CULTIVATION OF GLANDERS BACILLUS 279 



half a minute ; they are then dehydrated, cleared, and mounted. 

 Gram's method is quite inapplicable, the glanders bacilli rapidly 

 losing the stain in the process. 



Cultivation. (For the methods of separation vide infra.) 

 The glanders bacillus grows readily on most of the ordinary 

 media, but a somewhat high temperature is necessary, growth 

 taking place most rapidly at 35 to 37 C. Though a certain 

 amount of growth occurs down to 21 C., a temperature above 

 25 C. is always desirable. 



On agar and glycerin agar in stroke cultures growth appears 

 along the line as a uniform streak of greyish-white colour and 

 somewhat transparent appearance, with moist-looking surface, 

 and when touched with a needle is found to be of rather slimy 

 consistence. Later it spreads laterally for some distance, and 

 the layer becomes of slightly brownish tint. On serum the 

 growth is somewhat similar but more transparent, the separate 

 colonies being in the form of round and almost clear drops. In 

 sub-cultures on these media at the body temperature growth is 

 visible within twenty-four hours, but when fresh cultures are 

 made from the tissues it may not be visible till the second day. 

 Serum or potato, however, is much more suitable for cultivating 

 from the tissues than the agar media ; on the latter it is some- 

 times difficult to obtain growth. 



In broth, growth forms at first a uniform turbidity, but soon 

 settles to the bottom, and after a few days forms a pretty thick 

 fiocculent deposit of slimy and somewhat tenacious consistence. 



On potato at 30 to 37 C. the glanders bacillus flourishes well 

 and produces a characteristic appearance ; incubation at a high 

 temperature, however, being necessary. Growth proceeds rapidly, 

 and on the third day has usually formed a transparent layer of 

 slightly yellowish tint, like clear honey in appearance. On sub- 

 sequent days, the growth still extends and becomes darker in colour 

 and more opaque, till about the eighth day it has a reddish-brown 

 or chocolate tint, while the potato at the margin of the growth 

 often shows a greenish-yellow staining. The characters of the 

 growth on potato along with the microscopical appearances are 

 quite sufficient to distinguish the glanders bacillus from every 

 other known organism (sometimes the cholera organism and the 

 b. pyocyaneus produce a somewhat similar appearance, but they 

 can be readily distinguished by their other characters). Potato 

 is also a suitable medium for starting cultures from the tissues ; 

 in this case minute transparent colonies become visible on the 

 third day and afterwards present the appearances just described. 



Powers of Resistance. The glanders bacillus is not killed at 



