42 Dairy Bacteriology. 



brush, it can be kept in a sanitary condition. But when- 

 ever any portion cannot be thus reached, whether it is 

 an angle or a seam in a pail or can, the interior of the 

 separator bowl, or in the pipes used for conducting milk, 

 contamination is certain to result from such places, un- 

 less extreme care is taken to destroy the bacteria therein 

 by steaming. 



Contamination from the animal. In the process of 

 milking, the bacterial content of the milk is materially 

 increased. In part this comes from the utensils into 

 which the milk is drawn, but the animal herself, the 

 milker, as well as the surrounding air, also contribute to 

 a varying extent. Of these factors, the one fraught by 

 far with the most consequence, is the influence of the 

 animal herself. It is a popular belief that the organisms 

 found in milk are derived from the feed and water which 

 the animal consumes, but under normal conditions, the 

 bacteria consumed in food pass through the intestinal 

 canal and do not appear in the circulation. It must not 

 be assumed, however, that the character of feed and 

 water supply is of no moment. Stock should be given 

 pure and wholesome water and no decomposed or spoiled 

 food should be used. 



The infection traceable directly to the cow is modified 

 materially by the conditions under which the animal 

 is kept and the character of the feed consumed. The na- 

 ture of the fecal matter is in part dependent upon the 

 character of the food. The more nitrogenous the ration 

 fed, the softer are the fecal discharges, producing a 

 condition which is more likely to soil the coat of the an- 

 imal unless care is taken. The same is true with ani- 

 mals kept on pasture in comparison with those fed dry 

 fodder. 



