JAPANESE CATTLE AND TUBERCULOSIS 147 



(4) This is very important proof for the fact that under ordinary 

 conditions human tuberculosis is not infectious for bovines, as the 

 opportunities for infection certainly cannot be lacking. 



(5) Among Japanese in general very little cow's milk is used 

 and especially is it employed but little for the dietary of children. 



(6) Under natural conditions the native animals show but very 

 little susceptibility for perlsucht. If large doses of perlsucht bacilli 

 are inoculated into them either intravenously or intraperitoneally, 

 they become tuberculous to a certain degree; they do not seem to be 

 at all susceptible to subcutaneous infection. 



1 (7) The imported and mixed race animals are very susceptible 

 to perlsucht. 



(8) Human tuberculosis is not infectious for native and mixed 

 race animals. 



Before concluding I would like to say a few words concerning 

 the two opposing opinions of Koch and von Behring. As is well 

 known, Koch, at the congress in July, 1901, at London, made the 

 statement that human tuberculosis is absolutely different from 

 bovine tuberculosis, a conclusion which he had come to after two 

 years of experimentation on young heifers. Von Behring took 

 issue with this statement at the Congress of Natural Scientists, 

 at Kassel, in September of last year. Von Behring believes that 

 the milk taken by nurslings (cow's milk) is the chief source for the 

 development of tuberculosis. He also stated that human tuber- 

 culosis is identical with that of bovines. 



The fact has already been mentioned that primary intestinal 

 tuberculosis is quite frequent in Japan, even though the natives 

 drink but very little cow's milk, and even though they employ it 

 but very little for the nourishing of their children; if the mother's 

 milk does not suffice, a wet nurse is instantly taken into the house. 

 This clearly proves that human tuberculosis in Japan can only be 

 transmitted from man to man. And from the fact that native 

 Japanese cattle are free from tuberculosis, and also are so little 

 susceptible to it as to make it almost impossible for natural in- 

 fection to take place, we can conclude that bovine tuberculosis 

 was imported into Japan only after the introduction 'of foreign 

 cattle. These importations, however, began only about 30 years 

 ago, while human tuberculosis has existed in Japan as long as we 

 have chronicles. Of especial deciding importance for the statement 

 that human tuberculosis is different from that of bovines is the 

 following: If this were not the case, it would be impossible to find 

 districts in which bovines are entirely free from tuberculosis, in 

 spite of their close connection with tuberculous human beings, and 

 who are constantly giving the domestic animals the opportunity 

 to infect themselves. 



