BACTERIUM ABORTUS INFECTION OF BULLS 



[PRELIMINARY REPORT) 



By J. M. Buck, G. T. Creech, and H. H. Ladson, Pathological Division, Bureau of 

 Animal Industry, United States Department of Agriculture 



Numerous investigators have called attention to the fact that Bacterium 

 abortus agglutinins and complement-fixing bodies can frequently be dem- 

 onstrated in the blood serum of bulls from abortion-infected herds. Such 

 animals in consequence have frequently been referred to as being sys- 

 temically infected. While the presence of these bodies constitutes strong 

 evidence that abortion infection exists, or has been present, success has 

 been reported in associating positive reactions with the causative infec- 

 tion in so few instances as to have resulted in a certain amoimt of specu- 

 lation regarding the significance of these reactions in male animals. 



Literature, it is true, records no great amount of investigative work 

 in connection with bulls suspected of being infected with abortion disease 

 where the object has been the isolation of the causative microorganism 

 from the organs or tissues of the animals or the demonstration of lesions 

 associated therewith. 



Schroeder and Cotton ^ in investigating this problem describe two cases 

 that came under their observation. They state that one of the bulls at 

 the time of autopsy showed the presence of an abscess involving the 

 epididymis of one testicle from which Bad. abortus was isolated. The 

 other animal was permitted to serve a cow that was considered to be 

 free from abortion disease. Seminal fluid which was recovered from the 

 vagina immediately following the service and injected into numerous 

 guinea pigs produced Bad. abortus lesions in one of the experimental 

 animals. 



Rettger and White ^ describe endeavors to associate the presence of 

 the infection with positive serum reactions in three cases which they 

 studied. In two of the animals neither abortus infection nor pathological 

 changes could be demonstrated. In the third they call attention to the 

 finding of two abscesses or cysts in the region of the groin, near the 

 point of attachment of the scrotum; but from these abscesses they were 

 unable to isolate the abortion organism, thus failing to obtain bacterio- 

 logical evidence of the infection. 



In view of the positive bacteriological findings of Schroeder and Cotton 

 the present writers were prompted to undertake further investigations, 



Journal of Agricultural Research, Vol. XVII, No. s 



Washington, D. C. (239) Aug. 15, 1919 



sf Key No. A-49 



122501°— 19 5 



