Comparison of infrared, electronic digital and mercury-inglass thermometers: 2. Red sokoto goats

Abstract

Forty eight (male=8; female=40) adult Red Sokoto goats were used in an experiment to compare accuracy of different thermometers. Body temperature (BT) was concurrently measured with electronic digital (ED), mercury-in-glass (MG) and infrared (IR) thermometers. ED and MG thermometry was taken via the rectum (TEMPd and TEMPa respectively) while the IR thermometer was used on the opening of the rectum (TEMPiR) and forehead (TEMPiH). The data were subjected to analysis of variance and Pearson correlation analysis. Scatter diagrams were plotted to generate R squared for the relationships between the readings of the thermometers. Thermometer type had significant (P<0.001) effect on BT in RS goats. TEMPd was similar (P>0.05) to TEMPa, but the duo were significantly higher than TEMPiR and TEMPiH. BT from IR thermometer on the forehead was significantly lower than at the opening of the rectum. There was strong positive significant (P<0.001) correlation between TEMPd and TEMPa (r=0.958). TEMPd and TEMPa had significant (P<0.001) correlations with TEMPiR (r=0.519 and r=0.562 respectively), but not (P>0.05) with TEMPiH. Linear regression of TEMPd with TEMPa, TEMPiR and TEMPiH yielded R2 of 0.918, 0.269 and 0.040 respectively. Deviations from TEMPd obtained were 0.23, 0.91 and 1.69oC for TEMPa, TEMPiR and TEMPiH respectively. The use IR thermometer on the forehead of RS did not yield similar reading compared to other thermometers. Temperature measurement with IR thermometer on the opening of the rectum of RS goats seems to be more accurate than on the forehead.

Keywords: rectal temperature, heat stress, health, welfare, diagnosis