FAMILY I. MYCOBACTERIACEAE 



705 



Med., 23, 1925, 569; and others). Furth 

 (Jour. Immunol., 12, 1926, 273) and Shaffer 

 (Jour. Path, and Bact., 40, 1935, 107) on this 

 basi.s divided Mycobacterium avium into 1 or 



2 subgroups. 



Distinctive characters: Tubercle bacilli 

 pathogenic for fowls but not for guinea pigs 

 or rabbits; culturally distinguished from 

 the mammalian types by the absence of 

 pellicle formation in fluid media and the 

 habit of growth on most solid media; anti- 

 genically distinguished from other species. 

 Source: Isolated from tubercles in fowls; 

 widely distributed as the causal agent of 

 tuberculosis in t>irds and less frequently in 

 pigs- 

 Habitat: The cause of tuberculosis in 

 chickens. Transmissible to pigeons, other 

 birds, mice, rabbits and pigs. 



12. Mycobacterium paratuberculo-sis 



Bergey et al., 1923. (Darmtuberculose bacil- 

 len, Johne and Frothingham, Deutsch. 

 Ztschr. f. Tiermed., 21, 1895, 438; Pseudo- 

 tuberkulose bacillen. Bang, Berl. tierarztl. 

 Wochschr., 22, 1906, 759; Bacillus of Johne's 

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

 20, 1907, 48; also see Twort, Proc. Roy. 

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

 1st ed., 1923, 374; Mycobacterium enteritidis 

 Lehmann and Neumann, Bakt. Diag., 7 

 Aufi., 2, 1927, 755; Bacterium paratuberculo- 

 sis Meissner and Berge, in Kolle and Wasser- 

 man, Handbuch d. path. Mikroorganismen, 



3 Aufl., 6, 1927-29, 788; Mycobacterium 

 johnei Francis, Jour. Comp. Path., 53, 1943, 

 140.) 



pa.ra.tu.ber.cu.lo'sis. Gr. pref. para 

 beside, related; M.L. noun tuberculosis 

 tuberculosis; M.L. fem.n. paratuberculosis 

 tuberculosis-like, paratuberculosis. 



Common name: Johne's bacillus. 



Description taken from M'Fadyean (op. 

 cit., 1907, 48) and Twort and Ingram (A 

 Monograph on Johne's Disease, London, 

 1913). 



Plump rods, 1 to 2 microns in length, 

 staining uniformly, but occasionally the 

 longer forms show alternately stained and 

 unstained segments. Non-motile. Acid-fast. 



This organism is difficult to cultivate, 

 and, in primary cultures, it has been grown 

 only in media containing dead tubercle ba- 



cilli or other dead acid-fast bacteria (Bo- 

 quet, Ann. Inst. Past., 37, 1928, 495). In a 

 few instances cultures have been acclima- 

 tized to a synthetic medium free from added 

 dead bacteria (Dunkin, Jour. Comp. Path, 

 and Therap., ^6, 1933, 159; Watson, Canad. 

 Pub. Health Jour., 26, 1935, 268). 



Colonies on glycerol agar containing heat- 

 killed Mycobacterium phlei: After 4 to 6 

 weeks, just distinguishable, dull-white, 

 raised, circular. 



Colonies on Dorset's glycerol egg medium 

 containing heat-killed M. 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 irregularly folded and dull 

 yellowish white. 



Dorset's glycerol egg medium containing 

 sheep's brain and heat-killed M. phlei: 

 Growth slightly more luxuriant than that 

 described immediately above. 



Glycerol broth containing heat-killed M. 

 phlei: Thin surface pellicle which later be- 

 comes thickened and folded. 



Dorset's synthetic fluid containing heat- 

 killed M. phlei: Growth as in glycerol broth 

 with Mycobacterium phlei. 



Pathogenicity: Produces Johne's disease, 

 chronic diarrhoea, in cattle and sheep. Ex- 

 perimentally produces a similar disease in 

 bovine animals, sheep and goats. Guinea 

 pigs, rabbits, rats and mice are not affected. 

 Very large doses in laboratory animals pro- 

 duce slight nodular lesions comparable with 

 those pi'oduced by M. phlei. 



Antigenic structure: Johnin, prepared as 

 is 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 reaction may be produced in 

 animals sensitized to avian tuberculin and 

 that avian tuberculin causes a reaction in 

 some animals infected with Johne's bacillus. 



Distinctive characters: Small acid-fast 

 bacilli which produce characteristic lesions 

 in cattle; grow only in the presence of dead 

 acid-fast bacilli. 



Comment: The organism isolated from a 

 similar disease in sheep is probably identi- 



