Overview and Meaning

Mice are a altricial species. During the first few weeks of life they rely on their mother's milk as a source of food and as a way to learn about the food eaten by their mother. The amount of milk received can affect a pup's adult weight and aggressiveness. Therefore, weaning weight of male pups can have long term effects on their ability to become dominant adults (Latham & Mason, 2004).

A dam will spend the bulk of her time in the nest on top of her pups to keep them warm and to allow them to nurse at her teats.

Description

The dam is over the pups, relatively immobile, bilaterally symmetric, with the head not depressed and in a low dorsal arch posture supported by rigid fore- or hind-limbs. Pups are attached to the nipples.  

(Coutellier, et. al. 2008)