Which age range is typical for weaning in mice?

• A. 14-21 days
• B. 21-28 days
• C. 28-35 days
• D. 35-42 days

Answer: (B)

Weaning in mice occurs when pups are developmentally ready to leave maternal milk and eat solid food on their own. In most laboratory settings, this readiness falls within a three-week period after birth, so the typical weaning window is 21 to 28 days. Waiting until about day 21–28 balances the pups’ growth and nutritional needs with the dam’s ability to nurse and care for the litter, making it the standard practice.

Wean earlier, around 14–21 days, before pups are consistently ready to sustain themselves on solid food can risk poor nutrition and higher mortality. Wean later, after 28 days, is less common and can complicate housing and social dynamics. Therefore, 21–28 days is the best answer.