Noninvasive temporal artery thermometry as an alternative to rectal thermometry in research macaques ( Macaca spp.)

Obtaining an animal's body temperature is essential for the assessment of its clinical status. For many species, rectal thermometry is the technique used most often; however, this method in macaques typically requires sedation or considerable physical restraint. A noninvasive and inexpensive temporal artery (TA) thermometer was evaluated as an alternative method for collecting body temperature measurements from macaques used in neuroscience research. Rectal and arterial temperatures were obtained from 86 macaques (mean age, 10.2 y) that had received ketamine (10 mg/kg IM) or Telazol (5 mg/kg IM); the arterial measurements were taken from behind the right ear. In addition, arterial temperatures were measured behind both ears in a cohort of awake, chaired macaques with cephalic restraint pedestals only (n = 8) or with cephalic restraint pedestals and recording chambers (n = 14). Within-subject repeatability for TA thermometry and agreement between rectal and arterial temperature measurements were assessed by using the Bland-Altman method. Temperature measurements indicated that values from TA thermometry were lower than those from rectal thermometry by 1.57 °C with a 95% agreement limit of ± 1.27 °C. Results show satisfactory repeatability with TA thermometry and agreement between arterial and rectal temperatures, demonstrating that TA thermometry can be a valuable tool in conscious, chaired macaques with restrained heads.