title: Sources of variation in oxygen consumption of aquatic animals demonstrated by simulated constant oxygen consumption and respirometers of different sizes.
abstract: As intermittent-flow respirometry has become a common method for the determination of resting metabolism or standard metabolic rate (SMR), this study investigated how much of the variability seen in the experiments was due to measurement error. Experiments simulated different constant oxygen consumption rates (M˙O2 ) of a fish, by continuously injecting anoxic water into a respirometer, altering the injection rate to correct for the washout error. The effect of respirometer-to-fish volume ratio (RFR) on SMR measurement and variability was also investigated, using the simulated constant M˙O2 and the M˙O2 of seven roach Rutilus rutilus in respirometers of two different sizes. The results show that higher RFR increases measurement variability but does not change the mean SMR established using a double Gaussian fit. Further, the study demonstrates that the variation observed when determining oxygen consumption rates of fishes in systems with reasonable RFRs mainly comes from the animal, not from the measuring equipment.
authors.affiliation: Marine Biological Section, Department of Biology, University of Copenhagen, Strandpromenaden 5, DK-3000 Helsingør, Denmark.
authors.forename: M B S
authors.initials: MB
authors.lastname: Svendsen
authors.affiliation: Department of Biological Sciences, Indiana University South Bend, South Bend, IN 46634, U.S.A.
authors.forename: P G
authors.initials: PG
authors.lastname: Bushnell
authors.affiliation: Marine Biological Section, Department of Biology, University of Copenhagen, Strandpromenaden 5, DK-3000 Helsingør, Denmark.
authors.forename: E A F
authors.initials: EA
authors.lastname: Christensen
authors.affiliation: Marine Biological Section, Department of Biology, University of Copenhagen, Strandpromenaden 5, DK-3000 Helsingør, Denmark.
authors.forename: J F
authors.initials: JF
authors.lastname: Steffensen
mesh_terms: D000818:Animals; D001481:Basal Metabolism; D003530:Cyprinidae / Q000502:physiology*; D004734:Energy Metabolism; D010100:Oxygen / Q000378:metabolism; D010101:Oxygen Consumption
chemical_list: D010100:Oxygen
keywords: aquatic respirometry; intermittent-flow respirometry; measurement error