Table 1.

Body composition and indirect calorimetry data for 5-mo-old male wild-type and Ostα^−/− mice

	Wild-Type	Ostα−/−
Body weight, g	28.2 ± 0.5	27.3 ± 0.5
Body fat, %	13.4 ± 1.0	8.9 ± 0.7*
Lean mass, %	69.8 ± 0.9	73.6 ± 0.5*
	24-h cycle
V̇o2, ml·kg−1·h−1	4,738 ± 132	5,120 ± 186
V̇co2, ml·kg−1·h−1	4,367 ± 115	4,804 ± 170
Respiratory quotient (V̇co2/V̇o2)	0.915 ± 0.003	0.933 ± 0.005*
Energy expenditure, kcal·kg−1·h−1	23.5 ± 0.7	25.4 ± 0.9
Calories consumed, kcal·kg−1·h−1	18.8 ± 0.9	21.1 ± 0.9
Water consumed, ml·kg−1·h−1	0.93 ± 0.05	1.20 ± 0.07*
Activity, counts/h	173 ± 31	130 ± 16
	12-h light cycle
V̇o2, ml·kg−1·h−1	4,365 ± 149	4,781 ± 193
V̇co2, ml·kg−1·h−1	3,838 ± 118	4,293 ± 160*
Respiratory quotient (V̇co2/V̇o2)	0.876 ± 0.005	0.896 ± 0.005*
Energy expenditure, kcal·kg−1·h−1	21.4 ± 0.7	23.5 ± 1.0
Calories consumed, kcal·kg−1·h−1	11.8 ± 1.0	13.4 ± 0.6
Water consumed, ml·kg−1·h−1	0.50 ± 0.04	0.72 ± 0.08*
Activity, counts/h	86 ± 19	67 ± 10
	12-h dark cycle
V̇o2, ml·kg−1·h−1	5,252 ± 135	5,587 ± 180
V̇co2, ml·kg−1·h−1	5,095 ± 142	5,507 ± 188
Respiratory quotient (V̇co2/V̇o2)	0.969 ± 0.004	0.984 ± 0.008
Energy expenditure, kcal·kg−1·h−1	26.3 ± 0.7	28.0 ± 0.9
Calories consumed, kcal·kg−1·h−1	28.6 ± 1.5	31.6 ± 1.9
Water consumed, ml·kg−1·h−1	1.53 ± 0.09	1.85 ± 0.08*
Activity, counts/h	291 ± 51	217 ± 31

Values are means ± SE (n = 6–7). V̇o₂, O₂ uptake; V̇co2, CO₂ output.

^*P < 0.05 vs. wild-type.