I30 Bulletin 65. 



man view that it is impolitic to destroy those that are only slightly 

 aflfected. If tubercle exists, to however limited an extent, tuber- 

 culin tends to aggravate it, and the owner who wishes to preserve 

 his mild cases cannot desire to have them made worse, which 

 means to have the disease extended and possibly generalized. 



So in government sanitary work. Unless the government is 

 prepared to slaughter and pay for every animal aflfected with 

 tuberculosis in however slight a degree, it has no right to use a 

 tuberculin test. It is only when the State means to make thor- 

 ough work in eradicating tuberculosis from the herds that the 

 tuberculin test is at all admissible. But when the State aims at 

 the thorough extinction of the disease in our herds this test can- 

 not be omitted, as it is absolutely essential to success. The tem- 

 porary aggravation of the disease is no possible harm, when the 

 animal is to be promptly killed and paid for. 



To sum up : The tuberculin test aggravates existing tuber- 

 culosis and is, therefore, unwarrantable for use on man or on cat- 

 tle that are to be kept alive ; it is, however, the only known 

 means of detecting many occult cases of tuberculosis and is, 

 therefore, indispensible in any systematic eflfort to stamp out the 

 disease by the purchase and slaughter of every tuberculous 

 animal. 



Meat and Milk of Tuberculosis Animals Unfit for Food. 



In this connection we must consider two questions essentially 

 distinct from each other and equally important in a sanitary sense. 

 The first is the question of infection by the use of such food prod- 

 ucts, and has been very fully investigated by pathologists and 

 sanitarians. The second question — is that of poisoning by the 

 pernicious products of the germ and has hitherto been entirely 

 ignored by sanitary writers and administrators. It will be con- 

 venient to consider these questions separately. 



I. Infection by Bacilli in Meat and Milk. 



First however it will be instructive to compare the geographic 

 distribution of cattle and that of tuberculosis, not with the view 

 of showing that most of the tuberculous infection of man comes 

 from cattle, for it probably comes maialy from his fellowman, but 

 to demonstrate rather that in some way the intimate relation of 

 cattle to man is a potent agent in the extension and maintenance 

 of consumption in the human famil}'. To the student of this 



