EXPERIMENT STATION BULLETINS. 



635 



10, 1914, using Bad. abortus as antigen. Thirty-five c.c. of a 48-hour 

 broth culture of Bad. abortus were introduced into the right rear 

 quarter after it had been milked dry. As shoAvn in the table, the 

 agglutinins had appeared in the right rear quarter the following day 

 and soon spread to the other quarters. This spreading was probably 

 brought about by the organism being carried from quarter to quarter 

 upon the hands during milking. After the cow freshened the reaction 

 was seen to die out gradually. 



TABLE IV.— SHOWING THE APPEARANCE IN MILK OF AGGLUTININS FOR BACTERIUM 

 ABORTUS AFTER THE INTRODUCTION INTO THE COW'S UDDER OF A PURE CUL- 

 TURE OF BACT. ABORTUS, (a) 



(Agglutination reaction at middle of milking, when various quantities of milk were added to test tubes 



containing bacterial suspension.) 



(a) In all cases, unless otherwise stated, the milk was taken a little before what was estimated to 

 be the middle of the milking. 



(b) 35 c.c. of a 48-hour broth culture of Bact. abortus introduced into right rear quarter. 



(c) Cow calved. Bull calf died on Mar. 13, 191.5, owing to undigested curd. Reaction of blood of 

 calf; — agglutination; -fcomplement-fixation test. 



In Table V we have the record of another cow treated in much the 

 same way as the cow in Table IV, except that a smaller amount of Bad. 

 abortus culture was introduced into the right front quarter where it 

 produced the agglutination reaction indicating infection. The infection, 

 however, had not spread to the other quarters when last tested, though 

 it remained strong in the right front quarter. Cultures used in this 

 test may have lost some of their virulence having been grown under 

 laboratory conditions for over a year. 



