TEMPERATURE. The optimum is about 35. The pig- 

 ment is absent in cultures that develop in the incubator. 

 Splendid pigment when growth occurs at 15. 



BEHAVIOR TO GELATIN. It liquefies very rapidly. 



PIGMENT PRODUCTION. Varies greatly. The pigment 

 may be grayish to bright brick-red; lacks the violet tinge 

 of B. prodigiosus. Usually it is light pink, so that the 

 ordinary cultures may be considered as attenuated. 



PATHOGENESIS. It has a marked toxic action, and when 

 Injected in large amounts into the abdominal cavity, or 

 into the veins of rabbits and guinea-pigs, it proves fatal. 

 Rabbits develop marked diarrhea and die in from 3 to 20 

 hours. On post-mortem the intestines show a severe inflam- 

 matory condition of the mucous membrane; at times, 

 ulcerations are present. 



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