ABSTRACTS 117 



Further Studies of the Presence of and Significance of Agglutinins for 



Bact. abortus (Bang) in Cows' Milk. L. H. Cooledge. 



An application has been made of the complement fixation and ag- 

 glutination tests using B. ahartus (Bang) as antigen and replacing the 

 blood serum usually tested with milk. The two tests, when applied 

 to milk from infected udders have checked closely, with the agglutina- 

 tion test a trifle more delicate and reliable. For this reason only the 

 agglutination test is reported in this work. 



In every instance where milk direct from the udder was found by 

 animal inoculation or cultural methods to contain B. abortus it was 

 also found to agglutinate B. abortus. Antibodies were apparently pro- 

 duced locally due to a local B. abortus injection as in some instances 

 the milk from only one quarter would be positive while in others 

 all four might be positive with a negative blood reaction. In other 

 instances milk from a quarter would agglutinate the organism when 

 the bacterium could not be demonstrated in the milk by animal in- 

 oculation. In these instances the agglutinins may have come from 

 the blood but the indications are that they were produced locally by 

 too shght an infection for the organism to be present in sufficient 

 numbers to cause the disease with the 5 cc. of milk used for inoculation 

 of guinea pigs. 



The antibodies usually considered as accompanying infection by 

 this organism have recently been found in the blood of two men and 

 one woman drinking milk from a herd containing infected animals. 

 In two other instances these antibodies appeared in the blood of men 

 drinking milk that was known to be naturally infected with this organ- 

 ism. This method may prove to be another means of safeguarding 

 certified and unpasteurized milk. 



This material has been submitted to the Journal of Agricultural 

 Research. 



The Behavior of Streptococci of Human and Bovine Origin in the Cow's 



Udder.^ George Mathers. 



Bacteriological observations in many epidemics of acute tonsillitis 

 indicate that the causative organism is a virulent hemolytic strepto- 

 coccus and that the infection is milk-borne. In epidemics in which 

 an infected milk supply is an important factor it becomes necessary 

 to determine the source of the bacteria, and the method by which 

 they gain entrance into the milk. In the instance of epidemic tonsil- 

 litis the question naturally arises whether the udder of the suspected 

 cow becomes infected with human streptococci, or whether the organisms 

 causing the outbreak represent bovine streptococci that have suddenly 

 acquired a heightened virulence for man. From a review of the litera- 

 ture it seems probable that hemolytic streptococci derived from bovine 

 sources are of httle sanitary significance, and the active factors in 



1 This work was made possible by means of a grant from the Winfield Peck 

 Memorial Fund. 



