226 DOMESTIC ANIMALS, DAIRYING, ETC. 



meter, while the bacteria in certified milk seldom exceed 30,000 to 

 the cubic centimeter and in most instances average less than 10,000. 

 There have been some cases where commissions have reported that 

 no bacteria were shown to be present by the ordinary methods used 

 for their detection. Liquefying, putrefactive, and pus-forming bac- 

 teria are seldom present in large numbers; in fact the contracts of 

 some commissions with the producers specify that the milk shall not 

 contain pathogenic bacteria or more than a limited number of pus 

 cells to the cubic centimeter. 



Keeping Qualities of Certified Milk. As would naturally be ex- 

 pected, certified milk with its small number of bacteria will keep 

 sweet for a long time. The theory that clean milk should have a 

 long keeping quality works out in practice. Instances are on record 

 where certified milk has been taken on an ocean voyage and not only 

 brought back in good condition but kept sweet until thirty days old. 

 In fact it is now a common practice for people when crossing the 

 water or taking a long land journey with infants to take several 

 cases of certified milk with them. They are then reasonably sure of 

 having a constant supply of sweet milk for several days. Some pro- 

 ducers who guarantee their milk have offices in London as well as 

 in this country so that a supply of fresh milk can be secured by voy- 

 agers going in either direction. This has been a great convenience 

 and has given comfort to many people. Again, a number of certi- 

 fied-milk dairies in the United States sent exhibits of milk to the 

 Paris Exposition in 1900. The milk kept perfectly sweet for two 

 weeks and in some instances 18 days after being bottled and after 

 a summer journey of 3,000 to 4,000 miles. Regular delivery bottles 

 were used, the only extra precaution being to use two paper caps 

 instead of one, and to cover the caps witl^ parafin so as to exclude 

 the air. Of course the milk was carefully packed in ice for shipment, 

 but this was the only means used for preservation. 



Is Certified Milk Worth. -the Extra Cost? In view of the ex- 

 treme care and greater expense required in the production of certi- 

 fied milk, the question is sometimes raised as to whether it is worth 

 the labor and pains necessary to produce it. It must be conceded 

 that pure milk is of vital importance in the feeding of infants. The 

 best way to produce it is by the methods commonly practiced in cer- 

 tified-milk plants' as already outlined in this bulletin. The result of 

 feeding such milk to infants and children in our cities, as shown in 

 the decrease in the death rate, is a matter of common knowledge. 

 Further, with more refined ideas of living, there is a growing de- 

 mand for milk of the highest quality that can be produced. Natur- 

 ally, with the careful methods used in its production, certified milk 

 costs more than ordinary market milk, and the price charged for it 

 is correspondingly higher. In spite of this advanced price, however, 

 a number of certified dairies have failed to make a profit. 



Certified milk, produced under the direction of a reliable milk 

 commission, is worth more than ordinary market milk for several 

 reasons: (1) It is free from disease-producing bacteria, and all 

 other germs are reduced to a minimum. (2) It is free from high 



