656 Diseases of the Genital Organs 



The etiology of calf scours has not been clearly deter- 

 mined. Numerous writers regard it as a specific contagious 

 or infectious disease having one bacillus as the uniform 

 causative agent, to which is frequently added other compli- 

 cating organisms. This is difficult to prove or disprove. It 

 has been noted already that diarrhea is common in abortion. 

 Most investigators of abortion record only their findings re- 

 garding the B. abortus. They state generally that they re- 

 covered the B. abortus from the alimentary tract of the 

 abort, but fail to state whether other bacteria were present. 

 According to our investigations the B. abortus is not as com- 

 mon as some other bacteria in the utero-chorionic space, the 

 fetal alimentary tract, or the alimentary tract of the calf 

 with or without diarrhea. 



For a number of years following the researches of No- 

 card, it was taught that calf scours was due to a bipolar 

 bacillus of the septicemia hemorrhagica group. Later Jen- 

 sen and others taught — and their views were commonly ac- 

 cepted — that the basic cause was a colon bacillus. My col- 

 league, Carpenter, has recently presented strong evidence 

 tending to show that a streptococcus of the viridans group 

 is the most prominent organism present. Micrococci are 

 common, but no connection between them and dysentery has 

 been traced. Carpenter has generally failed to identify the 

 colon organism in the intestinal tracts of fetuses and of sick 

 calves destroyed before death was imminent, but has com- 

 monly recovered in these cases the streptococcus of the viri- 

 dans group. Later when the calf is apparently dying, or 

 has been dead for a few hours prior to the making of cul- 

 tures, the colon organism becomes very conspicuous. It has 

 been frequently asserted without qualification that dysen- 

 tery in calves can be uniformly produced in its typical form 

 by inoculating with the colon organism. My colleagues, 

 Hagan and Carpenter, have repeatedly tried in vain to cause 

 dysentery with this bacterium. This seemed peculiar, espe- 

 cially since Jensen is regularly cited as having proven 

 clearly by experiment the specific character of the bacillus. 

 A critical study of his recorded experiments explains at least 



