FAMILY V. BRUCELLACEAE 



399 



103) recently reported biochemical methods 

 by which P. pestis and P. pseudotuberculosis 

 can readily be differentiated: on ordinary 

 urea (Difco) slants with phenol red as 

 indicator, the former does not affect the 

 medium whereas the latter produces a red 

 coloration of the medium; with desoxj'cho- 

 late citrate agar, the colonies of P. pestis 

 are rather scant, reddish and pin-point in 

 size after 48 hours at 37° C, while those of 

 P. pseudotuberculosis are abundant, large, 

 opaque and, like the medium in general, 

 become yellow. 



Source: Isolated from buboes, blood, 

 pleural effusion, spleen and liver of infected 

 rodents and man; also from sputum in pneu- 

 monic plague and from infected fleas. 



Habitat: The causative organism of 

 plague in man and in rats, ground squirrels 

 and other rodents. Infectious for mice, 

 guinea pigs and rabbits. Transmitted from 

 rat to rat and from rat to man by the in- 

 fected rat flea. 



6. Pasteurella pfaffii (Hadley et al., 

 1918) Hauduroy et al., 1953. (Bacillus der 

 Kanarienvogelseuche, Pfaff, Cent. f. Bakt., 

 I Abt., Orig., 38, 1905, 276; Bacterium pfaffi, 

 (sic) Hadley, Elkins and Caldwell, Rhode 

 Island Agr. Exp. Sta. Bull. 174, 1918, 169; 

 Pasteurella pfaffi (sic) Hauduroy et al.. 

 Diet. d. Bact. Path., 2" ed., 1953, 377.) 



pfaffi. i. M.L. gen. noun pfaffii of Pfaff; 

 named for Dr. Franz Pfaff of Prague, who 

 isolated this species. 



Description taken largely from Hadley 

 et al. {op. cit., 1918, 180). 



Rods, 0.5 by 1.0 to 2.0 microns, occurring 

 singly. Non-motile. Gram-negative. 



Gelatin colonies: Small, grayish, translu- 

 cent. 



Gelatin stab: No liquefaction. 



Agar colonies: Small, yellowish gray, 

 homogeneous, translucent, entire. No odor. 



Agar slant: Slight, yellowish gray, trans- 

 lucent streak. 



Broth: Turbid; flocculent sediment (Pfaff, 

 op. cit., 1905, 280). 



Litmus milk: Unchanged. 



Potato: Moderate, whitish streak. 



Indole not produced. 



Hydrogen sulfide not produced. 



Acid but no gas from glucose, fructose, 

 arabinose, xylose, maltose, dextrin, salicin 

 and mannitol. Lactose, sucrose, rafiinose, 

 inulin, adonitol and dulcitol not attacked. 



Nitrites not produced from nitrates. 



Aerobic, facultatively anaerobic. 



Optimum temperature, 37° C. 



Pathogenic for canaries, sparrows, pi- 

 geons, white mice, guinea pigs and rabbits. 

 Not pathogenic for chickens (Pfaff, loc. cit.). 



Source: First encountered in an epidemic 

 of septicemia in canaries. Caused a necrotic 

 enteritis. 



Habitat: Not known from other sources. 



7. Pasteurella pseudotuberculosis 



(Pfeiffer, 1889) Topley and Wilson, 1931. 

 (Bacillus pseudotuberkulosis (sic) Pfeiffer, 

 Ueber die bacillare Pseudotuberculose bei 

 Nagethieren, Leipzig, 1889, 5; Streptohacillus 

 pseudotuberculosis rodentium Preisz, Ann. 

 Inst. Past., 8, 1894, 231; Topley and Wilson, 

 Princip. Bact. and Immun., 1st ed., 2, 1931, 

 825.) 



pseu.do.tu.ber.cu.lo'sis. Gr. adj. pseudes 

 false; L. noun tubercnlum a small swelling; 

 M.L. neut.n. tuberculosis tuberculosis; M.L. 

 noun pseudotuberculosis pseudotuberculosis. 



The tabular description by Eisenberg 

 (Bakt. Diag., 3 Aufl., 1891, 294) is very in- 

 complete. Description taken from Topley 

 and Wilson (Princip. Bact. and Immun., 

 2nd ed., 1936, 607) and from Bessonowa, 

 Lenskaja and Molodtzowa (Office Internat. 

 d'Hyg. Publ., 29, 1937, 2106). 



Small rods which vary in size and shape: 

 ellipsoidal or coccoid forms are 0.8 by 0.8 

 to 2.0 microns, with rounded ends, occurring 

 singly; rod-shaped forms are 0.6 by 1.5 to 

 5.0 microns, with rounded ends, occurring 

 singly, in groups or in short chains; occa- 

 sionally long, curved, filamentous forms 

 occur. Motile by means of one to six peri- 

 trichous flagella. Not acid-fast. Gram- 

 negative. 



Gelatin stab: After 7 days at 22° C, good 

 filiform growth extending to bottom of tube. 

 No liquefaction. 



Agar colonies: After 24 hours at 37° C, 

 circular, 0.5 to 1.0 mm in diameter, um- 

 bonate, granular, translucent, grayish yel- 

 low, butyrous; edge entire; dull, finely 



