DAIRY, SEED IMPROVEMENT, STOCK BREEDERS' MEETINGS. I93 



they have been planted and the character of the growth deter- 

 mined, but the presence of such seeds as corn or beans could be 

 easily detected by observation. 



For the detection of tubercle bacilli in milk, six weeks is 

 necessary. Typhoid and diphtheria bacilli can be detected in 

 four or five days and for the determination of the relative 

 virulence of streptococci two or three days is necessary. The 

 enormous expense of carrying on routine work of this nature 

 makes it prohibitive, and for this reason regulations relating to 

 bacteria in milk refer to total numbers rather than to the quan- 

 tity of the specific bacteria which may cause sickness to the 

 people using the milk. 



Bacteria are present in milk as a suspension and this sus- 

 pension is not always uniform. For this reason analyses 

 should be made from several samples and the results reported 

 as averages of all determinations. Final conclusions should be 

 drawn only after a series of examinations. Comparisons are 

 of moment only when the numbers are greatly divergent, thus 

 the difference between 50,000 and 55,000 bacteria may be due 

 to differences in sampling or in methods of estimations, but 

 differences between 50,000 and 500,000 bacteria show conclu- 

 sively that the articles were produced and kept under vastly 

 different conditions. 



New York City has established a milk grading system which 

 seems to put a premium on milk of low bacteria content. The 

 merits of this system can be enjoyed by the farmer as well as 

 the consumer. This system, which can be easily controlled when 

 dealing with a congested population, prohibits the sale of raw 

 milk unless of a quality resembling certified milk. Under this 

 regulation the producer of this grade milk most certainly must 

 be well paid for the product. This milk must be obtained from 

 tuberculin tested cattle which are housed in stables of a mini- 

 mum score on the special score card of the New York City 

 Health Department, and the bacteria content must be below a 

 certain fixed maximum when delivered to the consumer. All 

 other milk must be pasteurized, and, if the bacteria content of 

 the raw milk is above a certain fixed maximum, the milk cannot 

 be pasteurized and sold unless labeled "Grade C, for Cooking 

 Purposes Only." In order to avoid the alternative of marking 



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