How many times per minute does a mouse's heart beat? - briefly
A typical laboratory mouse heart beats roughly 600–700 times each minute. This rate can vary with strain, age, and activity level, but averages around ten times faster than a human heart.
How many times per minute does a mouse's heart beat? - in detail
The cardiac frequency of a laboratory mouse typically ranges between 400 and 600 beats per minute. This value fluctuates according to several physiological and environmental parameters.
Young adult mice of common strains (e.g., C57BL/6, BALB/c) most often exhibit rates near 500 bpm under standard housing temperatures (20–22 °C) and resting conditions. Neonatal pups can exceed 800 bpm, while aged individuals may drop to 300–350 bpm.
Key factors influencing the pulse count include:
- Ambient temperature: Lower temperatures raise metabolic demand, pushing the heart rate upward; higher temperatures produce the opposite effect.
- Physical activity: Voluntary locomotion or handling can double the resting frequency for short periods.
- Stress and anesthesia: Acute stress elevates the rate, whereas most anesthetic agents depress it by 30–50 %.
- Genetic background: Certain knockout or transgenic lines display altered autonomic regulation, leading to measurable deviations from the baseline range.
- Sex: Male mice often show slightly higher rates than females, though the difference is modest.
Measurement techniques such as electrocardiography (ECG), telemetry implants, and high‑speed infrared plethysmography provide accurate minute‑by‑minute counts. ECG recordings in awake, freely moving mice yield values consistent with telemetry data, while anesthetized preparations typically report lower numbers due to drug effects.
For comparative context, the human resting heart rate averages 60–100 bpm, making the mouse’s cardiac rhythm roughly five to ten times faster. This rapid rate supports the mouse’s high metabolic rate and small body size, facilitating efficient oxygen delivery and waste removal across a compact circulatory system.