84 PRINCIPLES AND PRACTICE OF MILK HYGIENE 
losis commission found the feces infectious from tuber- 
culous cows which did not show any clinical symptoms, 
but these results have not been confirmed by others. 
Titze, Thieringer and Jahn*® demonstrated tubercle 
bacilli in the feces of cows affected with open pulmonary 
tuberculosis, but not in the feces of reacting cows which 
did not show clinical symptoms. Traum ** inoculated 
guinea pigs with fecal material from 36 cows, “ prac- 
tically all tuberculin reactors,” and none of the guinea 
pigs was infected with tuberculosis, although two of the 
cows exhibited physical symptoms of disease of the lungs. 
These results correspond with those obtained when 
samples of mixed milk from herds known to be infected 
with tuberculosis have been examined for tubercle bacilli. 
For example, O. Miiller examined samples of milk from 
1598 herds in East Prussia and tubercle bacilli were 
demonstrated in the samples from only 97 herds, al- 
though non-clinical reactors were present in the other 
herds. In the 97 herds from which the samples contain- 
ing tubercle bacilli were obtained, cows were found which 
exhibited clinical symptoms of udder tuberculosis or 
other forms of the disease. Similar results could be 
cited. Reichel *” found the feces infectious from cows 
which were not tuberculous but which were stabled with 
cows affected with open tuberculosis. It therefore ap- 
pears probable that the sputum coughed out by cows 
with open tuberculosis, or the fine spray expelled from 
the mouth in coughing, may contaminate the feed of other 
15 Arbeit. K. Gesundheitsamt, pp. 1-34, No. 1, 1913. 
16 Annual Report University of California Expt. Station, 
1915, p. 40. 
17 Verbal communication. 
