Immunization. 97 



fowl cholera bacteria into rabbits. After the addition of .5% carbolic 

 acid this is heated for 3 hours at 44° C. Repeated injections of small 

 doses (.5 to 3 cc.) or a single injection of 5 cc. protected guinea pigs 

 and rabbits as well as a hen and a pigeon against a subsequent lethal 

 infection. Rabbits higlily immunized with sterile exudate produce serum 

 of which .5 cc. protected rabbits against a dose of the culture which is 

 fatal in 20 hours. According to the aggressin theory (see page 30) 

 the body is supposed to form an anti-aggressin as a result of the injec- 

 tion of aggressins which destroys the aggressiveness of the bacteria 

 and their unlimited power of multiplication. Huntemiiller, however, 

 found that similar good results may be obtained in rabbits with wash- 

 ings of cholera cultures heated to 44° C. He also learned that the 

 filtrate of exudates was ineffective, and he therefore concurs in his 

 belief with Wassermann and Citron, that in immunization the toxic 

 body substances of the bacteria are the effective agents. Bisanti's 

 experiments suggest also the possibility of a toxin innnunization. This 

 investigator sewed collodium sacs filled with virulent cultures into the 

 abdominal cavity of rabbits and thereby protected them against $t 

 cerebral infection. 



Veterinary Police. Chicken cholera has been recently in- 

 cluded among the diseases requiring compulsory official notifica- 

 tion in Germany, Austria and Hungary. Upon the appearance 

 of the disease the infected premises or in case of a greater ex- 

 tension, localities and even entire townships are quarantined 

 against traffic in fowls. The inland and foreign traffic in fowls 

 as well as the premises of dealers are subject to official super- 

 vision. 



Literature. Eenault, Eec, 1851, 321.— Bering, Spez. Path., 1858, 355 (Lit.).— 

 Perroncito, A. f. Tk., 1879, Y, 22. — Toussaint, Eec, 1879, 946.— Pasteur, C. E., 

 1880, XC. u. XCI.— Zurn, D. Gefliigelkrankh., Weimer 1882.— Kitt. D. Z. f. Tm., 

 1888, XIII, 1; Hb. d. p. M., 1903, II, 543 u. 1904, IV, 969 (Lit. on etiology 

 and immunization).— Lignieres, Bull., 1900, 332, u. 1902, 444.— Klett & Braun, D. t. 

 W., 1904, 545.— Weil, A. f. Hyg., 1905, LII, 412; 1908, LVX, 85.— Ostertag & 

 Ackermann, Z. f. Infkr., 1906, I, 431.— Jungklaus, Diss. Leipzig 1906. 



Other Diseases of Fowl of a Septicemic Character. Various ob- 

 servers have described in the course of the last decade different epi- 

 zootic affection in fowl in addition to chicken pest which simulate 

 chicken cholera more or less. In some of these their identity wit!i 

 chicken cholera was established. Others, however, were shown to be 

 different, while the nature of some of the diseases is doubtful even at 

 the present time. On account of their relatively slight importance and 

 their prevention by other means than immunization for which it is 

 essential to establish the causative agent, the same principles mentioned 

 for chicken cholera are also applicable. Therefore these diseases will 

 only be briefly mentioned here, emphasis being placed on their most 

 important differences from fowl cholera. 



The following diseases are identical wdth chicken cholera: 



Lisi's chicken septicemia (Clin, vet., 1895, 176), and the hemor- 

 rhagic septicemia of ducks and chickens described by Rabieaux (Soc, 

 biol., 1900, 141). 



7 



