The Herd and the Dairy 261 



states requires that such milk be pasteurized (heated) Pasleuriza- 

 before it is sold. Such milk if pasteurized is harmless, ^lik 

 for the heat kills any dangerous germs that may be in it. 



There is a way of finding out whether or not a cow The tuber- 

 has tuberculosis. A liquid known as " tuberculin " is 

 injected into the blood of the cow, and if it causes her 

 to have fever for a few hours she has the disease. If 

 she is free from the disease, no fever is caused by the 

 injection. 



In many places milk is graded and priced according Grades of 

 to quality. The highest grade is known as " certified 

 milk." It often sells for nearly twice as much as milk 

 of a lower grade. Other milk may be classed as " Grade 

 A," " Grade B," etc. In order to have milk certified, 

 some one representing the health board must visit the 

 dairy frequently and certify to the board of health that 

 the milk is produced in accordance with their require- 

 ments. 



These requirements are generally like the following : Require- 

 (i) The cows must be tuberculin tested and found free j or 

 from disease. (2) The milkers must be free from any 

 contagious disease and stay away from any house where 

 there is contagious disease. (3) Everything must be 

 clean, the cows, the clothes of the milkers, the milking 

 place, and the utensils. (4) The milk must be quickly 

 cooled after milking and be kept at a low temperature. 

 (5) A bacterial count must show very few bacteria in 

 the milk. (6) The milk must have a large percentage 

 of butter fat. 



Whether one runs a dairy or keeps a single family 

 cow, it ought to be his endeavor to produce milk of such 



