Meeting Abstract
P3.67 Jan. 6 Metabolic cost and power requirements of maximal labriform swimming in bluegill sunfish (Lepomis macrochirus). JONES, E.A.*; LUCEY, K.S.; ELLERBY, D.J.; Wellesley College; Wellesley College; Wellesley College dellerby@wellesley.edu
At low swimming speeds bluegill sunfish swim in the labriform mode, generating lift and thrust by beating their pectoral fins. We measured the fin kinematics and energy costs of maximal labriform swimming in bluegill swimming in a recirculating flume at 22 ºC. The maximum speed sustained by labriform swimming was 1.22 � 0.08 body lengths/s (N = 6). At speeds greater than this, myotomal muscle was recruited to supply additional power by beating the caudal fin. Just before the gait transition the pectoral fins beat at a frequency of 2.8 � 0.2 Hz (N = 6). The resting rate of oxygen consumption of bluegill was 67.4 � 7.4 mg O2 kg-1 h-1 (N = 6). The rate of oxygen consumption during maximal labriform swimming was 138.3 � 13 mg O2 kg-1 h-1 (N = 6). Subtracting resting from total metabolism, approximately 70.9 � 10.7 mg O2 kg-1 h-1 (N = 6) was used to power swimming. The power available from the main pectoral adductor and abductor muscles at 2.8 Hz was measured using the work loop technique. The mass specific power output of the adductor profundus and abductor superficialis muscles were not significantly different. The mean power output, pooled for both muscles was 14.9 � 2.4 W kg-1 (N = 11). All data are shown as mean � SEM.
