2 BULLETIN 166, U. S. DEPARTMENT OF AGRICULTURE. 



tion, but especially the reliability of the test. It should be conven- 

 ient, the results should be manifested as early as possible, the reaction 

 should be distinct and well marked, and, probably the most important 

 of all, it should be possible for the practicing veterinarian to apply 

 the test. The last condition must be seriously considered, since the 

 standing of the veterinarian in the community and the confidence of 

 the public, in his work would be more manifest if in suspected cases 

 he could personally decide on the diagnosis instead of havmg to 

 depend entirely on the results of serum tests made at some distant 

 laboratory. 



VARIOUS METHODS FOR DIAGNOSING GLANDERS. 



It would require a great amount of space to enter into the history 

 of the various methods of diagnosis and to enumerate the data we 

 possess on the different tests. The advantages and disadvantages of 

 the various methods, especially of the subcutaneous mallein tests, 

 have been repeatedly published and are accessible to all those who 

 are interested in the subject. There is no question that the sub- 

 cutaneous mallein test is one of the valuable diagnostic agents for 

 glanders, but no one can any longer deny that failures from this test 

 are more numerous than are desirable. As a matter of fact, the 

 uncertainty of the results from this test caused numerous investi- 

 gators to seek some other method which might replace the sub- 

 cutaneous mallein test. Besides the failures resulting from it, the 

 techiiic of executing the test, together with the time required for its 

 determination, make it unpopular with many veterinarians and sani- 

 tary officers . 



Of the other tests which from time to time have been devised for 

 the diagnosis of glanders, the precipitation, the opsonic, and the con- 

 glutination tests will not be considered, since the results obtained 

 from them are not encouraging. 



For laboratory tests the combined agglutination and complement- 

 fixation test will no doubt remain the most satisfactory, and should 

 always be applied in cases where doubt arises as to the results of 

 other tests carried out by the practicing veterinarian. These latter 

 should be considered as accessory tests and provision should be made 

 everywhere so that in case of doubt the serum could be subjected to 

 the laboratory test mentioned, and the final decision should rest on 

 its outcome. 



THE OPHTHALMIC MALLEIN TEST. 



During the last few years the ophthalmic mallein test has gained 

 great favor in the diagnosis of glanders. The popularity of the test 

 is rapidly gaining wherever it has been applied, and among its sup- 

 porters we find at the present time the greatest authorities on the 



