Fig. 4.

Physiological mechanism for enhanced weight gain in XX compared to XY mice. Four Core Genotypes mice were analyzed for energy balance using indirect calorimetry, activity monitoring (horizontal and vertical planes), and food intake monitoring [24,25]. Results revealed that the primary difference in energy balance between XX and XY mice irrespective of original gonadal type was increased food intake in XX mice during the light phase of the circadian cycle. XX mice also had higher respiratory quotient (RQ) during the light phase, likely reflecting their food intake. Data summarized from [24,25].