DESCRIPTION OF SPECIES 



403 



taneous cure. Animals sacrificed 

 after from 12 to 16 days inocula- 

 tion, present lesions more accentu- 

 ated than those sacrificed after yi 

 and 38 days. Inoculated subcu- 

 taneously, pure cultures give rise to 

 small abscess which quickly cures. 

 The organism is non-pathogenic 

 for rabbits and pigeons. 



BUTTER BACIIjIjUS (Grassberger). 



Source and habitat — Butter. 



Morphology — Form, dimensions, 

 manner of grouping. Resembles 

 B. tuberculosis. 



Staining reaction — Ziehl-Neelsen, but 

 loses acid-fast property after some 

 days in culture. 



Biology : cultural characters {includ- 

 ing biochemical features^ 



Bouillon — At 37° C. the liquid 

 becomes cloudy after 24 hours, a 

 veil forms on the surface, later the 

 medium clears, a deposit falls to 

 the bottom of the tube, the veil 

 remains. At 22° C. the medium 

 clouds, no surface veil, a deposit 

 at the bottom of the liquid. The 

 growth is less than at 37° C. 



Glycerine bouillon — This medium 

 is less clouded than ordinary 

 nutrient bouillon. 



Gelatine — Gelatine stab cultures, 

 a faint growth along the needle 

 track. At point of inoculation the 

 growth is dry, wrinkled and of a 

 deep rose colour. Gelatine stroke 

 cultures present a dry, raised, 

 wrinkled growth which does not 

 extend over the surface of the 

 medium ; colour deep rose. No 

 liquefaction. 



Nutrient agar — In stab and 

 stroke cultures, the growth is dry, 

 slightly wrinkled, and extends over 

 the surface of the medium. Rose 

 colour, but lighter than upon 

 gelatine. 



Glycerine-agar — Growth is more 

 granular than upon gelatine, dry, 

 and spreads over the surface of the 

 medium. Colour is not so deep as 

 uf>on gelatine (Plate 25, p. 256). 



Milk — Milk is coloured through- 

 out by the organism, but not 

 coagulated ; thick surface growiih 

 of a deep rose colour, with deposit 

 of same tint. 



Potato — The growth is raised, 

 granular and of a deep rose colour. 

 Apart from colour, resembles the 

 growth of B. tuberculosis on potato. 



BUTTER BACILLUS. No. 1 



(Maria Tobler). 



Source and hcdfitat — Zurich butter. 



Morphology — Form, dimensions, 

 manner of grouping. Morpho- 

 logically resembles B. tuberculosis ; 

 straight or slightly cur^-ed, of vary- 

 ing length. Club-like swellings 

 are of frequent occurrence, and 

 more rarely ramified filaments. 

 The bacilli are often found lying 

 parallel the one to the other, and, 

 especially in bouillon cultures, 

 groups of filaments, ramified or not, 

 and forming the figure 5 are found. 



Staining reaction — The bacillus stains 

 well with ordinary aniline stains, 

 and holds the Gram. It resists 

 decolorisation by acids even in 

 old cultures, but there is a tendency 

 on the part of the filaments to 

 decolorise. Long subjection to 

 the action of alcohol renders it less 

 resistent to decolorisation by acid. 



Biology : cultural characters — The 

 organism grows well upon all ordi- 

 nary' media. At 37° C. growth 

 appears in from i to 3 days, at 

 ordinary room temperatiu-e in from 

 6 to 10 days. 



Bouillon — On the second day 

 appears a yellow filamentous 

 deposit, with light veil on the sur- 

 fiace but no turbidity of medium. 



