76 
Journal of Agricultural Research 
Vol. XXVIII, No. 1 
all sugars with the exception of lactose, which remains neutral, with a slight 
tendency toward alkalinity; milk slightly acidified in 5 days. The thermal 
death point is 62$° for 10 minutes; the bacterium lives in both distilled and tap 
water in the dark for over 20 days, but is killed in the same medium in the sun¬ 
light in less than 24 hours; on glass rods the organism retains its vitality in 
the dark for up to 89 hours, but loses it in the sunlight in less than 30 hours; 
resists dry heat to the extent of giving good growth when subjected to 75° C. for 
5 minutes, but fails to give growth when subjected to the same temperature 
for 10 minutes. Killed in dilution 1:1,000 phenol, HgCb, 1: 20,000. Stock cul¬ 
tures show decided loss of virulence after being transferred several generations 
on artificial media. 
ARTIFICIAL INFECTION 
Studies on 38 cases of typhoid, artificially infected per os, by subcutaneous 
inoculation, or through the drinking water, show the incubation period to be 
OUTBREAK- SPR/NO OF/922(APR/L) 
/OSS- 20 OUTOF/OO B/RDS 
CHECKED BY 2 YACC/A/AT/ONS. 
OUTBREAK-MAR. I922 
DOSS /OOUTOFAOS/RDS 
CHECKED BY STOCK MCC/A/E, 
OUTSA 
AFTER J 
LOSS-6 OUT 20 
B/RDS CHECKED 
BYSTOCK YACC/A/E 
NOTAT/OW 
OUTBREAK-MAR. /922 
LOSS - 7 OUT OF200B/RDS 
CHECKED BYAUTOOEHOUS 
YACC/HE. 
I OUTBREAK-MAR./922 
_ V , , /OSS- 7 OUT OF/2 B/RDS 
?n r %7f%r£?Z'n'%'/ gWW^WW**** 
entire /ertg/h. YACC/A/E. 
Except where indicated, /to mferchange 
of stock, eggs, orother contact was 
established 1 between farms during epidemic. 
Fig. 1 . —Map of region in which eight outbreaks of fowl typhoid occurred in the winter 
and spring of 1922. 
from four to six days before definite clinical symptoms appear. Temperature in 
severe cases runs as high as 111.5°, "respiration going as low as 23. The organ¬ 
ism was recovered from the blood current of infected birds in two instances, 
four days after infection and six days after infection. In one instance the or¬ 
ganism recovered was used as an infecting agent of another bird, this bird dying, 
while the original host recovered, having a normal laying rate until accidentally 
injured. There is a slight formation of agglutinins during the early part of the 
disease, demonstrated by Widal, and macroscopic agglutination tests in low 
dilutions. Hematological studies show a reduction of erythrocytes; leucocy- 
tosis, with a decided increase in the polymorphonuclear leucocytes. There is a 
decided lack of coagulability of the blood. The polymorphonuclear leucocytes 
may run as high as 95 per cent while the lymphocytes go down to 5 per cent; 
the erythrocytes fall as low as 1,160,000; the face, comb, and wattles become 
anemic; hemoglobin may fall to 75 per cent. 
