FAMILY PARVOBACTERIACEAE 



557 



gie, 6th ed., 2, 1913, 743; Nocardia lig- 

 nieresi Chalmers and Christopherson, 

 Ann. Trop. Med. and Parasit., 10, 1916, 

 242; Discomyces lignieresi Brumpt, Pre- 

 cis de Parasitol., Paris, 3rd ed., 1922, 

 993; Pasteurella lignieresi Vuillemin, 

 Encj^clopedie Mycologique, Paris, 2, 

 Champignons Parasites, 1931, 136.) 

 Named for Lignieres, who first worked 

 with this organism. 



Bacterium purifaciens Christiansen 

 (JVIaanedsskr. f. Drylaeger, 29, 1917, 

 449; Pasteurella purifaciens Hauduroy 

 et al., Diet. d. Bact. Path., 1937, 322) is 

 regarded as identical with this organism 

 by Tunnicliff (Jour. Inf. Dis., 69, 1941, 

 52). 



Rods: 0.4 bj'^ 1.0 to 15.0 microns. 

 Cocco-baciDary forms frequent. Non- 

 motile. Gram-negative. 



Gelatin: Growth sparse or fails. No 

 liquefaction. 



Agar: Primary cultures usually suc- 

 ceed best when the inoculum is intro- 

 duced by stab. Serum agar is more 

 favorable than plain. Surface colonies 

 are small, bluish, translucent at first, 

 later becoming opaque. 



Broth : Serum favors growth. Freshly 

 isolated strains usually grow in form of 

 small granules which adhere to sides of 

 tube, leaving broth fairly clear. Later 

 most strains grow diffusely, often form- 

 ing a fragile pellicle. 



Litmus milk: Most strains cause no 

 change. Sometimes slight acid. No co- 

 agulation. 



Potato : Little or no growth. 



Acid but no gas within 48 hours from 

 glucose, fructose, galactose, maltose, 

 sucrose and mannitol. Acid after longer 

 incubation from lactose, raffinose and 

 glycerol. 



Indole is formed in small amounts. 



Nitrites not produced from nitrates. 



Aerobic. Is favored by increased 

 CO2 tension. Will not grow anaerobi- 

 cally. 



Optimum temperature 37 °C. 



Pathogenic for cattle and swine. A 



few cases reported in man. Rabbits and 

 guinea pigs slightly susceptible to inocu- 

 lation. 



Source and habitat : Usually isolated 

 from the lesions of actinobacillosis of 

 cattle. This condition is often clinically 

 diagnosed as actinomycosis. Lesions 

 found in soft tissues, usually lymph 

 nodes, where granulomatous tumors are 

 formed. Eventually these break down 

 to form abscesses. 



2. Actinobacillus actinomycetemcomi- 

 tans Topley and Wilson. {Bacterium 

 actinomycetem comitans Klinger, Cent, 

 f. Bakt., I Abt., Orig., 1912, 198; Actino- 

 bacillus actinomycetem comitans Topley 

 and Wilson, Princip. of Bact. and 

 Immun., 1, 1931, 256; Topley and Wilson, 

 ibid., 2nd ed., 1936, 279.) From 

 actinomycete, and Latin comitans, ac- 

 companying. 



Description taken from Topley and 

 Wilson {loc. cit.), Colebrook (Brit. 

 Jour. Exp. Path., 1, 1920, 197), and 

 Bayne-Jones (Jour. Bact., 10, 1925, 

 572). 



Cocco-bacilli : Rods 1.0 to 1.5 microns 

 long, cocci 0.6 to 0.8 micron in diameter. 

 Occurring in densely-packed masses. 

 Non-motile. Gram-negative. 



Gelatin: No liquefaction. 



Agar colonies: Small, tough, adherent. 



Glucose agar: Growth thin, dry, gran- 

 ular, hard, slightly yellow, adherent. 



Liquid gelatin or broth : At 37°C, nu- 

 merous isolated, translucent granules, 0.5 

 to 1.0 mm in diameter, form along sides 

 of tube. In a few days they fuse into a 

 grayish-white mass, forming ring around 

 tube and pellicle over surface. Later 

 granules become opaque, grayish -white . 



Glucose broth: Turbid. Yellowish 

 flakes. 



Milk: No growth. 



Potato : No growth. 



Acid but no gas from glucose and lac- 

 tose. 



Not pathogenic for laboratory animals. 



No growth at 20°C. 



