628 INFECTION AND IMMUNITY. 



1 to 500 dilution is a valuable aid to diagnosis. 

 Normal horse serum is said to agglutinate glan- 

 ders bacilli at times in 1 to 250 dilution. Agglu- 

 tination in dilution of 1 to 5,000 and 1 to 10,000 

 has been observed. By active immunization of 

 animals an agglutinating serum may be obtained, 

 and such a serum may be used for the diagnosis 

 of glanders bacilli. Precipitins are also formed. 

 Treatment of glanders with immune serums has 

 use of not been successful. Such treatment has been at- 



Mallein. , , _ . , . n . . , . 



tempted with serum prepared by immunization 

 with mallein (Semmer), and with the serum of 

 diseased animals (Hell and Toeper). The value 

 of mallein in the diagnosis of glanders or farcy is 

 similar to that of tuberculin in tuberculosis. Al- 

 though it causes a rise in the temperature of nor- 

 mal animals when given in considerable doses, the 

 reaction produced in infected animals is so much 

 more intense, and occurs with such smaller doses, 

 that it is generally considered as specific in nature. 

 Some doubt, however, has been thrown on the spe- 

 cificity of the reaction from the facts reported by 

 various observers that toxic substances from other 

 organisms, as tuberculin and preparations from 

 the pneumobacillus of Friedlander, Bacillus 

 pyocyaneus, etc., cause similar phenomena in ani- 

 mals suffering from glanders. Wladimiroff asserts, 

 however, that the reactions caused by these sub- 

 stances differ from that of maliein. 



For diagnosis a dose must be used which causes 

 no reaction in a normal animal, and this varies 

 with different preparations. The typical reaction 

 has two essential components: 1, A rise in tem- 

 perature which begins in from six to twelve hours 



