N'o. 7. DEPARTMENT OF AGRICULTURE. 85 



tute for tjie Study, Treatment and Prevention of Tuberculosis, to 

 malve an investigation of the worlv that had been done and that was 

 in progress in Europe in relation to the artificial immunization of 

 cattle against tuberculosis. As the subject of this inquiry was in the 

 exact line of work that has been conducted for a long time and on 

 a large scale by the State Livestock Sanitary Board, it was con- 

 sidered to be advisable that I should accept the invitation. Accord- 

 ingly, I was given a short leave of absence by the State Livestock 

 Sanitary Board and devoted two months to the investigations re- 

 ferred to. A report has been written upon the results of this investi- 

 gation and it will soon be published. As to the general results, it 

 may be said that, while considerable work is now in progress in 

 Europe in relation to the artificial immunization of cattle against 

 tuberculosis, no experiment is now being conducted that will fur- 

 nish the precise information that is needed to accurately measure 

 and determine the effects or different methods of vaccination or that 

 may yield the information that is needed to put vaccination of cattle 

 upon a practicable working basis. I may here record the fact that 

 our work of investigation in this field has been looked into by a 

 commissioner of the German Government who stated that, in his 

 opinion, no other investigation in this field is so well planned to fur- 

 nish the information required in order to determine the exact value 

 and efficiency of different methods of vaccination against tubercu- 

 losis, and to furnish the information needed in order to make the 

 process of direct advantage to farmers. 



During the year, it has been necessary to condemn, as tubercular, 

 1.487 cattle in 781 herds. 



The following paper, read before the Pathological Society of Phila- 

 delphia, December 22, 1904, gives the results of some of our observa- 

 tions on the healing of tuberculous lesions by vaccination: 



THE EFFECT OF TUBERCULOSIS VACCINATION UPON CAT- 

 TLE INFECTED WITH TUBERCULOSIS. 



By Leonard Pearson, B.S., V.M.D., 

 State Veterinarian of Pennsylvatiia, 



AND 



S. H. GiLLlivAND, V.M.D.,. M.D., 



Bacteriologist oj the State Livestock Sanitary Board of 



Pennsylvania. 



During recent years a large amount of work lins been done by 

 Koch, Trudeau, de Schweintz, von Behring, Maragliano, Fraenkel, 

 and others, for the purpose of discovering and developing a specific 

 treatment for tuberculosis. This work has taken various directions, 

 and has included experiments wherein the toxins of tubercle bacilli 

 have been administered and experiments where antitoxins found 



