The Israeli Journal of Aquaculture - Bamidgeh 55(4), 2003
The 7th Annual Dan Popper Symposium
PARENTAL INFLUENCE ON SEX RATIOS IN PROGENY OF THE
EUROPEAN SEA BASS (DICENTRARCHUS LABRAX )
S. Gorshkov*, I. Meiri, H. Rosenfeld, S. Ben-Atia, S. Lutzki, A. Peduel, B. Ron, G. Gorshkova, A. Skvortzov and A. Tandler
Israel Oceanographic and Limnological Research, National Center for Mariculture,
PO Box 1212, Eilat, 88112, Israel
Females of the European sea bass (Dicentrarchus labrax) grow 20-50% faster than males.
Therefore, they are more in demand for commercial farming. This fact generated much interest
in developing female monosex populations. The majority of recent studies focused on the influence
of temperature on sex determination in sea bass. However, information on parental influences
on the sex ratio is still limited and has been only partially documented. The present experiments
aimed at studying the parental effects on sex ratios of the progeny in sea bass. The study
was principally based on analyzing progeny of four families produced in a diallel crossing experiment
(2 x 2 type or complete bi-factorial mating design), reflecting both the maternal and paternal
genetic relatedness among progeny.
The proportion of females varied significantly (p <0.05) among families (20.7-68.2%). There
were significant maternal and paternal effects on the proportion of females within the progeny.
The effect of parental interactions on the sex ratio of the progeny was also significant. Parents
had a significant effect (p <0.05) on total length and body weight in the progeny.
In addition to temperature manipulations proposed in our earlier studies, an improved female
to male ratio of sea bass will probably be attained by directional selection of parents that produce
the highest proportion of female progeny. Future use of DNA markers for both parents and
progeny produced by mass spawning may substantially facilitate this selection.