Continuous monitoring of temperature in laboratory animals during inhalation exposure

An automatic system was developed to monitor continuously the colonic temperature of laboratory animals during inhalation exposure to toxic chemicals. It includes: an automatic switchbox, a control circuit, a recorder and a digital voltmeter. The system was calibrated for different temperature ranges and used for a year to assess the effects of household solvents on temperature of Sprague-Dawley rats. Reliable monitoring of temperature in 16 rats was carried out in a sequential manner in the manual mode or in the automatic mode for several consecutive days. Very slight changes (.01 - .02 degrees C) in temperature can be measured with this system.