How many babies do mice have? - briefly
«Mice usually produce litters containing five to ten young, averaging roughly six to eight offspring per birth.» «Litter size can fluctuate according to species, nutrition, and environmental factors.»
How many babies do mice have? - in detail
Mice typically produce litters ranging from three to twelve offspring, with an average of five to six pups per reproductive event. The exact number depends on several biological and environmental variables.
Key determinants of litter size include:
- Species: The common house mouse (Mus musculus) often yields five to six young, while larger species such as the deer mouse (Peromyscus maniculatus) can reach eight to ten.
- Age of the dam: Young females (first estrous cycle) tend to have smaller litters; reproductive performance improves after the second or third parity.
- Nutritional status: Adequate protein and calorie intake correlates with higher pup counts; caloric restriction reduces litter size.
- Seasonal factors: In temperate regions, breeding peaks in spring and summer, periods associated with larger litters due to favorable conditions.
- Genetic lineage: Selective breeding for laboratory strains (e.g., C57BL/6) standardizes litter sizes around five to six, whereas wild populations display broader variation.
Gestation lasts approximately nineteen to twenty‑one days, after which the dam gives birth to altricial pups that gain weight rapidly, reaching weaning weight by three weeks. High reproductive capacity enables mouse populations to expand quickly under suitable circumstances.