BACILLI OF THE COLON-TYPHOID-DYSENTERY GROUP 693 



B. ABORTUS EQUI AND INFECTIOUS ABORTION OF HORSES. The infec- 

 tious abortion of horses and cattle has interested veterinary bacteriolog- 

 ical workers for a great many years, since, in both cases, the diseases have 

 been the cause of much economic loss. There is, however, considerable 

 confusion in the minds of general bacteriological workers concerning 

 the various organisms that have been described in connection with these 

 diseases and there seem to be two very distinct types associated with the 

 condition in different animals, one of them belonging to the paratyphoid 

 or hog cholera group, the other apparently having nothing to do with 

 these organisms, biologically. We refer to them both in this place, 

 however, because anyone looking up the B. Abortus in this book would 

 desire to have a definite statement concerning the status of the bac- 

 teriology of the diseases in general. The idea that abortion of domestic 

 animals was an infectious disease really originated with breeders and was 

 first suggested to scientific workers by Flandrin in 1806. 31 Nothing 

 positive from the bacteriological point of view came out of this until 

 1897 when Bang 32 described an organism which he isolated from cows 

 which had aborted. There seems to be little question about the 

 ability of Bang's organism to cause this disease in cattle. The 

 description of the Bang organism which is generally spoken of as 

 B. Abortus Bovis will be found in another part of this book. 



Soon after Bang's announcement, a British Commission investi- 

 gated the same subject with a view of finding out whether the abortion 

 on horse farms in England were due to the same bacillus, but they 

 could not confirm this. Ostertag 33 also investigated the same subject 

 in 1900 in Germany, but could not confirm the original suggestion of 

 Bang that his bacillus caused abortion in horses as well as in cattle. 

 In 1903, Smith and Kilborne 34 described a bacillus belonging definitely 

 to the hog-cholera group which they had isolated from the vagina of 

 horses that had aborted, and which they held responsible for the disease. 

 De Jong 35 confirmed these findings and was able to produce the disease 

 in mares by intravenous injection. Numerous other investigations 

 have been made since then, a recent one by Gminder 36 confirming every- 

 thing claimed by Smith and Kilborne in the beginning. Gminder isolated 



31 Flandrin, quoted from Gmmder, Arb. a. d. Reichsgesundheitsamte, 52, 1920, 

 113. 



32 Bang, Zcit. f. Tier. Med., 1, 1897, 241. 



33 Ostertag, quoted from Gminder, loo. fit. 



34 Smith and Kilborne, Bull. No. 3, IT. S. Bur. Animal. Ind., U. S.'Treas. 



35 De Jong, Cent, f . Bakt., 67, 1912, 148. 



36 Gminder, Arb. a d. Reichsgesundheitsamte, 52, 1920, 113. 



