48o THE SPIROCHETES 



laboratory in rats or white mice, being passed from animal to animal at appropriate 

 intervals. The most convenient and economical way to maintain them is to bleed the 

 rats forty-eight hours after inoculation and keep the blood in the icebox for five 

 days before inoculation. The relapsing fever spirochetes live for one to two weeks 

 when the citrated or defibrinated blood is preserved at a low temperature. At 37° C. 

 they undergo degeneration within three to four days. On suitable culture media they 

 can be maintained if transferred to fresh medium every five to seven days (see p. 472). 



The organisms causing fevers of geese' and chickens^ were given the names 

 Spirochaeta anserina and S. gallinartim,^ respectively. Various birds can be infected 

 with one or the other organism, however, and it is not improbable that gallinarum 

 is the same species as anserina. If so, the species name of the fowl spirochete becomes 

 Treponema anserinum. The organism produces an acute febrile disease, with loss of 

 appetite, diarrhea, and finally emaciation, which usually kills the bird within a few 

 days. It is present in the circulation until death. The spirochetes are taken up by 

 phagocytes toward the end of the attack, as shown by Cantacuzene'' in geese and by 

 Levaditi,^ Marchoux, and Salembeni^ in chickens. 



Spirochetes of the relapsing fever type are also found in cattle, sheep, horses, and 

 monkeys, and they closely resemble those causing relapsing fever of man. T. theileri^ 

 of cattle is transmissible to horses and sheep, and it is probable that the spirochetes 

 found in the blood of sheep {T. ovinumy and horses (T. equi) are identical with 

 T. theileri. T. theileri is of doubtful pathogenicity since it produces no symptoms in 

 normal animals. 



The difference between T. recur rent is and T. anserinum was demonstrated by 

 Gabritschewsky,^ in 1898, who showed that the blood of immune geese kills T. an- 

 serinum within a few minutes at 37° C. but has no effect upon T. recurrentis, while 

 the blood of convalescents from relapsing fever kills the recurrentis but not the an- 

 serinum. Species differences are also indicated by pathogenicity tests. Novy and 

 Knapp^ thought that the organism of American relapsing fever could be differentiated 

 from those of African tick fever and Bombay fever not only by pathogenic properties 

 but also by morphological characteristics. The difference in animal reactions be- 

 tween the American strain {T. novyi) and the European {T. recurrentis) and African 

 {T. duttoni) strains is considerable. The novyi is only mildly pathogenic for monkeys 

 and non-pathogenic for rats, the duttoni is usually fatal to monkeys and may cause 

 death even in rats, and the recurrentis is pathogenic but not fatal to animals. 



Schellack,'" who carried out serological tests with monovalent immune sera specific 

 for each strain, believed that the organisms causing the European and American re- 



' Sakharoff, N.: Ann. de VInst. Pasteur, 5, 564. 1891. 



= Marchoux, E., and Salembeni, A.: loc. cit. •* Caiitacuzene, J.: ibid., 13, 529. 1S99. 



3 Swellengrebel, N. H.: ibid., 21, 582. 1907. sLevaditi, C: ibid., 18, 511. 1904. 



*Laveran, A.: Compt. rend. Acad, des sc, 136, 939. 1903. 

 7Theiler, A.: /. Comp. Patli. & Thcrap., 17, 47. 1904. 

 * Gabritschewsky, G. : Ann. de VInst. Pasteur, 10, 630. 1896. 

 9 Novy, F. G., and Knapp, R. E.: loc. cit. 



'oSchellack, C: Arb. a. d. kaiserl. Gesundlteitsamte, 30, 351. 1909; Centralbl. f. Baktcriol., Abt. 

 I, 46, 486. 1908. 



