How long does a mouse live in confinement? - briefly
Laboratory‑kept mice usually survive between 1.5 and 2.5 years, with the maximum lifespan rarely exceeding three years under optimal care.
How long does a mouse live in confinement? - in detail
Mice kept under controlled conditions typically live between 1.5 and 3 years. Laboratory strains such as C57BL/6, BALB/c, and Swiss outbred mice reach an average of 2 years when provided with standard rodent chow, a 12‑hour light cycle, and a temperature of 20‑26 °C. Pet mice, which often receive higher‑calorie diets and more environmental enrichment, may survive up to 3 years, though individual variation is common.
Key factors that influence longevity in captivity:
- Genetic background – Inbred strains exhibit shorter lifespans due to reduced heterozygosity, while outbred stocks tend to live longer.
- Nutrition – Balanced protein (15‑20 % of diet), adequate vitamins, and limited fat extend life expectancy; obesity shortens it.
- Housing conditions – Stable temperature, humidity (30‑70 %), and low noise reduce stress‑related mortality.
- Health monitoring – Regular screening for common pathogens (e.g., mouse hepatitis virus, Sendai virus) and prompt treatment of infections prevent premature death.
- Enrichment – Access to nesting material, tunnels, and exercise wheels lowers corticosterone levels and improves survival rates.
- Reproductive status – Breeding females experience a higher mortality risk; non‑reproductive individuals live longer.
Mortality patterns show that the majority of deaths occur after the second year, with a steep increase in age‑related diseases such as neoplasia, renal failure, and cardiomyopathy. Early‑life mortality (first 6 months) often results from congenital defects, maternal neglect, or acute infections.
Optimizing the above parameters can shift the upper lifespan limit toward 3 years, whereas neglecting any single element may reduce survival to under 1 year.