(A) NREM and (B) REM sleep duration in CTRL and CF male and female rats during recovery hours (16:00–21:00) after SD. Males (n = 7/control group, n = 6/CF group), females (n = 5/CTRL group, n = 5/CF group). # Difference is significant between BL and SD days (factorial repeated measures ANOVA (between subject factors: sex and treatment, within-subject factor: SD), P < 0.05). *Difference is significant between BL and SD days within same-sex, same-treatment group (one-way ANOVA, P < 0.05). CTRL: control rats. CF, cross-fostering rats; BL, baseline day; SD, sleep deprivation.