**Figure 4.** **Mild hypothyroid Pax8 +/- mice exhibit reduced basal metabolic rate and compromised physical performance.** (**A**) Basal daily energy intake per day at 10-12 months of life. n = 5 Wt, n = 4 Pax8 +/- (the n reflects the number of cages). (**B**) Fasting-induced energy intake at 10-12 months of life. n = 21 Wt, n = 14 Pax8 +/-. (**C**) Lipid content in faeces. n = 7 Wt, n = 6 Pax8 +/-. (**D**) Body temperature. n = 12 Wt, n = 8 Pax8 +/-. (**E**) Determination of RER in metabolic cages. n = 8 Wt, n = 7 Pax8 +/-. (**F**) Determination of heat production in metabolic cages. n = 8 Wt, n = 7 Pax8 +/-. (**G**) Determination of spontaneous locomotor activity (y + x axis) in metabolic cages. n = 8 Wt, n = 7 Pax8 +/-. (**F**) Determination of run distance in metabolic cages. n = 8 Wt, n = 7 Pax8 +/-. (**H**) Triglyceride concentration in plasma. n = 18 Wt, n = 13 Pax8 +/-. (**I**) Total cholesterol, HDL and LDL/VLDL levels in serum. n = 7 per group. (**J**) Blood levels of Gpt. n = 7 per group. (**K**) Blood levels of Got. n = 7 per group. (**L**) Time to fall from an accelerating rotarod at 7-10 months of life. n = 27 Wt, n = 20 Pax8 +/-. (**M**) Time to fall in wire hang test at 7-10 months of life. n = 27 Wt, n = 20 Pax8 +/-. Data are represented as the mean ± SEM. Unless otherwise stated, mice were 7-month old at the time of experimentation. * p-value < 0.05. T-test two tailed.