70 FOWL CHOLERA 
-Geographical distribution. Fowl cholera seems to be widely dis- 
tributed in Europe and it has been found in many places in the 
United States and in Canada. In Germany it is the cause of heavy 
losses among poultry. In 1903 it is reported to have killed over 
48,000 fowls and 23,000 geese, besides other poultry. 
Etiology. Fowl cholera is caused by a specific bacterium, Bact. 
cholerae-gallinarum (Bacillus (bipolaris) avisepticus, Pasteurella 
avium), which is not distinguishable morphologically or in its cultural 
manifestations from the other members of the Pasteurella. Accord- 
ing to Gertner, it will remain alive in manure for at least three 
months. It is reported to live in putrefactive carcasses and in garden 
soil for an equal length of time. Kitt states they resist freezing for 
at least 14 days. Natural infection usually takes place by ingestion. 
The period of incubation is placed by European writers at from 18 
to 48 hours. In the case of 40 fowls inoculated by Salmon, it varied 
from 4 to 20 days, the average period being 8 days. Ward fed viscera 
of dead fowls to 10 healthy ones. They died in from 24 hours to 6 
days. 
Symptoms. The symptoms described for this disease in Europe 
differ somewhat from those reported by Salmon. The appetite is 
often affected and occasionally the fowls continue to eat almost to the 
time of death. The earliest indication of the disease is a yellow col- 
oration of the urates. In health, these are a pure white though 
they are frequently tinted with yellow as the result of disorders 
other than cholera. 
Occasionally the first symptom is a diarrhea in which the excrement 
is passed in large quantities and consists almost entirely of white 
urates mixed with colorless mucus. 
Very soon after the first symptoms appear the bird separates itself 
from the flock, it no longer stands erect, the feathers are roughened, 
the wings droop, the head is drawn- down towards the body and the 
general outline of the bird becomes spherical or ball-shaped. At this 
period there is great weakness, the affected bird becomes drowsy and 
may sink into a sleep which lasts during the last day or two of its life, 
and from which it is almost impossible to arouse it. 
The crop is nearly always distended with food and apparently 
paralyzed. There is in most cases intense thirst. If the birds are 
aroused and caused to walk, there is at first an abundant discharge of 
excrement followed at short intervals by scanty evacuation. 
