Fowl Cholera, Fowl Typhoid and Fowl Plague 113 



that considerable work has been done upon fowl plague, com- 

 paratively little is known about it. The following notes are 

 gathered from such literature as is at hand. 



Etiology. — No definite organism has ever been isolated in 

 connection with this disease. Depperich ^ stated (1907) that 

 all the then available evidence indicated that it is caused by 

 an ultra-microscopic, filterable virus. Russ ^ states that the 

 blood from cases of this disease is extremely virulent, being 

 fatal when given in such extreme dilution as 1 to 1,000,000,000. 

 The virus of this disease appears to be in some way attached 

 to or included in the red blood corpuscles. By centrifuging 

 out these corpuscles it is possible to remove a large portion 

 of tlie virus from the blood. Landsterner ^ performed cer- 

 tain experiments which indicated that the causative organism 

 may be a protozoon associated with the blood corpuscles. 

 In this respect the causative factor in the disease appears to 

 show some resemblance to the filterable virus of hog-cholera, 

 according to recent work.^ 



Diagnosis. — Fowl plague is known to affect chickens, tur- 

 keys, guinea-fowl, geese, pheasants, and many wild birds. 

 The lesions of the disease resemble those produced by phos- 

 phorous poisoning.^ The surface of the heart may be covered 

 with small blood clots (ecchymoses) . It can be distinguished 

 from fowl cholera by the presence of hemorrhages under the 

 epicardium and an exudate in the pericardial cavity. 



1 Depperich, C. H., Fortsch. Vet. Hyg. Bd. 4, pp. 217-250, 

 1907. 



2 Russ, V. K., Arch. Hyg. Bd. 59, pp. 286-312, 1906. 



5 Landsterner, K., Centralb. f. Bakt., etc., Abt. 1, Bd. 38, pp. 

 540-542, 1906. 



* For example : 



King, W. E., and Hoffman, G. L., "Studies on Hog Cholera — 

 Spirochoeta suis. Its Significance as a Pathogenic Organism." 

 Jour. Infec. Dis., Vol. 13, pp. 463-498, 1913. 



5 Freese, Dent. Tierarztl. Wchnschr. Bd. 16, pp. 173-177, 1908. 



