168 TUBERCULOSIS 
to eight hours, giving a steady but quite rapid elevation for from 
1 to 8 hours, a continuous high elevation for from 2 to 4 hours, possibly 
longer, and a gradual decline. This is practically constant, be the 
raise moderate or extreme. In rare cases the elevation of the tem- 
perature does not begin for 18 or more hours after the injection. In 
addition to the elevation in temperature there is sometimes a marked 
nervous chill or muscular trembling. This has been referred to as 
the “Organic reaction.”” It is often overlooked by those making the 
test. 
Subcutaneous use of tuberculin. In brief, this method of applying 
tuberculin is as follows: 
“The normal temperature of the animal to be tested must be 
determined. It is recommended that it be taken hourly or every two 
hours for the day preceding the test. 
“The tuberculin is injected subcutaneously, usually in the side of 
the neck. Care must be taken that the syringe is sterile and the 
site of injection should be disinfected. The size of the dose depends 
upon the preparation of tuberculin used, that is, the degree of con- 
centration. 
“Beginning 6 hours after the injection, the temperature should be 
taken hourly, or at least every two hours, for fully twenty-four hours 
after injection. If at that time the temperature is rising it should be 
taken thereafter regularly until it returns to the normal. 
“During the time of testing, the cattle should be kept quiet and 
free from all exposure, and fed normally. 
“Tf a reaction occurs there is a gradual rise of temperature, begin- 
ning usually in from 4 to 10 hours after the injection of tuberculin, 
and continuing for some hours. The rise of temperature forms a curve 
with a maximum varying from 1.5° C. to 5° or 6° F. above the normal 
temperature of the previous day. There may also be an organic 
reaction. If there is a maximum rise of temperature of 1.5° F. with a 
definite curve it is usually safe to consider it a positive reaction. 
Erratic elevations of short duration are to be excluded. In all] cases 
where the rise of temperature with a curve is under 103.5° F. there 
may be doubt as to the diagnosis. All cases that give a temperature 
of 108° F., if appreciably above the preinjection temperatures, should 
be considered suspicious. These cases should be retested afew months 
later using a double dose of tuberculin. 
“Animals advanced in pregnancy and those known to be suffering 
from any other disease or in cestrum should not be tested. All 
