636 



STATE BOARD OF AGRICULTURE. 



TABLE v.— SHOWING THE APPEARANCE OF BACT. ABORTUS AGGLUTININS IN A 

 COW'S UDDER AFTER THE INTRODUCTION OF A CULTURE OF BACT. ABORTUS. 



(Agglutination reaction when various quantities of fore millc were added to the test tubes containing 



bacterial suspension.) 



(a) 5 cc. of a 48 hour broth culture of Bad. abortus, a mixture of strains A, I and III were inoculated 

 into the milk cistern of the right front quarter immediately after milking. 



It seems that the appearance of antibodies in the milk soon after the 

 introduction of a pure culture into the milk cistern would be sufficient 

 grounds for concluding that, conversely, the appearance of agglutinins 

 in the milk would indicate a Bact. abortus infection. This might be a 

 local infection of the udder or it might be due to an infection in which 

 the antibodies present in the blood stream appear in the milk by diffusion 

 from the blood. 



That the appeara.nce of Bact. abortus antibodies in the milk indicates 

 an infection of the cow's udder and not diffusion of the antibodies from 

 the blood stream is indicated in Table I where there is apparently no 

 connection between the antibodies of the blood stream and those of the 

 milk. In some instances milk having a negative or weak antibody con- 

 tent was taken from cows having a strong blood reaction and vice versa. 



Another fact which shows that the antibodies present in the milk do 

 not come from the blood stream is brought out in Table II where it is 

 found that the antibody content of the milk may vary from quarter to 

 quarter. If the antibodies had their source in the blood stream the 

 milk from each quarter should be expected to have about the same con- 

 centration of antibodies. 



Table VI gives the history of milk from a cow with a record of fre- 

 quent abortions. As shown in the table, the isolation of Bact. abortus 

 from the milk and the results of guinea-pig inoculation prove the pres- 

 ence of this bacterium, as indicated by agglutination reactions. 



