RULES AND REASONS FOR FARM CARE OF MILK. 



97 



animal are teeming with innumerable microbes. From the time of milk- 

 ing until it is removed from the barn, it is continually exposed to con- 

 ditions that permit of its being infected with bacteria. Even before it 



flows from the udder, it is exposed to con- 

 tamination, for the opening of the teat is 

 always covered with a film of dirt and from 

 this is derived a sufficient quota of bacteria 

 to infect the same. To such an extent is 

 this true, that the first few streams from 

 each teat contain a much larger number 

 of organisms than any subsequent part of 

 the milking. 



In attempting to prolong the keep- 

 ing quality of milk as is done in the 

 milk business, the presence of these organ- 

 isms is a drawback, for the bacteria in the 

 fore milk are in a rapid state of growth, 

 owing to the environment in which they 

 have been kept. Warmth, food and 

 moisture are present in the milk duct to a 

 favorable degree, and a rapid growth can- 

 not but take place. 

 DAIRY UTENSILS. Dirty vessels are a most prolific source of trouble. 

 Old rusty cans that are difficult to cleanse, and therefore are not well cleaned, 



FIG. 1. Sectional view of udder; a, 

 exterior opening of milk duct show- 

 ing opportunity of infection by 

 bacteria from without; b, milk cis- 

 tern; c, milk sinus; d, glandular 

 secreting tissues; e, sphincter mus- 

 cle of teat. The bacteria are unable 

 nnder ordinary conditions to work 

 their way up into milk cistern but 

 the lower portion of milk duct in 

 teat almost invariably contains 

 them. 



FIG. 2. Microscopic appearance of ordinary milk showing fat globules and bacteria in the milk 

 serum. The cluster of bacteria on left side are lactic acid forming germs. 



are a standing menace to the purity of a milk supply. Too much atten- 

 tion cannot be paid to the condition of these milk receptacles. Not only 



