What is the body temperature of rats? - briefly
The typical core temperature of a rat lies between 37.5 °C and 38.5 °C (99.5–101.3 °F). Small variations occur depending on strain, age, and environmental conditions.
What is the body temperature of rats? - in detail
Rats maintain a relatively stable core temperature that typically ranges from 37.5 °C to 38.5 °C (99.5 °F–101.3 °F) under normal laboratory conditions. This range reflects the species’ homeothermic regulation and can be influenced by several physiological and environmental factors.
Key determinants of thermal state include:
- Ambient temperature: When the surrounding air is cooler than the thermoneutral zone (approximately 30 °C for rats), metabolic heat production increases to preserve core temperature. Conversely, exposure to temperatures above the thermoneutral range may trigger vasodilation and evaporative cooling.
- Age and developmental stage: Neonatal pups exhibit lower body temperatures (around 35 °C) due to immature thermoregulatory mechanisms, while adult rats achieve the higher adult range.
- Sex and reproductive status: Pregnant or lactating females often show a modest elevation in core temperature, linked to metabolic demands of gestation and milk production.
- Stress and activity level: Acute stressors, such as handling or exposure to novel environments, can cause transient hyperthermia through sympathetic activation. Physical activity similarly raises temperature via increased muscular work.
- Health condition: Fever associated with infection or inflammation can push core temperature above the normal ceiling, whereas hypothermia may develop during severe shock or anesthesia.
Measurement techniques commonly employed are rectal thermometry, implanted telemetry probes, and infrared thermography. Rectal probes provide quick, repeatable readings but may cause slight stress; telemetry offers continuous data without handling interference; infrared methods assess surface temperature, which correlates imperfectly with core values and requires calibration.
Understanding the precise thermal profile of rats is essential for interpreting experimental outcomes, especially in studies involving metabolism, pharmacokinetics, or neurological function, where temperature fluctuations can alter physiological responses.