18 BACTERIA 
that 25 per cent are infected by the tuberculosis 
bacteria of cows. This means that cows carry 
these germs to children. Tuberculosis is com- 
mon in cows. When the disease reaches the 
udder, the bacteria are discharged into the milk. 
A tuberculous cow also discharges large num- 
bers of these bacteria from her bowels. Manure 
from tuberculous cows is dangerous and its dust 
spreads the disease. 
4. Diphtheria. The bacteria of diphtheria grow 
well in milk. Diphtheria in the throats of the 
hired help on the dairy farm may get into milk 
through coughing or sneezing or from the milker’s 
fingers. Many epidemics of diphtheria among 
milk drinkers have been caused in this way. 
When dairy cows are diseased or when there is 
disease in the farmer’s family or among the hired 
help, the whole business of a dairy farmer may 
be destroyed by the health authorities. Every 
dairyman must protect his business by quickly 
reporting disease when it occurs, so that the 
authorities can help him protect milk consumers 
and also save his business. 
