Contamination of Milk. 57 



"cowy" or "animal odor" of fresh milk is an inherent 

 peculiarity that is due to the direct absorption of volatile 

 elements from the animal herself. 



Many kinds of feed consumed by the animal produce 

 a more or less pronounced taint or flavor in the milk. 

 With some plants, such as garlic, leeks, turnips, and cab- 

 bage, the odor is so pronounced as to render the milk 

 quite unfit for use. In some states along the Atlantic 

 seaboard, wild plants of this character in woodland pas- 

 tures may be so abundant as to make it impossible to 

 pasture milch animals. The difficulty in such cases is 

 due to absorption of the volatile principles into the cir- 

 culation of the animal, and if such feed is consumed 

 shortly before milking, the characteristic odors appear 

 in the milk. If consumed immediately after the milk is 

 withdrawn from the animal, sufficient time may elapse 

 so that the peculiar odors are dissipated before the milk 

 is again secreted. The same principle applies in a lesser 

 degree to the use of certain green fodders that are more 

 suitable for feed, such as rape, green rye, or even silage. 

 Silage produces a distinct, but not unpleasant odor in 

 milk, but newly pastured rye often confers so strong an 

 odor as to render the milk unusable. 



Where certain drugs are employed in the treatment 

 of animals, such as belladonna, castor oil, sulfur, or tur- 

 pentine, the peculiar odors may reappear in the milk. 

 Such mineral poisons as arsenic have been known to per- 

 sist for a period of three weeks before elimination. 



On account of the elimination of many drugs, un- 

 changed, from the animal in the milk, the milk of any 

 animal that is receiving medicine should not be used for 

 human food. When such milk is mixed with that of a 

 number of other animals and when it is used by adults, 



