92 MODERN DAIRY PRACTICE. 



Kinds, not Numbers, of Bacteria of Most Importance. 

 It must be remembered, however, that in the infection 

 of milk with bacteria, as in every other infection, the main 

 importance does not lie in the large or small number of 

 bacteria, but in their qualities and nature. It is a com- 

 mon observation that a large number of different kinds of 

 bacteria are found in the milk by the first examination in 

 the stable, but in later examinations of the same milk 

 the number of different kinds will be found considerably 

 reduced. The struggle for existence thus seems to be as 

 pronounced in the microscopic as in the macroscopic 

 world. The milk is infected from different sources by 

 different kinds of bacteria, and each of them begins to 

 hunt for sustenance in the new nutritive medium, and 

 seeks to gain superiority over the others. The struggle is 

 for life and for the greatest power, for even among these 

 pygmies of the living world the old maxim holds good, 

 that he who has the power appropriates for himself all the 

 good things of life. The organisms, for one reason or 

 another gaining the upper hand, increase so rapidly that the 

 others at best can only just save their lives, and are unable 

 to exert their vital functions on a large scale. They remain 

 helplessly in the minority as long as the conditions are favor- 

 able for their more favored conquerors. We thus find that 

 only a few forms of bacteria have been able to increase in 

 preponderating numbers in samples of milk that have been 



from 35,000 to 275,000 was found per cc. on an average during April 

 (1894), and from 380,000 to 2,000,000 per cc. during May and June 

 See also foot-note on p. 87. 



Pammel (Iowa Experiment Station Bulletin No. 21, p. 801) found 

 571,900 bacteria in milk " just before the curd was ready to cut for 

 cheese" ; another sample contained 165,000 bacteria per cc. W. 



