Contamination of Milk. 35 



the kind in the manure. Unsavory as it may sound, a 

 large part of the bacteria in the milk have their origin 

 in the manure, which, in one way or another, is added 

 to the milk. 



If spoiled or wet feeds such as brewery or distillery 

 slops are fed, intestinal troubles may result with a 

 change in the kind of bacteria found in the manure. 

 Only in this way can the feed influence, in any consid- 

 erable way, the bacterial content of the milk. Moldy 

 and dusty feeds should not be used. The straw used 

 for bedding should be clean. Horse manure should not 

 be used for bedding in the cow stalls. If the feed is 

 such as to render the manure very thin, it is much more 

 difficult to keep the animals clean, thus influencing the 

 number of micro-organisms found in the milk. The in- 

 fluence of impure water is due usually to the fact that 

 the cattle have access to a stream or pond. By wading 

 about in the water their udders are soiled, and at milk- 

 ing some of the water bacteria get into the milk. 



Absorption of odors. Milk absorbs many but not all 

 odors very easily and for this reason it should be kept 

 in a place free from all pronounced odors of any kind. 

 The odors of certain fruits, as bananas, and the odor 

 of strong silage are quickly absorbed by milk. It is a 

 popular belief that milk will not absorb odors when it 

 is warmer than the surrounding air, but experimentally 

 it can be easily demonstrated that the opposite is true, 

 the warm milk absorbing the odors more rapidly than 

 the cold. For this reason milk should always be re- 

 moved from the stable as soon as it is drawn from the 

 animal, for in the stable there is quite certain to be 

 some odor arising frc'n the manure, the animals them- 

 selves, or the feed. The danger of thus tainting the 



