Heritability of Swimbladder Inflation in Striped Bass
R.M.
Harrell, W. Van Heukelem, J.M. Jacobs, J.R. Schutz, J.U. Takacs, D.
Jacobs-2002
North
American Journal of Aquaculture, 64(2): 117–121
Abstract:
Lack
of swim bladder (gas bladder) inflation can be a serious problem in the
culture of striped bass Morone saxatilis, resulting in high mortalities and
skeletal anomalies. We undertook a heritability study to examine the genetic
basis for this trait. A 7 × 10 (female × male) factorial mating study
resulted in 70 full-sibling families. Each full-sibling family was reared
individually for 10 d posthatch, and sampled surviving larvae were
microscopically examined for swim bladder inflation. Full-sibling and dam
half-sibling heritability estimates were 0.35 and 0.04, respectively. Low
half-sibling heritabilities indicate that there is little additive genetic
variance that can be exploited for selection purposes. The higher
full-sibling estimates suggest swim bladder inflation is predominantly
influenced by dominance, epistatis, or environmental factors.
(University
of Maryland Center for Environmental Science, Horn Point Laboratory,
Cambridge, Maryland 21613, USA)