Bacillus Cholerse Suis. 

 HOG CHOLERA; SWINE-PLAGUE of Billings; SCHWEINEPEST (G?erm.); 



CHOLERA DU PORC, PNEUMO-ENTERITE (Fr.). 



ORIGIN. In the blood, organs and intestinal contents of swine 

 that die of hog cholera. 



FORM. Short, small rods, like those of chicken cholera. On some 

 media, as gelatin, it may form long rods. Occurs single or in pairs. 



MOTILITY. It is actively motile and has several long, wavy flag- 

 ella. Shows no motion in serum or in blood. 



SPORULATION. Not observed. 



ANILIN DYES. At first impart a bi-polar stain, but on sufficient 

 exposure the entire -rod is colored. Not stained by Gram's method. 



GROWTH. Is fairly rapid. 



Plates. In a couple of days colonies develop on gelatin plates. The deep colonies 

 are very small, yellowish-brown and spherical. The surface colonies spread slightly. No 

 liquefaction. 



Stab culture. Shows along the line of inoculation a white line or row of colonies, 

 while on the surface of the gelatin a thin, very slowly spreading growth forms. 



Streak culture. On agar forms a moist grayish-white growth, without any special 

 characteristics. On potato a straw-yellow growth develops, resembling somewhat that of 

 glanders. 



Bouillon. Diffuse cloudiness of the liquid; a partial film forms on the surface. Indol 

 and phenol are not formed. Milk. Is not coagulated. 



OXYGEN REQUIREMENTS. It is a facultative anaerobe. 

 , TEMPERATURE. Grows well at ordinary temperature. Best at 37. 



BEHAVIOR TO GELATIN. Does not liquefy. 



AEROGENESIS. Glucose is fermented. 



ATTENUATION. Artificial cultures retain their virulence quite 

 well. The virulence can be readily increased Jby repeated passage 

 through rabbits. It is then very fatal to pigeons. 



IMMUNITY. Can be produced experimentally by inoculation with 

 filtered cultures; with repeated small doses of blood, previously 

 heated to 54-58, from infected rabbits (?)> Blood serum of immun- 

 ized animals protects. 



PATHOGENESIS. Hogs, mice, rabbits and guinea-pigs are highly 

 susceptible; pigeons are less susceptible, while chickens, sheep and 

 calves are immune. % c.c. of bouillon culture injected subcutane- 

 ously into rabbits kills in about four days. Bacilli distributed every- 

 where. White necrotic areas in the liver. Hemorrhagic infiltrations 

 are common. 



INFECTION. Results through the food. The 'hog is the only ani- 

 mal that naturally contracts the disease. 



DIAGNOSIS. As a rule the bacillus can be isolated from the heart- 

 blood -and organs. In chronic cases, because of secondary infection, 

 diverse bacteria may be present. . Isolation may be facilitated by 



inoculating a rabbit with the suspected material. 



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