Observations on
growth, sexual maturity and spawning performance of pond-reared Penaeus
merguiensis
T. Hoang, S.Y. Lee, C.P. Keenan,
G.E. Marsden-2002
Aquaculture
Research, 33(11):863-874
Abstract:
This 12-month preliminary study
investigated the development of sexual characters, primary sexual maturity,
ovarian maturity and spawning performance of pond-reared Penaeus
merguiensis in relation to culture conditions in south-east Queensland,
Australia. Post-larvae of P. merguiensis were produced and cultured
in two 60-m3 tanks during the first 14weeks. Before winter, they
were harvested and stocked in three different overwintering facilities: a
200-m2 covered pond, two 60-m3 outdoor tanks and a
15-m3 indoor, recirculated tank at a stocking density of 10
individuals m-2. The development of sexual characters was found
to be similar to that reported previously in wild P. merguiensis.
Males matured at younger ages and smaller sizes than females. Overall, the
average size at primary sexual maturity of pond-reared P. merguiensis
was 23.1mm carapace length for males (possessed spermatophores) and 29.3mm
for females (being impregnated). Water temperature and the availability of
natural food strongly influenced prawn growth, maturity rate and their
subsequent spawning performance. Growth, maturity rate and spawning
performance of prawns in the covered pond were significantly higher than in
the other overwintering facilities. Prawns started mating at 6-7months,
reached full ovarian maturation and spawned as early as about 8 (peaked at
9-11)months from hatching, producing high fecundity and viable larvae. There
was a strong relationship (P<0.001) between prawn size and
fecundity. The results of this study suggest a potential for using
pond-reared broodstock P. merguiensis for hatchery production and for
domestication or selective breeding programmes.