title: A high-precision automatic closed-circuit respirometer for small animals.
abstract: An automatic apparatus for the continuous measurement of O2 consumption of small laboratory animals is described. By use of a high-sensitivity pressure transducer with associated circuitry together with a peristaltic O2 delivery system, the closed respirometer chamber is maintained at atmospheric pressure +/- 0.5 mmH2O. O2 delivery is measured to within 0.25 ml by recording rotations of the peristaltic pump, following calibration by the withdrawal of a preset volume of air from the chamber. Static trials (with the chamber empty) indicate a high degree of reproducibility of data with the chamber pressure remaining at atmospheric pressure +/- 0.5 mmH2O as a result of the proportional, as opposed to fixed-volume, delivery of O2. Trials with mice and rats have likewise produced data with a high degree of reproducibility.
mesh_terms: D000818:Animals; D000830:Animals, Laboratory; D001273:Atmosphere Exposure Chambers; D002138:Calibration; D012129:Respiratory Function Tests / Q000295:instrumentation*; D014160:Transducers, Pressure