Agreement study between esophageal and cloacal thermometry or infrared thermography measurements in Eurasian eagle-owl (Bubo bubo)

Abstract

Body temperature is a marker of health or disease in wild birds. In avian species, the most common clinical method for determining body temperature is cloacal thermometry; however, there is little information on how it represents central body temperature in most avian species, including the Eurasian eagle-owl. Also, a less invasive method, such as infrared thermography, may reduce stress during clinical procedures. This study aims to perform a concordance analysis between cloacal thermometry and ocular or pedes thermographic measurements taken from Eurasian eagle owls, comparing them to esophageal thermometry, which is considered a good gold standard for its anatomical arrangement. The study was performed during the clinical procedures carried out on owls at the recovery center hospital. Thermometric measurements (esophageal, cloacal) and thermographic images of the pedes and eyes were documented. The highest correlation was observed when esophageal thermometry values were compared to cloacal thermometry values or eye thermography. The obtained agreement values showed a bias (upper limit of agreement (LoAu)- lower limit of agreement (LoA(2.77 to 0.90), 0.30(2.77 to 0.86), and 0.30(3.62 to 4.16) ol)) of 0.30(0.90 to 0.76), 0.20 C, when esophageal thermometry was compared to cloacal thermometry or thermography values obtained from entire eye, medial canthus of the eye, and pedes, respectively. The cloacal temperature had better correlation and agreement with esophageal thermometry than the thermographically studied sites. The ocular temperature showed a closer agreement with esophageal temperature than with the temperature measured at the pedes. Neither cloacal nor thermographic temperature measurements are concordant with esophageal temperature values (>0.5 ◦C).