How many pups are in a domestic mouse litter? - briefly
A typical house mouse litter consists of five to ten offspring, with an average of six to eight pups.
How many pups are in a domestic mouse litter? - in detail
Domestic mice typically produce litters ranging from three to fourteen offspring, with the most common size falling between five and seven pups. This variation reflects genetic strain differences, maternal age, and environmental conditions.
- Laboratory strains such as C57BL/6 often average six to eight young per litter.
- Outbred or pet mice may show broader ranges, occasionally reaching up to twelve or more.
- Young dams (first parity) usually have smaller litters, while experienced females tend to produce larger ones, up to the upper limit of the species.
Nutrition directly influences litter size. Adequate protein (18‑20 % of diet) and caloric intake increase both the number of embryos and their survival rate. Conversely, caloric restriction or nutrient deficiencies can reduce litter size by 20‑30 %.
Seasonal photoperiod affects reproductive output. Longer daylight periods stimulate estrous cycles, often resulting in larger litters compared to short‑day conditions.
Gestation lasts approximately 19‑21 days. Litter size does not significantly alter gestation length, but larger broods may increase the risk of intra‑uterine competition, leading to slightly lower birth weights.
Post‑natal mortality averages 5‑10 % under optimal husbandry; overcrowding, poor ventilation, or inadequate nesting material can raise this figure substantially. Providing at least 0.5 sq ft of nesting substrate per pup and maintaining ambient temperature around 22 °C reduce mortality.
In summary, a typical domestic mouse delivers five to seven pups per birth, with extremes of three to fourteen depending on strain, maternal experience, diet, and environmental factors. Proper nutrition, lighting, and housing conditions maximize both litter size and pup survival.