CHAPTER XxX 
INFECTIOUS DISEASES OF CANARY BIRDS 
Infectious diseases of canary birds cause heavy losses in breeding 
establishments where hundreds of birds are kept in close contact 
with one another. These conditions, and the occasional introduction 
of breeding stock furnish favorable circumstances for the spread of 
disease, and severe losses occur. The literature contains references 
to a number of infections chiefly observed in Germany where canary 
breeding attains considerable importance. Careful comparison of 
the descriptions of canary bird infections indicates that most of those 
described fall into one of two groups. One, designated infectious 
necrosis is caused by a member of the hemorrhagic septicemia group, 
and another is caused by B. paratyphosus B. 
INFECTIOUS NECROSIS OF CANARIES 
Synonyms. Bird fever, canary fever, septic fever and bird 
plague. 
Characterization. The disease is an infection chiefly distin- 
guished by the presence of necrotic lesions in the spleen and liver. 
History. The disease has been described by a number of writers 
including Rieck, Wasielewski and Hoffman, Pfaff, Zwick, Miessner 
‘and Schern, Zeiss, and Binder. The last two writers independently, 
have thoroughly reviewed the literature of canary bird diseases. 
Doubtless the diseases observed by Kinyoun and by Ziirn are the 
same, and in the opinion of Zeiss the one observed by Kern is 
identical. On the other hand, Binder withholds decision as to 
whether or not Kern’s disease is really the one in question. Most 
of the writers have refrained from giving the disease a name, but 
Miessner and Schern suggested the name infectious necrosis. 
Etiology. The organism causing the disease is a non-motile rod 
measuring from 1.5 to 2.5 microns long and .5 to 1. micron broad. 
Occasionally larger forms are observed. The organism is Gram 
negative and shows bipolar staining. Surface colonies on agar are 
grayish in color, appear distinctly granular and are about the size 
of a pinhead. No growth occurs on plain potato, but when this 
medium has been rendered alkaline a slight brownish colored layer 
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