116 BOVINE OBSTETRICS 



clean, had a healthy location. Strebel looked upon as causes 

 of this abortion, first, tainted food, and second, an infection 

 from a decomposing placenta, from which an agent developed, 

 acting especially upon the gravid uterus. 



This was also Bouley's opinion. He insists that a septic 

 agent results from the decomposing placenta of a cow which 

 aborts, and which, transferred to other pregnant cows, produces 

 abortion (St. Cyr and Violet). 



Already in 1812 Cruzel enumerated infection among the 

 causes of abortion. 



Rueff is of the opinion that abortion is caused by a sort of 

 contagion ; and therefore in his text-book on obstetrics, as far 

 back as 1878, proposes prophylactic therapeutics ; which is still 

 of value to-day and needs but little improvement with regard 

 to more recent investigations. 



Experience taught long ago, that abortion, when once 

 occurring in a stable, may spread and produce abortion among 

 many cows. It was also known that the purchase of cows from 

 an infected stable imported the disease. The manner in which 

 abortion spread in a stable where but one case had put in its 

 appearance, by going from one cow to a neighboring cow, etc., 

 put the stamp of infectiousness upon enzootic abortion, 

 although at that time nothing was known about the contagious 

 agent. 



Briiuer was the first to prove by experiments that the 

 vaginal mucus of cows which had aborted in a stable where 

 enzootic abortion existed, when transferred to the healthy 

 vaginal mucous membrane of other pregnant cows, caused them 

 to abort ; abortion took place in nine to twenty-one days. 

 After abortion he found cocci in the vaginal discharge as well 

 as in the fcetal waters. 



Franck found micrococci in such vaginal mucus, and looked 

 upon them as the infectious material. 



Lehnert obtained the same results as Briiuer. Briiuer 

 later took cotton and saturated it with foetal water and mucus 

 of the vagina of a cow which had aborted twelve hours prev- 

 iously. This cotton was placed for ten minutes into the vagina 



