Placement of bioimpedance spectroscopy electrodes on a mouse.

<p>Four 25G needles are placed subcutaneously along the midline of the back and serve to connect the electrodes to the animal. The B electrode (blue) is placed at the intersection between the median line and the line between the ears. The A electrode (black) is placed 1 cm from B towards the muzzle. The C electrode (yellow) is placed between the median line and that joining the thigh muscles. The D electrode (red) is placed 1 cm backwards at the base of the tail. The length between B and C needle electrodes is measured; this parameter, as well as the age and weight of the animal, is required by the software to calculate the proportion of fat mass.