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Fig. 2. Mean venous blood oxygen partial pressure (PVO2)
measurements in the ductus Cuvier for cold-acclimated and warm-acclimated
rainbow trout during graded exercise. Values were derived from periods of
steady-state swimming at each velocity increment. To permit comparisons
between the cold- and warm-acclimated fish, swimming velocity is expressed as
a percentage of the critical swimming speed (%Ucrit).
Horizontal and vertical bars indicate the S.E.M. Dissimilar letters represent
statistical difference within a swim. Values without letters were not included
in the repeated-measures analysis of variance (ANOVA). Asterisks represent
significant difference between the acclimation temperatures at similar
%Ucrit. The inset presents the data for the first
(habituation) swim. 1 torr=133.3 Pa.