STERILITY 127 



that in 1908 there were fifteen per cent abortions, in 1909 

 twenty-five per cent, in 1910 five per cent, and in 1911 

 two-and-one-half per cent of abortions. The carbolic 

 treatment was begun in December, 1909. It is recom- 

 mended that infected males be treated in the same manner. 1 



120. Diagnosis of contagious abortion. This disease 

 is so widespread and causes such serious consequences 

 when once well established in a herd that it is often of 

 the greatest importance to be able to detect its presence 

 in animals, even those which are not at the time pregnant. 

 Various attempts have been made with greater or less 

 success to secure a reliable diagnostic agent which would 

 make it possible for the breeder to know which animals 

 in his herd are infected with the germ of contagious abor- 

 tion and thus be able to separate the infected individuals 

 from those which are healthy. 



The first substance of this character to be used was 

 similar to tuberculin and mallein. The name of " abor- 

 tin " was given to this substance by MacFadyean and 

 Stockman. This material was to be injected into the 

 circulation of the cows of a herd. The infected cows 

 showed a considerable rise in temperature following the 

 infection. The healthy cows showed but little or no 

 increase in temperature. Briill 2 at Vienna, after testing 

 this method on a large number of cows, concluded that 

 abortin was an unreliable diagnostic agent for determining 

 the presence of contagious abortion in cattle. Other 

 investigators have reported similar unfavorable results 

 from the use of this material. 



1 See also Good, Kentucky Experiment Station, Bui. No. 165 ; 

 Surface, Kentucky Experiment Station, Bui. No. 166 ; MacNeal 

 and H. W. Mumford, Illinois Experiment Station, Bui. No. 152. 



2 Briill, "Berl. Tierartzt Woch.," Bd. 27, pp. 721-727. 



