Temporal parameters of responsiveness to maternal pheromone in Acomys cahirinus

In a series of two-choice preference tests, 15-and 20-day-old A. cahirinus pups were found to prefer chemical cues produced by a lactating female over such cues emanating from a nonlactating female. Twenty-five-day-old pups, however, showed reliable preferences for bedding material soiled by a nonlactating female when paired against either lactating female-soiled bedding or clean bedding material. Although 25-day-old pups are no longer responsive to chemical stimuli produced by lactating females (maternal pheromone), 2-day-old pups are attracted to such cues emanating from lactating females as late as 35 and 38 days postpartum. Therefore, there does not appear to be close temporal synchrony between the waning of responsiveness to maternal pheromone and the production thereof.