(A) Vigilance state distribution through light-dark period and (B) number of REM sleep onsets in CTRL and CF male and female rats during BL day. Males (n = 7/control group, n = 6/CF group), females (n = 5/CTRL group, n = 5/CF group). # Difference is significant between CTRL and CF rats (factorial ANOVA (factors: sex and treatment), P < 0.05). *Difference is significant between CTRL and CF rats within same-sex group (one-way ANOVA, P < 0.05). CTRL, control rats; CF, cross-fostering rats; BL, baseline day.