How much water do mice drink? - briefly
Adult laboratory mice usually ingest 4–7 ml of water each day, with intake varying by diet, ambient temperature, and strain. Younger or pregnant individuals may drink up to 10 ml daily.
How much water do mice drink? - in detail
Mice typically consume between 4 ml and 7 ml of water each day. The exact amount varies with body mass; a 20‑gram mouse drinks roughly 4 ml, while a 30‑gram individual may reach 6 ml. This relationship can be expressed as 0.2 ml to 0.25 ml of water per gram of body weight per 24 hours.
Several variables modify intake:
- Age: Juvenile mice ingest less water than adults because their diet contains higher moisture from milk or soft chow.
- Strain: Genetic background influences metabolism; for example, C57BL/6 mice average 5 ml/day, whereas BALB/c mice may approach 6 ml.
- Ambient temperature: Temperatures above 25 °C increase respiration and evaporative loss, raising consumption by up to 30 %.
- Humidity: Low relative humidity (<30 %) similarly elevates drinking volume to compensate for greater evaporative dehydration.
- Dietary composition: High‑protein or high‑salt feeds elevate fluid requirements; dry pelleted diets can double intake compared with moisture‑rich gel diets.
Experimental measurements frequently use graduated capillary tubes or calibrated water bottles, recording daily consumption over a 7‑day baseline. Data pooled from multiple laboratories report a mean of 5.3 ml/day (standard deviation ≈ 0.8 ml) for adult laboratory mice housed under standard conditions (22 °C, 50 % humidity, ad libitum chow).
When calculating water needs for a colony, multiply the average daily intake per mouse by the number of animals and by the number of days in the experimental period. Adjust the figure upward if any of the factors above are present. This approach ensures adequate hydration, prevents confounding variables in physiological studies, and maintains animal welfare standards.