Meeting Abstract
P1.41 Jan. 4 Parental swimming performance influences the ontogeny of cardiac and metabolic performance in larval zebrafish (Danio rerio) GORE, MR*; BURGGREN, WW; Univ. of North Texas; Univ. of North Texas mrg0107@unt.edu
Superior swimming performance in adult fish is likely passed on to their offspring, but the ontogeny of the appearance of superior performance and the requisite enhanced cardio-respiratory support for locomotion has not been determined. Is expression of the suite of parental traits enabling superior swimming performance in their offspring dependent upon their achieving juvenile/adult morphology, or does it appear earlier in larvae? To answer this, adults were classified into three groups based on swimming performance stamina, followed by measurement of length, mass, and width. Larval offspring from the two parental groups -high stamina parents (HSP) and low stamina parents (LSP)- were reared at 27°C in aerated water (21% O2). Routine heart rate (fH,r) and routine mass specific oxygen consumption (MO2,r) were recorded through 21dpf. The fH,r at 2dpf of LSP larvae was 164 � 1 b�min-1, compared to a much lower level of 125 � 2 b�min-1 for HSP larvae. fH subsequently peaked at 203 � 1 b�min-1 at 5dpf in the HSP group, compared to 207 � 1 b�min-1, at 4dpf in the LSP larvae. These significant (P < 0.05) differences persisted through 21dpf. The MO2,r at 2dpf of HSP larvae was 0.09 umol�mg-1�hr-1, compared to 0.03 umol�mg-1�hr-1 in LSP larvae. MO2,r subsequently peaked at 0.70 umol�mg-1�hr-1 at 9dpf in the HSP larvae, compared to 0.71 umol�mg-1�hr-1, at 9dpf in the LSP larvae. These values dramatically decreased before leveling off at around 0.20 umol�mg-1�hr-1 and 0.15 umol�mg-1�h-1, respectively. The early appearance of differences in cardiovascular and aerobic fitness in early larvae derived from adults with different levels of swimming performance shows that differences in resting cardiovascular and aerobic performance in larvae do not require attainment of adult/juvenile body features.
