36 THE BUTTER INDUSTRY IN UNITED STATES [260 



hogs. Another objection to this method is that the milk 

 of tubercular cows is mixed with the milk of all the cows 

 in the community, and unless the skim milk is pasteur- 

 ized it is liable to spread bovine tuberculosis if fed to 

 calves and hogs. The transmission of bovine tuberculosis 

 to hogs through feeding butter containing tubercle bacilli 

 or by allowing hogs to have access to' the feces of tuber- 

 cular cows, has been positively demonstrated. 1 The prob- 

 lem of guarding the public health against the spread of the 

 " white plague " therefore not only requires that milk and 

 cream for fresh consumption and milk and cream used to 

 make butter and cheese be pasteurized, but that efforts be 

 made to prevent the spread of the disease among cows and 

 hogs. Some authorities deny that bovine tuberculosis can 

 be transmitted to man : the weight of opinion, however, 

 seems to be on the other side ; and in view of the fact that 

 it may be easily transmitted to hogs, it is by far the wisest 

 plan to take all precautions possible in the protection of the 

 health of the people. Aside from its relation to public 

 health, bovine tuberculosis is an important economic prob- 

 lem. Large numbers of hogs are fed skim milk, and the 

 infection of hogs with tuberculosis means a loss to the 

 farmer. 



The hog may be considered a very important by-product 

 of the butter industry. In Denmark the feeding of skim 

 milk to hogs is considered so important that cooperative 

 efforts have been made to develop the so-called " bacon 

 hog ". This hog is raised for its bacon and lean meat pri- 

 marily, and may be distinguished from the " lard hog " 

 which is fattened so as to yield large quantities of lard. In 

 1887 2 the Danes organized their first cooperative bacon 



1 Circulars 118 and 153, Bureau of Animal Industry, U. S. Depart- 

 ment of Agriculture. 

 a Edwin A. Pratt, Agricultural Organisation, p. 12. 



