No. 6. bEPArwTMENT OF AC I tK'lJLTUiiE. 101 



it lias been found that tlio qntirantiue can be raised after the fouii ii 

 or lif(h tci-t. This system lias been in operation for several years 

 and horses that have at one time been under suspicion and have 

 be( n frei'd from suspicion in (he maniu'r stated, have been under 

 observation since for two, Ihree or four years and have shown 

 no evidence of glanders and have not propagated glanders among 

 the horsrs v\itli which llicy have worked and have been stabled. 

 TJnforluiialely, it has not often berii possible to make post mortem 

 examiualioiis on horses so treated, but through so much of this 

 wori< as it has been jjossible to do here, and through work of this 

 character (hat has been done abroad, th(n'e appears to be little 

 ground to doubt that under such conditions the disease may be 

 actually cured and that such nodules as are found in the lungs 

 or elsew^here, may be free from living bacilli of glanders. In a 

 number of cases it has been found that horses that do not cease 

 reacting to the mallein test, subsequently break down with this dis- 

 ease. Since, however, such horses are continued in quarantine no 

 harm has come from permitting them to remain alive until the 

 disease has reached a stage of development rendering it possible 

 to diagnose it by means of a physical examination. If such horses 

 had not been tested with mallein, since they did not at first show 

 external signs of glanders, they could not have been kept under 

 careful observation and under the complete or partial quarantine 

 that they were kept under, and so they would have had an oppor- 

 tunity to have distributed infection. 



This method of dealing with glanders has the advantage of being- 

 conservative to a very high degree and at the same time of being- 

 effective. In other words, by means of it, it is possible to eradicate 

 glanders with .a minimum of expense and loss. No horse is de- 

 stroyed that does not present physical signs of glanders, and no 

 horse that has once reacted is relieved of suspicion until he has been 

 under observation for at least three months, during which time he 

 has shown no evidence of glanders either upon physical examination 

 or repeated mallein test. 



The efticiency of this method is perhaps best shown by the infre- 

 quency of glanders in Pennsylvania, and the fact that the cases that 

 do occur, can, in practically all instances, be traced to infection from 

 without the State. 



Whether mallein may actually be classed as a curative agent or 

 not is a point u])on which evidenc'e gathered in this work is insuffi- 

 cient to base [in opinion. It may be, as is held by some, that glan- 

 ders is a disease from which in its very earliest stages a large pro- 

 portion of horses recover, and that the disappearance of the mallein 

 reaction in horses that have been exposed and have once reacted, 

 is but evidence of the course that the disease naturallv follows in 



