Journal of Applied Physiology, Vol 57, Issue 5 1591-1593, Copyright © 1984 by American Physiological Society
A low-cost modular oxygen-consumption device for small animals
P. A. Arundel, B. R. Holloway and P. M. Mellor
This paper describes a simple apparatus enabling the O2 consumption of
small animals to be monitored. The system consists of a sensitive
solid-state pressure transducer linked via a relay to a small peristaltic
pump. While the animal breathes air in its closed chamber the CO2 expired
is removed by an absorber; hence the pressure falls. The signal is sensed
by the transducer triggering the pump to deliver a set volume of O2 to the
chamber. The number of pump operations per unit time necessary to keep the
system equilibrated is a measure of the O2 consumption rate. Each device is
built as a module, up to four being mounted in one assembly controlled by a
microcomputer. A balance control, priming switch, pump-volume setting, and
electromagnetic counter are built into each front panel. Calibration is
achieved be removing a known volume of air from the system with no animal
present and counting the number of operations to return the chamber to
equilibrium.
