Step Procedure accomplished Age (wks) Equipment/Reagent Data Collected 1 Mice are group housed and quarantined according to sex and strain 6-8 - - 2 All mice are singly housed and given access to a running wheel (acclimation period) 8-9 mouse cage with running wheel - 3 Wheel running activity is monitored and collected for either 7 or 21 consecutive days 9-15 mouse cage with running wheel, computer wheel running activity 4 Body weights (to the nearest 0.1 g) are collected weekly throughout the study 9-15 top-loading balance scale body weights
• Solid-surface running wheel (450 mm in circumference (C), 143 mm in diameter (D), and 35 mm wide (W))
• Computerized odometer: Sigma Sport BC500 and BC600 (Olney, IL), bicycle accessory adapted for the mouse solid-surface running wheel.
• Top-loading balance scale
• Cleaning supplies
a. To eliminate the possibility of the mice "coasting" on the mesh wheels and resulting in an overestimation of daily activity levels, solid-surface wheel are used (see above).
b. At 8 wk of age each mouse is acclimated with a solid-surface running wheel, interfaced with a computer/odometer, for at least a week.
c. Each mouse is then weighed weekly throughout the testing period (4.55 g bw is required to achieve a quarter turn in the running wheel).
d. Beginning at about 63 days of age (9 wk), distance run (km) and duration (min) are noted every 24 h, and average speed of activity (m/min) is calculated. The onset of data collection may vary depending on the availability of the mice.
e. To overcome the effects of acute fluctuations in activity due to sex hormones or temperature variations in the Vivarium, phenotypic data are reported as means across the monitoring period.
f. Wheel running activity is monitored and collected for either 7 or 21 consecutive days.
Running wheel activity: daily distance, daily duration, and speed.
Body weight: weekly