512 THE CHOLERA GROUP 



Growth on Artificial Media. Gelatin stab cultures are rapidly lique- 

 fied. There is not the "air bubble" appearance which is characteristic 

 of stab cultures of the cholera organism ordinarily. On agar there 

 is a rapidly spreading growth which becomes thick, moist and slightly 

 viscid. Broth is clouded and there is a heavy sediment and a pellicle. 

 Blood serum is rapidly liquefied and milk is coagulated. Acid is 

 formed in dextrose. 



Products of Growth. The nitroso indol reaction is given very slightly, 

 frequently not at all. Indol, however, is produced in large amounts. 

 Proteolytic ferments dissolving gelatin, serum and casein are formed 

 by Vibrio proteus. Cultures have a foul odor. According to Kupria- 

 now 1 levorotatory lactic acid is formed from dextrose. 



FIG. 73. Vibrio metchnikovi, bouillon culture. X 1000. 



Bacteriological Diagnosis. Diagnosis depends upon the isolation 

 of curved organisms resembling the cholera vibrio, which do not 

 react with a cholera immune serum, 



Pathogenesis. Human. According to Metchnikoff, an agar culture 

 eaten by man may result in a slight intestinal disturbance. This, 

 however, probably has no significance. 



Animal. The intraperitoneal inoculation of cultures of Vibrio 

 proteus causes a fatal peritonitis. According to Metchnikoff, 2 by 

 feeding cultures to animals previously treated with sodium carbonate 

 and laudanum to reduce the acidity and intestinal peristalsis, irregular 

 results are obtained. Occasionally a profuse diarrhea results, but it 

 is rarely or never fatal. In pigeons inoculation into the pectoral 



1 Arch. f. Hyg., 1893, xix, 288. 



2 Ann. Inst. Past., 1893, 570. 



