
& 
MILK AFFECTED BY DAIRY PRACTICES. 85 
the most thorough stripping is practiced, to furnish abundant 
food for any bacteria which may remain in the udder after 
milking. It is probable, therefore, that it is not a question of 
food supply which causes this greater increase when a small 
amount of milk is left undrawn. ‘The operation of stripping 
usually brings more bacteria from the udder in each cubic cen- 
timeter of milk than are contained in the milk just preceding 
the strippings. ‘his fact may be shown by figures given in 
Table No. 27. | 
This condition is probably caused by the more vigorous ma- 
nipulation of the udder necessary to draw the strippings, thus 
dislodging from the milk ducts bacteria which have remained 
there during the earlier part of the milking. This means that 
when a cow is thoroughly stripped a smaller number of bacteria 
will be left in the udder. The multiplication of these organ- 
isms during the time intervening before the next milking period 
would not produce as great a number of bacteria-as would 
have been produced had a greater number been left in the 
udder at the preceding milking. It is probable that this is the 
explanation for the fact that there is a greater germ content 
in the milk when the cow has not been stripped dry at the 
preceding milking. While these experiments were conducted 
with but a few cows there is no reason to suppose that the con- 
_ ditions were not normal and that the same conditions would 
not be found to exist in all cows. ‘This adds one more reason 
why cows should be thoroughly stripped. 
INDIVIDUAL MILKERS AFFECT GERM CONTENT OF MILK. 
Every dairyman knows that some milkers will normally keep 
their milk much cleaner than others under the same conditionsas 
to stable, dairy utensils, and other surroundings. Some men nat- 
urally will always have their milk reasonably clean even though 
the conditions are not especially favorable for the production 
of clean milk while other men will naturally always have their 
milk dirty even if the conditions of cleanliness are good. ‘The 
importance of cleanly milkers is becoming more and more im- 
portant in proportion to the public demand for clean milk, and 
it is becoming more and more necessary that dairymen take 
this characteristic into account in hiring men who are to do 
their milking for them. In order to get some definite data in 
