FAMILY .MYCOB \CTEI{IACEAE 



881 



Habitat : The cause of tuberculosis in 

 chickens. Transmissible to pigeon, other 

 birds, mouse, rabbit and pig. 



3. Mycobacterium paratuberculosis 

 Bergey et al. (Darmtuberculose bacillen, 

 Johneand Frothingham, Deutsch. Ztschr. 

 Tiermed., 21, 1895, 438; Pseudotuberku- 

 lose bacillen. Bang, Berl. tierarztl. 

 Wchnschr., 1906, 759; Bacillus of Johne's 

 Disease, M'Fadyean, Jour. Comp. Path., 

 20, 1907, 48; Twort, Proc. Roy. Soc, B, 

 83, 1910, 156; Bergey et al.. Manual, 

 1st ed., 1923, 374.) From M. L. -para- 

 tuberculosis, of the disease paratubercu- 

 losis. 



Common name: Johne's bacillus. 



The organism from a similar disease in 

 sheep is probably identical though more 

 difficult to cultivate 'Dunkin and Bal- 

 four-Jones, Jour. Comp. Path., J^8, 1935, 

 236). 



Description from M'Fadj^ean {loc. cit.) 

 and Twort and Ingram (A Monograph on 

 Johne's Disease, London, 1913). 



Plump rods, 1.0 to 2.0 microns in length, 

 staining uniformly, but occasionally the 

 longer forms show alternately stained 

 and unstained segments. Non -motile. 

 Acid-fast. 



The organism is difficult to cultivate 

 and, in primary cultures, has only been 

 grown in media containing dead tubercle 

 bacilli or other dead acid-fast bacteria 

 (Boquet, Ann. Inst. Pasteur, 37, 1928, 

 495). In a few instances cultures have 

 been acclimatized to a synthetic medium 

 free from added dead bacteria (Dunkin, 

 Jour. Comp. Path, and Therap., J^6, 1933, 

 159; Watson, Canad. Pub. Health Jour., 

 26, 1935, 268). 



Colonies on ghcerol agar containing 

 heat-killed Mycobacterium phlei: After 

 4 to 6 weeks, just distinguishable, dull- 

 white, raised, circular colonies. 



Colonies on Dorset's glycerol egg con- 

 taining heat-killed Mycobacterium phlei: 

 After 4 to 6 weeks, minute, dull-white, 

 raised, circular, with a thin, slightly 

 irregular margin. Older colonies become 



more raised, radially striated or irregu- 

 larly folded and dull j-ellowish-white. 



Dorset's glycerol egg containing sheep's 

 brain and heat-killed Mycobacterium 

 phlei: Growth slightly more luxuriant. 



Glycerol broth containing heat -killed 

 Mycobacterium phlei: Thin surface pel- 

 licle which later becomes thickened and 

 folded. 



Dorset's sj'nthetic fluid containing 

 heat -killed Mycobacterium phlei: As on 

 glj^cerol broth with M ycobacterium phlei. 



Pathogenicity: Produces Johne's dis- 

 ease, chronic diarrhea, in cattle and 

 sheep. Experimentally it produces a 

 similar disease in bovine animals, sheep 

 and goats. Guinea pigs, rabbits, rats 

 and mice are not infected. Very large 

 doses in laboratory animals produce 

 slight nodular lesions comparable with 

 those produced by Mycobacterium phlei. 



Antigenic structure : Johnin, prepared 

 as tuberculin, gives positive reactions in 

 cattle with Johne's disease. According 

 to M'Fadyean et al. (Jour. Comp. Path, 

 and Therap., 29, 1916, 62) tuberculous 

 animals may also give a reaction. Plumb 

 (Den Kong. Vet. Landboh0jskole 

 Arssk., 1925, 63) has shown that a reac- 

 tion maj' be produced in animals sensi- 

 tized to avian tuberculin and that avian 

 tuberculin causes a reaction in some ani- 

 mals infected with Johne's bacillus. 



Distinctive characters : A small acid- 

 fast bacillus producing characteristic 

 lesions in cattle and growing only in the 

 presence of dead acid-fast bacilli. 



Source : From the intestinal mucous 

 membrane of cattle suffering from chronic 

 diarrhea. Apparently an obligate para- 

 site. 



Habitat : The cause of Johne's disease, 

 a chronic diarrhea in cattle. The bac- 

 teria are found in the intestinal mucosa. 

 Xot pathogenic for guinea pigs or rabbits. 



4. Mycobacterium leprae (Armauer- 

 Hansen) Lehmann and Xeumann. (Ba- 

 cillus leprae Armauer-Hansen, Norsk. 

 Mag. laegevidensk., 9, 1874, 1; Arch, 

 f. path. Anat. u. Physiol., 79, 1879, 



