How many offspring can a mouse have at one time? - briefly
A mouse usually gives birth to a litter of 5–12 young, averaging around seven pups per delivery. The exact number varies with species, age, and environmental conditions.
How many offspring can a mouse have at one time? - in detail
Mice generally produce litters ranging from three to twelve pups, with the most common size falling between five and eight. Laboratory strains such as C57BL/6 often average six to seven offspring per birth, while outbred or wild‑type populations can reach the upper limit of twelve under optimal conditions.
Factors influencing litter size include:
- Genetic background: inbred lines tend to have more consistent, slightly smaller litters; outbred stocks display greater variability.
- Maternal age: young females (8–12 weeks) achieve peak productivity; very young or aged females produce fewer pups.
- Nutrition: diets rich in protein and energy increase both litter size and pup viability.
- Environmental stressors: high density, temperature extremes, or disease reduce the number of offspring.
The gestation period for a mouse lasts approximately 19–21 days. A single female can undergo multiple reproductive cycles annually, potentially yielding dozens of offspring within a year. Recorded maximum litter sizes reach fifteen pups, but such cases are rare and typically result from exceptional genetic or environmental circumstances.