AVIAN TUBERCULOSIS. — EXPERIMENTAL STUDY. 535 



This case, which we reported to the Societe de Biologic, appeared 

 to us interesting for several reasons. It furnished a new example of 

 varying resistance in two animals of the same species inoculated in the 

 same way. It furnished a good type of experimental tuberculous joint- 

 disease. Finally, it showed that animals affected with avian tuberculosis 

 reacted to tuberculin like animals affected with human tuberculosis ; in 

 both cases large doses of tuberculin produce death with intense con- 

 gestive symptoms precisely similar to those just described. 



To sum up, avian tubercular material, when inoculated into the peri- 

 toneum of the rabbit, generally produces tuberculous granulations ; in 

 most cases all the viscera are affected, and death occurs on an average 

 at the end of eighty days. In some cases, however, the animals remain 

 to all appearance in good health, and when killed astonish the experi- 

 menter by displaying generalised tuberculosis. 



It will be seen how greatly our results differ from those of Rivolta 

 and Maffucci. These two Italian investigators regard avian tuberculosis 

 as scarcely pathogenic for the rabbit, and as only producing a few very 

 discrete pulmonary granulations. From our experiments it will be seen 

 that the virus, when introduced into the peritoneum, produces general- 

 ised tuberculosis, and, in fact, acts on the rabbit as does mammalian 

 tuberculosis. 



Inoculation of Guinea-pigs. — The experiments of Rivolta and Maffucci 

 have shown, as we said, the great difficulty of transmitting avian tuber- 

 culosis to guinea-pigs. MM. Cornil and Megnin, who inoculated two 

 guinea-pigs, failed to discover any visceral changes when the animals 

 were killed two months later ; the subjects only showed an abscess 

 containing bacilli in the abdominal wall. They thought that generalisa- 

 tion would have occurred had they waited longer before terminating 

 the experiment. 



MM. Straus and Gamaleia, after intra-peritoneally inoculating 

 guinea-pigs with avian tuberculosis, found that death occurred in two 

 to four weeks. On post-mortem examination no lesion was found, or 

 the spleen simply appeared rather large and red ; in whatever way the 

 material was introduced, tubercles failed to develop. These observers 

 several times detected bacilli in the viscera, but the organisms had 

 never produced any formation of nodules. 



Our experiments extended to twenty-four guinea-pigs, which were 

 intra-peritoneally injected with emulsions prepared with material from 

 the livers of tuberculous birds. In several cases we simultaneously 

 injected a few drops under the skin. 



