264 GENERAL THERAPEUTICS FOR VETERINARIANS 



or in the evening. When the mallein is instilled in the morning, the reaction 

 will appear at the earliest in the afternoon; when it is made in the evening, 

 the first observation of the eye can be made the next morning. 



Since drops of pus flowing from the eye and sticking to the hair may be 

 thrown off by movements of the head and thus escape detection, restless horses 

 should be tied up short during the test. 



The presence of fever does not interfere with the application of the test. 



The test does not influence the blood test. 



III. Judgment. — The test may terminate in three ways: positive, nega- 

 tive, doubtful. 



The reaction is positive if a purulent discharge from the eye occurs in 

 12 to 24 hours. 



The reaction is negative if a discharge from the eye does not appear in 

 12 to 24 hours. 



The reaction is doubtful if after 12 to 24 hours only a serous, Beromucous 

 or mucous discharge occurs from the eye, or if only a drop of purulent secretion 

 collects in the inner canthus of the eye without any discharge. 



The judgment of the test is based upon the following principles: 



1. The presence of glanders is assumed as probable if a positive reaction 

 occurs 12 to 24 hours after the instillation of the mallein. 



2. The absence of glanders is assvuned as probable if a negative reaction 

 occurs 12 to 24 hoiu-s after the instillation of the mallein and if, in addition, 

 a negative reaction is again obtained upon a repetition of the test three weeks 

 later. (In the initial stages of glanders the hypersensitiveness to mallein is 

 absent; this appears only toward the second week after infection.) 



3. If the reaction to the first test is doubtful, a second test is begun on 

 the same day. If the reaction to the second test is positive, the presence of 

 glanders is assumed as probable. If the reaction to the second test is negative 

 or doubtful, then a third test is made after 3 weeks. If the reaction to the 

 third test is negative, it is assumed as probable that glanders is not present. 

 If the reaction to the third test is positive, the presence of glanders is assumed 

 as probable. If the reaction to the third test is doubtful, the horse remains 

 under suspicion of glanders. 



