1 88 AGRICULTURE OF MAINE. 



Aside from the danger from tuberculosis, the greatest dan- 

 ger of milk causing disease in the human subject lies in the bac- 

 teria that enter it after it comes from the cow's udder. Aside 

 from tuberculosis and garget, there is no danger from inside 

 the udder ; no physical dirt comes from inside the udder. After 

 the milk has left the cow, bacterial dirt can enter it either at- 

 tached to the physical dirt from the cow, her surroundings, or 

 the different milk utensils and the places where they are kept; 

 or from the person of those who handle the milk, whether in 

 milking, preparing the milk for the market, or in the marketing. 

 Some of these cause disease in the users of the milk; some 

 cause rapid souring of the milk, but no disease in the human 

 subject; and some cause odors, tastes, colors and changes in the 

 physical appearance of the milk, as in the case of ropy milk, 

 without causing disease among the users of it, although, in these 

 latter cases, the physical condition of the milk unfits it for use, 

 and would cause its rejection by farmer and consumer alike. 

 The dangerous, disease causing germs give no hint, however, of 

 their appearance until the person is taken sick. 



The most common forms of bacteria that gain access to a 

 milk are the lactic acid group, which cause souring. These are 

 present everywhere about farms and dairies, and, as they are 

 everywhere in the air attached to dust particles, it is impossible 

 to entirely keep them out of the milk; although proper precau- 

 tions in cleaning the cow, keeping the stable and milk rooms 

 scrupulously clean, and protecting the milk pails from the en- 

 trance of dust by proper strainers, will practically eliminate 

 them ; and will make it possible to thoroughly control the growth 

 of the few that do enter the milk. These bacteria do not cause 

 disease among the users of the milk. They are harmless to 

 the human family, but a source of very great economic loss to 

 the producer through the lessened keeping power of his prod- 

 uct. In addition to the lactic acid group there are very many 

 other bacteria that cause souring of milk ; many of which are 

 of intestinal origin, and produce harmful results in the human 

 subject. These being derived from the intestines of the cow 

 both can be, and should be, excluded from the milk. 



The various bacteria that change the physical condition of the 

 milk through making it ropy, or giving it color, odor or taste, 

 also enter it in the dirt and dust about the stables and milk 



