256 ANNUAL REPORTS OF DEPARTMENT OF AGRICULTURE. 



FUTURE WORK. 



Besides continuing unfinished work, the following lines of research 

 are contemplated during the coming year and following years: To 

 repeat tests made a few years ago regarding the frequency with which 

 tubercle bacilli occur in butter; to learn if possible whether American 

 oleomargarin (like European, according to European investigators) 

 contains tubercle bacilli in a fairly large percentage of instances; to 

 make additional tests to determine the frequency with which dairy 

 cows eliminate from their bodies the newly discovered bacillus 

 already mentioned; to make additional tests relative to the frequency 

 with which this bacillus occurs in commercial milk; to make addi- 

 tional tests relative to the significance of this bacillus, especially when 

 it occurs in symbiosis with certain other bacilli, and to determine if 

 possible whether the bacillus is associated with some definable con- 

 dition in the bodies of the cows that eliminate it. It is also desirable 

 to make further tests relative to the persistence of tubercle bacilli in 

 a virulent state in manure heaps from stables containing tuberculous 

 cattle. Some work on the subject was done during the past year, 

 but we were not able to carry it out in a way to obtain satisfactory 

 material for rehable conclusions. 



