Cultivation 



753 



Potato.— The most characteristic growth is upon alkaline potato. 

 It first appears in about forty-eight hours as a transparent, honey- 

 like, yellowish layer, developing only at incubation temperatures, 

 and soon becoming reddish-brown in color. As this brown color of 

 the colony develops, the potato for a considerable distance around it 

 becomes greenish brown. Bacillus pyocyaneus sometimes produces 

 somewhat the same appearance. 



Milk.— In litmus milk the glanders bacillus produces acid. A 

 firm coagulum forms and subsequently separates from the clear 

 reddish whey. 



Metabolic Products. — The organism produces acids and curdling 

 ferments. It forms no indol, no liquefying or proteolytic ferments. 



, Fig. 294. — Culture of glanders upon cooked potato (Loffler). ' 



There is no exotoxin. All the poisonous substances seem to be 

 endotoxins. 



Mallein. — :Babes,* Bonome,t Pearson,t and others have prepared 

 a substance, mallein, horn, cultures of the glanders bacillus', and have 

 employed it for diagnostic purposes. It seems to be useful in veteri- 

 nary medicine, the reaction following its injection into glandered 

 animals being similar to that caused by the injection of tuberculin 

 into tuberculous animals. The preparation of mallein is simple. 

 Cultures of the glanders baciUus are grown for several weeks and 

 killed by heat. The culture is then filtered through porcelain, to 

 remove the dead bacteria, and evaporated to one-tenth of its volume. 

 Before use the mallein is diluted with nine times its volume of 0.5 

 per cent, aqueous carboHc acid solution. The agent is employed 



* "Archiv de Med. exp. et d'Anat. patholog.," 1892, No. 4. 

 t "Deutsche taed. Woch.," 1894, Nos. 36 and 38, pp. 703, 725, and 744. 

 t "Jour, of Comp. Med. and Vet. i^ichiv," Phila., 1891, xn, pp. 411-415. 

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