88 DAIRY LABORATORY GUIDE 



barn, dairy, and various places of interest. Place in 

 incubator as before and note results. Determine gas 

 fermentation by use of curd test and also by placing 

 sterile bouillon in fermentation tubes. A small test 



Fig. 44. — Shows a plate exposed one-half minute during 

 the process of milking, under cow's udder treated by 

 merely brushing with the hand. Each of the little 

 spots represents a colony of some kind of bacteria. 



tube inverted inside of a large one will answer for a 

 fermentation tube. Add a few drops of milk or 

 cream to be tested and allow to remain at 100° F. 

 for twelve to twenty-four hours, and note amount of 

 gas collected. 



