Infectious Abortion of the Cow ^gy 



jugular vein of a pregaant cow, which aborted 90 days later, and 

 in the exudate upon the afterbirth he found the abortion bacilli. 

 In this connection he states: "Since that time we have made 

 more or less extensive experiments with cows, sheep, goats and 

 rabbits, and produced abortion in this way. ' ' One may infer 

 from these experiments that, while it is not proven that the 

 abortion of the mare is identical with that of the cow, he suspects 

 that such may be the case, and that, consequently, when con- 

 tagious abortion breaks out among cows, other pregnant animals 

 should be protected against exposure. 



Having satisfied himself that the bacilli could be carried to the 

 uterus through the blood. Bang suspected the possibility of the 

 organisms reaching the uterus through the alimentary canal 

 also. He administered |4^ of a liter of an artificial culture of the 

 bacillus in bouillon serum to a pregnant cow, on the 12th of June, 

 and ou the 7th of Sept. he gave her a quantity of exudate from 

 an aborted cow. She gave birth to a living calf on the 26th of 

 November, 80 days after having been fed upon the exudate. In 

 the typical exudate upon the afterbirth, there were abundant 

 bacilli. Ivater he repeated this experiment under conditions 

 which, he claimed, "excluded the possibility of infection in 

 any other way than through feeding." The heifer aborted 56 

 days later. 



How the possibility of infection by other avenues was excluded 

 in this experiment does not appear. If the bouillon, exudate 

 and cotyledons were given to these animals as a drench or mixed 

 with food, we see no reason why portions of the liquid escaping 

 from the mouth might not soil the food or bedding, to later be 

 accidentally moved backward and reach the posterior part of the 

 stall, making it possible for the infection to gain entrance through 

 the vulva. If the material were given in any other way than in 

 an impermeable capsule, the mouth would inevitably become in- 

 fected and the cow, in licking her posterior parts, as she habitu- 

 ally does, could transfer the micro-organisms to that portion of 

 her body, whence they might enter the vulva. 



Even should the abortion bacilli pass into the alimentary tract, 



we have no evidence that they may not resist the action of the 



digestive fluids, appear in the feces and enter the vulva. The 



mere assumption that the bacilli may be taken up from the in- 



32 



