How do you wean newborn mice?

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How do you wean newborn mice? - briefly
«Introduce a nutritionally balanced powdered diet, moistened with water or milk replacer, at about three weeks of age, and gradually increase its proportion while limiting the dam’s milk access.»
«Complete weaning is achieved when the pups consistently consume solid feed exclusively for several consecutive days.»

How do you wean newborn mice? - in detail
Weaning of neonatal mice begins around post‑natal day 21, when pups are physiologically capable of digesting solid nutrients. Prior to this point, dam’s milk provides all required calories and antibodies; abrupt removal before the appropriate age results in high mortality.
Preparation of the environment includes:

Clean, well‑ventilated cage with soft bedding to prevent injuries.
Access to a high‑protein rodent chow formulated for weanlings, typically containing 20 % protein and 5 % fat.
Fresh water bottles positioned at a height reachable by the young animals.

The transition proceeds in stages:

Place solid food in the cage on the floor or in a shallow dish to encourage exploration.
Reduce dam’s time with the litter by limiting nursing sessions to 2–3 hours per day, thereby stimulating self‑feeding.
Increase the proportion of solid food daily while monitoring consumption; by day 28, pups should rely exclusively on chow and water.

Health monitoring focuses on weight gain of at least 2 g per week and normal activity levels. Any decline in body weight or signs of dehydration require immediate intervention, such as supplemental formula administered via a fine‑gauge pipette.
Common issues include:

Insufficient access to food, leading to prolonged dependence on maternal milk.
Overcrowding in the cage, which can cause competition and reduced intake.
Introduction of adult chow too early; excessive fiber or low caloric density impedes growth.

Successful weaning results in independent, healthy juveniles ready for experimental use or further development. Continuous observation and gradual dietary adjustment remain essential for optimal outcomes.