Contamination of Milk. 31 



the remainder of the milk. Even when the milking is 

 most thoroughly done, there remains in the milk ducts 

 of the udder, a few drops of milk that afford sufficient 

 nutriment for the development of any germs that may 

 gain access through the opening of the teat. Accord- 

 ing to Gernhardt, it is possible that they may penetrate 

 the udder as far as the milk cisterns or gland tissue itself, 

 but the evidence on this point is not decisive. The rela- 

 tively high temperature of the teat facilitates a rapid 

 growth. 



Under these conditions, a small number of organisms 

 are able to increase in such numbers that the first few 

 spurts of milk contain many more than those which are 

 subsequently drawn. The following data by Harrison 1 

 strikingly illustrates this point: 



Number of bacteria per cc. in milk. 



Foremilk 26,070, 25,630, 38,420, 18,110, 54,800, 32,700, 



43,520, 27,830, 18,500, 29,400, 45,630, 48,700. 

 Milk after removal 



of fore milk 1,246, 1,150, 1,430, 3,420, 1,560, 890, 



2,575, 4,820, 3,270, 1,285, 1,350. 



If the fore milk is received in a separate vessel and 

 kept protected from the air, it will generally be noted 

 that it sours more rapidly than the remainder of the 

 milk. 



As a rule the number of different species found in the 

 fore milk is usually small, not more than one or two 

 forms being present at any time. As to the character 

 of these forms data is conflicting. Harrison 2 reports 

 finding peptonizing bacteria in the same, and Marshall 3 

 states that organisms are found that resist pasteurizing, 



1 Harrison, 226! Kept. Ont. Agr'l. Coll., p. 108, 1896. 



M. c., p. 108. 



8 Marshall, Mich. Expt. Stat., Bull. 147, p. 42. 



