adult stage true mouse_developmental_stage MmusDv:0000040 This term was obsoleted to include the mature stage into the ontology. Both terms have the same children, but contains of children (children of children) differ. The organisation of the postnatal development time in mouse is debatable, literature usually refers to mature or immature mice, with milestone around 6-8 weeks post-natal. Mouse developmental stage that refers to a mouse which is over 5 weeks old. mature mature stage