298 MANUAL OF BACTERIOLOGY. 



This bacillus is pathogenic 1 to guinea-pigs, field-mice and 

 cats; rabbits, sheep and dogs are less susceptible or only 

 slightly so, also white and house-mice, and hogs ; cattle are 

 immune. Men are occasionally affected, especially those 

 who have come in contact with horses. The mucous mem- 

 brane of the nasal cavity may be the part involved, or the 

 skin, or the internal viscera. In a number of instances, 

 workers in the laboratory have been accidentally infected. 



The diagnosis of the disease is best effected by the in- 

 oculation of a male guinea-pig with the material from a 

 case suspected of being glanders, introducing it into the 

 peritoneal cavity (Method of Straus). In about two to 

 three days there appears a characteristic swelling of the 

 testicle indicating the beginning of suppuration, which 

 presently takes place ; the animal usually dies after two or 

 more weeks. At least two guinea-pigs should be inocu- 

 lated: and the test may sometimes fail, when it should be 

 repeated on other guinea-pigs. 2 



Mallcin is a product obtained from an old glycerin- 

 bouillon culture of the bacillus mallei. The cultures are 

 placed in a steam sterilizer for several hours, and are fil- 

 tered through unglazed porcelain. The filtrate contains 

 the products of the growth of the bacillus mallei and is of 

 much the same character as tuberculin. Injected into ani- 

 mals suspected of having glanders, if it produces a local 

 and febrile reaction, the existence of glanders is indicated. 

 It is usually successful in the diagnosis of the disease in 

 lower animals, especially in horses, where it has been 

 largely employed. An agglutination reaction has been de- 

 scribed for the bacillus of glanders. 



1 The statements of different writers differ considerably \\ilh regard 

 to some of these animals. 

 2 Frothingham, Journal Medical Research. Vol. VI., 1901. 



