DIAGNOSTIC INOCULATION. ?3/ 



malleiri are due to differences in the character of the mallein 

 used. 



Serum Diagnosis by Means of Agglutination. 



The term Agglutinate is used to designate the character- 

 istic of Blood Serum, which enables it to precipitate living 

 as well as dead bacteria in the form of clumps. The active 

 elements in this process are called Agglutinines. The normal 

 blood serum of the horse agglutinates glanders bacilli in a lim- 

 ited degree. However, if a horse is affected with glanders, 

 the agglutinines appear in larger masses. 



In order to make an Agglutination Test for glanders, the 

 serum of the blood of the suspected horse is prepared in 

 various dilutions by means of the addition of a physiological 

 salt solution. In order to determine the agglutinating power, 

 equal quantities of emulsions of glanders bacilli which have 

 been destroyed by heating at 60°C. (test fluid) are added to 

 the serum solutions. 



Horses, the blood serum of which will agglutinate gland- 

 ers bacilli in dilutions of 1 :1000 or in greater dilutions, must 

 be regarded as affected with glanders. Agglutinating powers 

 ranging from 1 :500 to 1000 are doubtful. Agglutinating pow- 

 ers in dilutions of 1 :400 to 500 indicate the absence of gland- 

 ers. Exceptions occur in all of these cases. In case of doubt- 

 ful results, the test must be repeated after the lapse of a 

 certain period of time. 



The real weakness of the agglutination test consists on the 

 one hand in the fact that horses that have chronic glanders 

 frequently have a very low agglutinating power and, on the 

 other hand, healthy horses sometimes possess an agglutinating 

 power as high as that usually found in glandered horses. 



Since it is the degree of agglutination and not agglutina- 

 tion itself that determines whether or not infection is present, 

 the misinterpretations of results are unavoidable. Of course 

 we can use for comparison such results only as have been 

 produced by the same test fluid. 



