No. 4.] REPORT OF CATTLE BUREAU. 255 



called to the result of Dr. Smith's investigations, he took the 

 matter up and agreed with him in the correctness of his views, 

 and went so far as to say, in a speech at the Congress of 

 Tuberculosis in London, in July, 1901, that there is abso- 

 lutely no danger to the public health from tuberculous cattle. 

 This view was going from one extreme to the other. It 

 seems more reasonable to take a middle course, and assume 

 that, while the danger was over-estimated a few years ago, 

 still there is a slight danger, and delicate persons and young 

 children are sometimes infected with the bovine form of 

 tubercle bacillus through the medium of milk, and that when 

 thus infected the disease may in some instances prove fatal. 



Dr. Smith has found the bovine form of tubercle bacillus 

 in the tonsils and lymphatic glands from persons in several 

 instances, and in some cases fatal results may occur. 



To determine just how great the danger from the use of 

 raw milk from tuberculous cows to human beings may be 

 will require a great many examinations of tuberculous lymph 

 nodes and autopsies; but while the per cent of danger may 

 not be very great, there is positively a certain amount of 

 risk. It is a well-known fact that the milk from cows with 

 tuberculosis of the udder or from those that show marked 

 clinical evidence of disease is very infectious to calves, pigs 

 and small experimental animals, and it is certainly very 

 undesirable to use such milk for feeding children. Milk may 

 become infected in various ways. A cow with a tuberculous 

 udder may excrete the tubercle bacilli directly in the milk, 

 or one with generalized tuberculosis may have a few bacilli 

 pass off through the milk, or the milk may become contam- 

 inated through the dust of the stable or the dirt falling from 

 the cows' flanks into the pail. 



Cows with phthisis do not cough up and expectorate in- 

 fectious material, like the human animal, but swallow what 

 they raise and pass it off through the digestive canal. Recent 

 observations show that the fa?ces of cattle with sufficient 

 lung disease to cough up and swallow infective material are 

 literally teeming with millions of tubercle bacilli. When 

 such a cow lies down, her tail becomes contaminated with 

 the filth of the gutter, and when she swings it she smears 



