Reference interval for rectal temperature in healthy confined adult cats
The normal rectal temperature range for a cat has long been considered to be between 100.0 and 102.5⁰ F, but there’s little evidence to substantiate that range.
A research team led by Maddie’s Shelter Medicine Program at the University of Florida professor Dr. Julie Levy measured rectal temperatures of 200 healthy cats in homes, shelters, and veterinary hospitals.
In the study abstract, the authors concluded the commonly used reference range is inaccurate:
A range of 36.7–38.9°C (98.1–102.1°F) should be considered the new reference interval for healthy adult cats for rectal temperature measured indoors in climate-controlled conditions. This range is lower than commonly reported. Use of previously published ranges could lead to overdiagnosis of hypothermia or underdiagnosis of mild pyrexia.
In another study, the research team looked at the accuracy of methods of taking cats’ temperatures other than rectally. They found:
Bland–Altman analysis revealed poor agreement between NIRT and rectal thermometry. The mean NIRT measurements ranged from 0.7–1.3°C below the mean rectal measurements, but the effect was not consistent; NIRT measurements tended to exceed rectal measurements in hypothermic cats and fall below rectal measurements in normothermic and hyperthermic cats.
The study abstracts are available at the links below; subscribers can read the complete study for free, while non-subscribers can access it for a fee, at the same link.
Levy JK, Nutt KR, Tucker SJ. Reference interval for rectal temperature in healthy confined adult cats. J Feline Med Surg 2015 17:950-952.
Nutt KR, Levy JK, Tucker SJ. A comparison of non-contact infrared thermometry and rectal thermometry in cats. J Feline Med Surg 2015 Jul 24. pii: 1098612X15596564.