STANDARD MILK 81 



In order to protect themselves and their customers, the milk 

 peddlers, the Boston contractors have established their own chem- 

 ical laboratories, in which every producer's milk is periodically- 

 analyzed. If any lot falls below the standard, the producer is 

 not prosecuted ; but instead is warned, and if no improvement 

 results, the contractor will no longer buy his milk. That this 

 is necessary has been verified over and over again by the results 

 of analyses made in this laboratory. Sample after sample of. 

 milk has been found to be fai' below the average composition in 

 the percentages of total solids and fat. 



Without any adulteration some milk may fall below the 

 standard because there must be some milk below the average 

 composition, and some above it. When a farmer has a herd of 

 cows in which the individuals producing poor milk outweigh 

 those yielding good milk, his average product must fail below 

 the standard. To produce standard milk the farmer must select 

 cows whose individual products will blend to make an average 

 quality of milk. 



It is always unlikely that any two cows in one herd will give 

 milk that is exactly alike in composition. No experiment sta- 

 tion has yet succeeded in feeding cows in such manner that the 

 quality of the milk has been changed in a marked degree. All 

 authorities agree that the composition of milk is dependent on 

 the animal, and like color, form, and size, is modified by breed- 

 ing. It is well known that our leading breeds of cattle vary in 

 the quality of their milk, when the averages of the breeds are 

 compared. 



The Holstein breed is especially apt to fall below the standard. 

 In the report of the Holsteiu-Friesian Association for 1902, 

 there are given the results of 733 individual tests, none of which 

 was for less than seven days ; and but 126 would pass our winter 

 standard, while 114 would fail to reach the summer standard. 

 These results were obtained, as a rule, from cows in the early 

 stages of lactation. 



The results of our tests of herds in this state, for the Ayrshire 

 Breeders' Association, show that the average fat was 3.88 per 

 cent, and the total solids 12.55 per cent.^ 



The published averages for other breeds are as follows :2 



^Bulletin 96, p. 118. 



^Nahrungs und Genussmittel. Koenig. 1, p. 297. 



