160 Report of the Department of Bacteriology of the 



quarter on February 7, 1911, was lost because of its failure to grow. 

 A culture of similar appearance isolated in May, 1911, from the 

 right front quarter, which may or may not have been the same, 

 gave the group number M. 211.2223032 but showed no tendency 

 to form chains. 



The organism present in the left hind quarter was a yeast with 

 the group number 212.2332033 and occurred in practically pure- 

 culture in all of the plates made from this quarter. A search for 

 this organism made in December, 1913, by technique similar to 

 that used by Wilson, failed to show this organism present in the 

 left hind quarter though scattered colonies of a similar yeast made 

 their appearance on plates made from other quarters of the udder. 



None of these cows show as extreme conditions as those noted 

 by Breed and Stidger 42 in their similar studies. They examined 

 samples of milk from three apparently normal cows selected at 

 random from a herd in Gottingen, Germany, daily for a period of 

 four weeks. One cow (No. 54) gave an average count of 535,000 

 cells per cubic centimeter while another (No. 55) gave an average 

 count of 2,070,000 cells per cubic centimeter. This latter cow 

 showed marked fluctuations in the number of cells present in her 

 milk, the numbers varying from 885,000 to 5,975,000 cells per cubic 

 centimeter. 



In marked contrast to this, Cow No. 56 showed very few cells 

 present in the milk of three quarters of her udder while the milk 

 of the fourth quarter showed a cell content fluctuating between 

 230,000 and 1,110,000 cells per cubic centimeter. The contrast 

 between the milk of these two cows was so great that " if the whole 

 number of cells discharged by the right hind quarter of Cow 56 

 in the 36 milkings tested had been discharged at a single milking 

 and that in a liter of milk instead of in the If liters actually secreted, 

 the number of cells would have been approximately 2,000,000 

 per cubic centimeter, that is a number which was the average number 

 of cells found in the milk of Cow 55. In the extreme case, one 

 quadrant of Cow 55 liberated almost as many cells at a single milking 

 as the hind quarter of Cow 56 would have done in the half of an 

 entire lactation period if the same low rate found in the period tested 

 prevailed." No bacteriological examinations of the udder were 

 made for any of these cows. 



42 See footnote 1. 



