Fowl Cholera. 87 



& Angeloff showed that by the use of swine plague serum the opsonic 

 index is not only raised for swine plague but also for the bacteria of 

 hemorrhagic septicemia of cattle and fowl cholera. 



The polyvalenee should be considered here in a different sense from that applied 

 in the Wassermann-Ostertag 's polyvalent swine plague serum (see swine plague). 



The very close morphological resemblance of the bipolar 

 bacilli from the various sources, the similarity of the cultures in 

 their principal cultural characteristics, the great similarity of 

 the pathological processes produced by them, the possibility 

 of intertransmissibility to the different species of animals, like- 

 wise the common im m unizing properties, indicate that the 

 bipolar bacilli belong to one species of bacteria, while the few 

 deviating characteristics such as the variance of virulence are 

 only characteristics peculiar to the different strains or varieties. 

 The bacteria which probably developed from a common strain 

 originally have undergone modifications in the bodies of the 

 different species of animals by adapting themselves to exist- 

 ing environments similar to that which occurs in other species 

 of bacteria, and which may also be produced artificially. On 

 the other hand, the differences in the pathological processes in 

 the various diseases may be satisfactorily explained by the 

 special characteristics of the different animal species. The 

 close relationship of the causative factors of the several dis- 

 eases brings the affections produced by them into closer rela- 

 tion. Moreover, the similarity of the etiological factors also 

 indicates uniformity in methods to be used in the control of 

 these diseases. 



Literature. Hueppe, B. klih. W., 1886, 753.— Ligni^res, Bull. 1900, 329, 

 (Lit.).— Kitt, Hb. d. p. M., 1903, II, 559, (Lit.). 



(a) Fowl Cholera. Cholera Gallinarium. 



{Fowl typhoid; Pasteurellosiis avium, Cholera des poules 

 [French]; HUhner cholera [German]; Cholera 

 ,, dei polli [Italian].) 



Fowl cholera is an acute, contagious and usually an epizo- 

 otic affection of fowls, particularly of chickens, geese aiid 

 ducks, and is manifested in a general infection associated with 

 a profuse diarrhea. It is caused by a bacterium of the type 

 of the hemorrhagic septicemia organism, the bacillus avi- 

 septicus. 



History. This dangerous fowl plague was described by veter- 

 inarians as early as the 18th century, and in the middle of the last 

 century some of the authors (Benjamin, 1851, Delafond & Renault, 

 1851, and Hering, 1858) have recognized its contagious nature and 

 also substantiated it experimentally. Perroncito (1878) and also Sem- 

 mer described a diplococcus as the cause of the disease which they 

 constantly found in the blood of chickens dead of the disease. Toussaint 



