128 PRINCIPLES OF VETERINARY SURGERY 



Cultivation. — It can be grown in bouillon, milk, and 

 upon the usual solid media. It grows particularly well 

 upon glycerin agar-agar and upon blood serum. It grows 

 best between 75*" and no" Fahr. 



Isolation. — The most satisfactory and effectual method 

 of obtaining the bacillus unassociated^ is by inoculating a 

 cavy with pus from a gland or nodvile and then securing- the 

 bacillus from its tissues. Attempt to isolate it by the usual 

 smear-culture method generally fails owing to the presence 

 of the associated bacteria which usually grow more rapidly 

 than the specific microbe. When animals are inoculated 

 for this purpose the appearance of secondary lesions is 

 awaited and then the culture is obtained from the soft pus- 

 tule before it ruptures and has thus been exposed to ex- 

 ternal micro-organisms. 



Staining. — The Jpacillus mallei will not take Gram's, but 

 can be stained with the aqueous solutions of the anilin dyes. 



Virvilence and Resistance. — The ciiltivation through sev- 

 eral successive generations reduces the virulence markedly. 

 Attenuation by the use of heat has not been successful, the 

 micro-organism being promptly killed by an exposure of 

 five minutes to a heat of 130° Fahr. It yields to the ordi- 

 nary disinfectants, but is capable of resisting desiccation 

 for several months and, very probably, much longer. The 

 marked resistance of the bacillus mallei to desiccation would 

 indicate that it is a sporogenous microbe, which is however 

 not the case. It is simply very resistant to the various ex- 

 traneous influences to which it might be subjected in the 

 stable and out-of-door environments. 



Pathogenicity. — When injected into the tissues of re- 

 ceptive animals, the bacillus mallei will cause the well- 

 known disease glanders, the lesions of which will always 

 be found to contain the bacillus. It is capable of producing 

 both an acute and a chronic glanders and of localizing in a 



