RAPID RECTAL TEMPERATURE RECORDING OF PIGS

The objective of the study was the development of a rectal temperature measurement system for nse in large pig herds. The requirement was th at the new, method should have the same accuracy as liquid-based ol so -called digital thermometers, but with a recording time of only a few seconds. In addition, up to several thousand temperature measurements needed to be stored for later statistical processing. The technical sp ecifications of the thermometer evaluated were as follows: (i) the tim e constant of the NiCr-Ni thermo-element was 0,45 seconds in water and 3.5 seconds in air; (ii) the range of the temperatures to be measured was between 35 degrees C and 45 degrees C; (iii) a 3.5 digit read-out with 0.1 degrees C precision; (iv) an accuracy greater than + 0.2 deg rees C +/- 0.1; (v) an analogue output of 2.5V at 35 degrees C to 3.5V at 45 degrees C; (vi) a data storage capacity of in excess of 2,000 v alues; (vii) a battery capacity of up to 24 hours, and (viii) an RS232 serial interface to the host computer/data I recorder. This thermomet er was rested on 24 sows and 20 piglets. The reproducibility was less than 0.2 degrees C. The maximal difference between measurements betwee n the reference thermometer was less than 0.4 degrees C, i.e. better t han 1%. The maximum measurement time was 9 seconds, with the mean time of about 5 seconds and a minimum time of 2 seconds.