How long can a mouse survive without food? - briefly
A mouse typically endures roughly two to four days without nourishment, with survival time influenced by temperature, age, and health status.
How long can a mouse survive without food? - in detail
A mouse can endure several days without ingesting calories, but the exact period depends on age, strain, ambient temperature, and hydration status. Laboratory data indicate that an adult laboratory mouse typically reaches a lethal point after 5–7 days of total food deprivation when water remains available. Younger pups, whose glycogen stores are limited, may succumb within 2–3 days. Conversely, adult mice kept at lower temperatures expend more energy for thermoregulation and may die sooner, whereas those housed at thermoneutral conditions can survive toward the upper end of the range.
Key physiological factors influencing survival:
- Metabolic rate: Small mammals have high basal metabolic rates; a mouse consumes roughly 3–4 kcal g⁻¹ day⁻¹, rapidly depleting energy reserves.
- Body composition: Fat stores provide a short‑term buffer; leaner individuals possess less reserve and deteriorate faster.
- Thermoregulation: Exposure to cold accelerates lipid and carbohydrate utilization, shortening the viable period.
- Hydration: Access to water prolongs life markedly; without both food and water, mortality occurs within 24–48 hours.
Experimental observations:
- Standard chow withdrawal: Adult C57BL/6J mice survived 5.5 days on average before reaching a humane endpoint.
- Fasting at 22 °C vs. 30 °C: Mice at 22 °C died after ~5 days, whereas those at 30 °C survived up to 7 days, reflecting reduced thermogenic demand.
- Neonatal pups (7 days old): Mortality observed after 2 days of complete nutrient deprivation.
In summary, a typical adult mouse can persist without solid food for roughly half a week, provided water is supplied and environmental conditions are favorable. Variations in strain, developmental stage, and temperature can shift this window by one to two days in either direction.