Contagious Abortion. 419 



aborted, and later, cows in the same herd aborted. The owner 

 kept the matter secret and sent his cows to a neighbor's bull for 

 service, with the result that for two years abortion prevailed 

 among the cows served by this bull. 



J. R. Jansen reports that a cow brought from an infected farm, 

 for fattening purposes, proved to be pregnant and finally aborted, 

 and that 24 of the pregnant cows on the same farm aborted in 

 the same year. 



Morck relates how a cow that had aborted a fortnight previously 

 was taken to a farm where abortions had never been known. 

 She aborted during her next gestation and so did the rest of the 

 herd, 9 in number. 



Christensen records the occurrence of a general abortion in a 

 previously healthy herd, members of which had been sent for 

 service to the bull of a neighboring aborting herd. 



Nygaard reports that a bull from a healthy herd, but which 

 had been allowed to serve some cows from a neighboring infected 

 herd, was sold to go on a previously healthy farm, where he was 

 put to 14 cows only. Of these 12 aborted, and the complement 

 of the herd, beyond the 14 cows, put to another bull, remained well. 



In each of these cases the environment of the animals and the 

 conditions remained the same, the one appreciable cause of the 

 outbreak being the contact with an animal from an aborting herd. 



Experimental Infection. Braiier led the way by transferring 

 in 1 1 instances the vaginal mucus of aborting cows to the vagina 

 of healthy ones. The resulting abortions occurred from the gth 

 to the 2ist day after inoculation. I^ehnert repeated this on two 

 cows, the abortions taking place on the twelfth and twentieth days 

 respectively. Trinchera transferred the purulent vaginal 

 mucus of an aborting cow to the vaginae of healthy ones, deter- 

 mining in the latter, in 9 to 13 days, abortion attended by suppu- 

 rating vaginal catarrh. He secured similar results by using the 

 material scraped from the surface of the chorion of an immature 

 foetus. 



The Scottish Commission (Woodhead, McFadyean and Aitkin) 

 placed a healthy pregnant cow in an aborting herd, and on two 

 successive days lodged in her vagina for twenty minutes a piece 

 of cotton wool soaked in the vaginal mucus of a recently aborted 

 cow. Within a iflonth abortion threatened, and on the seventieth 

 day a seven-months calf was dropped. 



