884 CLOSTRIDIUM 



Nutritional. — Grows poorly in ordinary media; growth improved by glucose, and 

 by heart extract ; very poor growth in casein digest broth. No growth in bile- 

 salt media. Weak toxin produced. 



Biochemical. — Acid and gas in glucose, maltose, lactose, and sucrose, not in mannitol or 

 salicin. Indole — ; M.R. — ; V.P. — ; nitrate reduction + ; NHg — ; HaS-j- J 

 M.B. reduction — ; catalase — . Litmus milk : variable; sometimes no change ; 

 sometimes sUght acid production, and partial precipitation of casein. 



Antigenic Stnicture. — Appears by agglutination to be serologically homogeneous. Agglu- 

 tinating sera prepared against CI. chauvoei agglutinate this organism, but do not 

 agglutinate CI. septicum except to very low titre. By complement fixation CI. 

 chauvoei and CI. septicum appear to be closely related. Antitoxin is specific, pro- 

 tecting against CI. chauvoei but not against CI. septicum. 



Pathogenicity. — Exotoxin produced. Causes blackleg in cattle, and less often in sheep. 

 Non-pathogenic to man. Experimentally it is fatal to guinea-pigs and less often 

 to mice ; rabbits and pigeons are fairly resistant. 0-25 ml. of a 24-hour culture 

 in Hibler's medium injected intramuscularly kills a guinea-pig in 24 to 48 hours ; 

 p.m. shghtly blood-stained serous exudate at site of injection ; abdominal muscles 

 are deep red and contain numerous small gas bubbles. CI. chauvoei can be recovered 

 from local lesion, peritoneal cavity, and heart blood. 

 (See Kitt 1887, Nocard and Roux 1887, Roux 1888, Kitasato 1889o, 1890, Leclainche 



and Vallee 1900, Eisenberg 1907, Markoff 1911, Landau 1917, Weinberg and Seguin 



1918, Haslam and Lumb 1919, Report 1919, Heller 1920, Goss et at. 1921, Gaiger 1922, 



1924, Hall 1922, Weinberg and Ginsbourg 1927, Weinberg and Mihailesco 1929, Roberts 



1931, Henderson 1932, Kerrin 1934.) 



Clostridium septicum 



Isolation. — Described by Pasteur and Joubert in 1877. 



Synonyms.— B. oedematis maligni, Koch (1881). Vibrion septique, Pasteur. 



Habitat. — Found chiefly in soil. 



Morphology. — Rod-shaped, of variable length and thickness ; on agar cultures, 2-6 /n X 

 0-4-0-6 jU ; sides parallel, ends rounded, axis straight or curved, arranged singly, 

 in pairs, and in short chains. On peritoneal surface of dead guinea-pig it forms 

 long jointed filaments. In tissue exudates and in fluid media containing fresh 

 tissue there are navicular or citron forms with pale swollen bodies and deeper- 

 staining pointed extremities. In agar cultures there is marked pleomorphism ; 

 organisms vary in size, shape, and depth of staining , large numbers of shadow 

 forms are seen. Spores readily formed, and are oval, subterminal, and slightly 

 wider than bacilli ; often found free. Motile by 4-16 peritrichate flagella. No 

 capsule. Gram-positive in young cultures, but often frankly Gram-negative in 

 4 to 5 days. 



Agar Plate. — 4 days at 37° C. Irregularly round, having a general cigarette-in-water 

 appearance, 10 mm. in diameter, effuse, filamentous, translucent colonies, with 

 finely honeycombed surface due to crossing of numerous filaments, and fimbriate 

 edge ; greyish by reflected, bluish-grey by transmitted light ; butyrous and easily 

 emulsifiable. No definite differentiation but filaments are less dense at periphery. 

 Recently isolated strains tend to form continuous spreading films. 



Deep Glucose Agar Shake.- — 4 days at 37° C. Abundant gas formation ; medium 

 disrupted and driven up nearly to plug. Numerous colonies throughout medium, 

 varying in appearance ; most usual type is delicate, arborescent, and flocculent ; 

 sometimes opaque with an irregularly dentate, well-defined edge, from which later 

 woolly filamentous outshoots appear. 



Horse Blood Agar Plates. — 3 days at 37° C. a-prime haemolysis ; after 6 days haemolysis 

 is of /3-type. 



