What does a newborn mouse eat? - briefly
Newborn mouse pups are fed exclusively on their mother’s milk, which provides all essential nutrients for the first three weeks of life. Following weaning they begin consuming solid foods such as grains, seeds, and insects.
What does a newborn mouse eat? - in detail
A newborn mouse relies exclusively on its mother’s milk for nourishment. The lactation period lasts approximately three weeks, during which the pup receives a nutrient‑dense secretion produced by the dam’s mammary glands. Milk composition includes high concentrations of proteins (mainly casein and whey), essential amino acids, lipids rich in long‑chain fatty acids, lactose as the primary carbohydrate, and a suite of vitamins (A, D, E, K) and minerals (calcium, phosphorus, magnesium). Immunoglobulins transferred in the colostrum provide passive immunity until the offspring’s own immune system matures.
Feeding behavior is continuous; pups nurse every 1–2 hours, stimulating milk flow through vigorous suckling. The mother’s milk supply adjusts dynamically to the litter size, ensuring that each individual receives sufficient calories—roughly 4 kcal per gram of body weight per day during the first week, decreasing slightly as growth progresses.
If the dam is unavailable, artificial formulas designed for laboratory rodents can substitute. Such formulas mimic natural milk by containing:
- 20–25 % protein (casein‑based)
- 10–12 % fat (vegetable oil blend)
- 30–35 % lactose
- Balanced mineral and vitamin mix
- Added nucleotides and prebiotic oligosaccharides
These substitutes must be warmed to body temperature (≈37 °C) and delivered via a small syringe or specialized feeding tube, with volumes of 0.1–0.2 ml per feeding, adjusted for the pup’s weight and age.
Around day 14, the dam begins introducing solid food particles into the nest. Pups start nibbling on the dam’s chow, which contains grains, protein sources, and fiber. This gradual transition, known as weaning, typically completes by day 21, after which the young mouse fully depends on solid diet. The weaning diet provides:
- 18–20 % protein
- 4–5 % fat
- 5–6 % fiber
- Adequate levels of vitamins B, C, and E
- Minerals such as calcium, phosphorus, and trace elements
In summary, the early nutrition of a neonatal mouse consists of exclusive maternal milk rich in macronutrients, immunological factors, and micronutrients, followed by a staged introduction of solid rodent chow that supports continued growth and physiological development.