THIRTEENTH ANNUAL YEAR BOOK— PART XI 



569 



No. 3. — 'The cow shown in this picture is apparently healthy. She does not 

 cough, her appetite is good and her general condition is excellent 

 for a milk cow that has recently calved. At the time her picture 

 was taken it was known that she had been affected with tuberculosis 

 at least 4^^ years and that she had been passing tuberculosis germs 

 from her body for a long time. The calf by her side is the fourth 

 she has produced in the last four years. Small quantities of her dung 

 caused tuberculosis in guinea pigs when it was placed under their 

 skin. 

 The mixed dung of this cow and of the one shown in the last picture 

 caused tuberculosis in hogs that were permitted to eat it. 



