How much grain does a mouse eat per day? - briefly
A typical house mouse ingests roughly 3–5 g of grain each day, about 5–7 % of its body mass. In laboratory conditions the range can vary from 2 to 6 g depending on age and diet composition.
How much grain does a mouse eat per day? - in detail
A typical adult house mouse (≈20 g body mass) consumes roughly 0.5–1 g of dry grain each day. This quantity represents about 2.5–5 % of its body weight in dry matter, a range consistently reported in laboratory feeding trials.
Factors that modify daily grain intake include:
- Body weight: larger individuals require more absolute food but maintain a similar percentage of body mass.
- Ambient temperature: colder environments increase metabolic demand, raising consumption by up to 30 %.
- Activity level: mice engaged in extensive locomotion or nesting behavior eat more than sedentary counterparts.
- Grain composition: high‑energy seeds (e.g., wheat, corn) are eaten in smaller volumes than low‑energy cereals (e.g., rice, barley).
- Feeding regime: ad libitum access yields the upper end of the range; restricted schedules reduce intake proportionally.
Experimental data illustrate the relationship between weight and intake. In a controlled study, mice weighing 18 g averaged 0.45 g of wheat kernels per day, while 22 g individuals consumed 0.55 g. When the ambient temperature was lowered from 22 °C to 15 °C, the same 20 g mice increased consumption from 0.60 g to 0.78 g, confirming the thermoregulatory effect.
Nutritional conversion shows that 0.8 g of dry grain provides approximately 3 kcal, satisfying roughly 15 % of the mouse’s basal metabolic requirement (≈20 kcal day⁻¹). Protein content (≈12 % of grain dry weight) delivers about 0.1 g of protein daily, a fraction of the 2–3 g protein needed for tissue maintenance and growth.
Seasonal and environmental variations can shift the intake window. Wild mice in temperate regions increase grain consumption during winter months, reaching up to 1.2 g per day, whereas summer diets supplemented with insects and fruits may reduce grain reliance to 0.4 g.
For laboratory or pet care protocols, providing 0.6–0.9 g of standard rodent chow per mouse per day ensures adequate energy and nutrient supply while avoiding excess that could lead to obesity. Precise measurement using analytical balances is recommended to maintain consistent dietary conditions across experimental groups.