Oxygen consumption of germfree and conventional mice

Oxygen consumption was determined in germfree and conventional mice using a respirometer which enabled us to make precise corrections for variations in temperature or barometric pressure. In 20, 3-minute observations on 21 germfree and 21 conventional mice, the germfree animals consumed an average of 2.11 ml of oxygen per gram body weight per hour in comparison to 2.37 ml for the conventional mice. This difference was not accompanied by a difference in rectal temperature.