Mean (±SEM) number of distress calls following an initial separation from the dam/litter in Con-F1 (n = 14–16/day), Sal-F1 (n = 14–18/day), and Mor-F1 (n = 14–18/day) animals at PND3, 6, 9, and 12. One male and one female per litter were examined on each postnatal day and no animals were tested twice (data are collapsed across sex). The number of calls increased across postnatal days; *p < .05 as compared to PND3 and PND12, **p < .05 when compared to all other days. There was a main effect of maternal condition with both Sal-F1 and Mor-F1 producing fewer calls (p < .001).