TEST FOE BACTEEIUM PULLOEUM INFECTIOI^ IN FOWLS. 15 
In a field test on 231 birds made simuitaneousl}' with the agglutina- 
tion test, the intradermal test at 38 hours failed to detect one case 
reported positive to the other test. In a second flock of 50 birds in 
which the two tests Y\'ere compared, the intradermal test when read 
at 46 hours failed to indicate one case that was detected by the agglu- 
tination test. Another group of about 100 birds tested under un- 
favorable conditions gave less satisfactory^ results. 
Forty-seven birds that had been tested by the agglutination methocl 
by the Connecticut Agricultural Experiment Station in the field were 
purchased for experiments with the intradermal test. Of these, 1-0 
had given positive reactions to the agglutination test and 7 doubtful 
reactions. There was complete agreement between the agglutination 
test, the intradermal test, and autopsy findings in TO per cent of the 
cases. The agglutination test reported positive in 3 cases, or T per 
cent, was not confirmed by the intradermal test nor by the autopsy 
findings. The result of the intradermal test was negative in 2 cases, 
or 5 per cent, when it was not confirmed by the positive agglutination 
test and autopsy findings. Thus the percentage of absolute failures 
of each test was small and very similar for both tests. 
Autopsy does not furnish an absolute standard for comparing the 
accuracy of tests. Seventy-two per cent only of naturally infected 
birds that had reacted to one or both tests were found on autopsy to 
be unmistakably infected. 
The intradermal test detected the presence of infection in 1 of the 
81 control birds injected in connection with the tests in the laboratory 
on artificially and naturally infected birds. 
In a field trial not made by the writers, 1,301 birds were tested 
mtradermally and 78 reacted. Of these 70 reacted to the agglutina- 
tion tests made subsequently. 
The intradermal test has already shown sufficient promise to war- 
rant further extensive trials in the field in comparison with the 
agsflutination test. 
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