FAMILY I. MYCOBACTERIACEAE 



703 



1934. (Bovine tubercle bacilli, Th. Smith, 

 Trans. Assoc. Am. Phys., 11, 1896, 75; also 

 see ibid., IS, 1898, 417; and Jour. Exp. Med., 

 3, 1898, 451; Mycobacterium tuberculosis ty- 

 pus bovinus Lehmann and Neumann, Bakt. 

 Diag., 4 Aufl., 2, 1907, 550; Mycobacterium 

 tuberculosis var. bovis Berge}' et al., Manual, 

 4th ed., 1934,537.) 



bo'vis. L. noun bos the ox; L. gen. noun 

 bovis of an ox. 



Common name: Bovine tubercle bacillus. 



Original description supplemented by ma- 

 terial taken from Topley and Wilson (Prin- 

 cip. of Bact. and Immun., London, 2nd ed., 

 1936, 315). 



Rods which are shorter and plumper than 

 those of the human species. Range in size 

 from 1.0 to 1.5 microns. Very short forms are 

 frequently intermixed with somewhat larger 

 forms. Stain regularly or irregularly. Acid- 

 fast and acid-alcohol-fast. Gram-positive. 



Less easily cultivated than is the human 

 species. 



Glj'cerol agar colonies: Small, irregular, 

 with granular surface; no pigment. 



Dorset's egg, Lowenstein, Petragnani, 

 Woolsey colonies: -Similar to those on glyc- 

 erol agar, but growth is more rapid and colo- 

 nies are somewhat larger. 



For variation in colony structure, see 

 Mycobacterium tuberculosis. 



Glycerol broth: After 8 weeks, thin, gray- 

 white film, slightly nodular; no turbidity; 

 slight, granular deposit. 



Dubos' tween-albumin broth: Growth 

 similar to that of M. tuberculosis. 



Optimum temperature, 37° C. 



Optimum pH, between 5.8 and 6.9 (Ishi- 

 mori, Ztschr. f. Hyg., 102, 1924, 329); be- 

 tween 6.0 and 6.5 (Dernby and Naslund, 

 Biochem. Ztschr., 132, 1922, 392). 



Pathogenicity: Produces tuberculosis in 

 ox, man, monkey, goat, sheep, pig, cat, par- 

 rot, cockatoo and possibl}^ some birds of 

 pre^^ Experimentally it is highly patho- 

 genic for rabbits and guinea pigs, slightly 

 pathogenic for dogs, horses, rats and mice; 

 not pathogenic for fowls. 



Antigenic structure: See M. tuberculosis. 



Source: Isolated from tubercles in cattle. 



Habitat: The cause of tuberculosis in 

 cattle. Transmissible to man and domestic 



animals. More highly pathogenic for ani- 

 mals than is the human species. 



10. Mycobacterium microti Reed, nom. 

 nov. (Vole bacillus. Wells, Lancet, 1, 1937, 

 1221 ; Mycobacterium tuberculosis var. muris 

 Brooke, Amer. Rev. Tuberculosis, 43, 1941, 

 806; Vole tubercle bacillus, Griffith, Jour. 

 Hyg., 4^, 1942, 527; Mycobacterium muris 

 Smith et al., in Zinsser's Textb. of Bact., 

 9th ed., 1948, 483; not Mycobacterium muris 

 Simmons, Jour. Inf. Dis., 41, 1927, 13.) 



mic.ro'ti. M.L. mas.n. Microtus a genus 

 that includes the vole; M.L. gen.noun 

 microti of Microtus. 



Common name: Vole bacillus. 



Description taken from Brooke {op. cit., 

 1941, 806). 



Rods in cultures average 0.4 by 2.5 mi- 

 crons and in tissues, 0.4 by 3.6 microns. 

 Ovoid to spherical forms occasionally occur 

 among the rods. In infected lymph nodes, 

 rods 8 to 10 microns long are occasionally 

 seen. Therefore resembles other mammalian 

 acid-fast species, but in general longer and 

 thinner. Irregular shapes are frequently 

 found in tissues: S-shaped, hook-shaped, 

 semicircular or circular. Acid-fast and acid- 

 alcohol-fast. 



Growth in all media is slow; requires 4 to 

 5 weeks on favorable media before colonies 

 are visible to the naked eye. 



Whole egg medium colonies: After 4 to 6 

 weeks, small, granular, with irregular mar- 

 gins; on further growth the colonies become 

 larger and more irregular. On moist media 

 the consistency is creamj' and on dry media, 

 butyrous to friable. 



Egg yolk-saline medium (3:1) : Growth on 

 this medium is superior to that on Lowen- 

 stein's, Dorset's egg or Dorset's egg plus 

 extract of M. phlei. Growth is enhanced by 

 the addition of 10 per cent CO2 to the at- 

 mosphere. 



Nutrient broth without glycerol: Film- 

 like colonies on the surface: fine deposit. 



Glycerol : Primary growth does not occur 

 on any media containing glycerol. On sub- 

 culture, growth occurs but is not enhanced 

 by the presence of glycerol. 



Distinctive characters: Slow growth, 

 slower than that of the human or bovine 

 forms; growth in nutrient broth without 



