254 DISEASES OF DOMESTICATED BIRDS 
multiplied at the places in question. The larger ones consist of 
clumps of bacteria surrounded by necrotic cells. The largest 
nodules consist of a number of smaller ones united together. 
The presence of the organism in the heart blood is not always 
demonstrated microscopically or by culture. 
Diagnosis. The disease can. be recognized only by the char- 
acteristic lesions observed at autopsy. 
Treatment. No medical treatment is available. 
Prevention. General sanitation and isolation as recommended 
in paratyphoid B infection is suggested. 
INFECTION IN CANARIES CAUSED BY B. PARATYPHOSUS B 
Synonyms. Septic fever in cage birds. 
Characterization. The disease is characterized by enlargement 
of the spleen with enteritis and is caused by B. paratyphosus B. 
History. The disease was described by Joest in 1906 and has 
been encountered later by Gilruth, Pfeiler, Adam and Medler, Man- 
ninger and by Binder. The latter writer and also Zeiss have sum- 
marized the work of earlier students of canary bird infections. 
Etiology. The organism isolated from the birds is a short 
plump rod 2 to 4 microns long and % to 1 micron broad with 
rounded ends. It is actively motile and Gram negative. Flagella 
may be demonstrated by Léoffler’s method, but with all care, it is pos- 
sible to demonstrate one flagellum only on the end of the rods. The 
organism in fresh smears from heart blood or organs often shows 
bipolar staining. 
Growth on agar, gelatin, bouillon, blood serum and potato is the 
same as that of cultures of B. paratyphosus B and B. supiestifer. 
Neither can differences be discovered between the growth of these 
cultures and the canary strains on Drigalski and Conradi or on 
Endo’s fuchsin agar plates. 
In all strains, milk becomes brightened and yellowish colored 
after 8 days. After 14 to 20 days it becomes markedly yellow and 
transparent. After standing in the incubator for a longer time it 
becomes thickened, viscid and yellowish brown in color. Acid and 
gas are produced in dextrose, arabinose, rhamnose and zylose but not 
in lactose, saccharose, and raffinose. Indol is not produced. 
The organism agglutinates to B. paratyphosus B serum and para- 
typhoid B cultures of human origin agglutinates to serum prepared 
from the canary strain. 
