Maturation and spawning
performance of pond-reared Penaeus merguiensis in different
combinations of temperature, light intensity and photoperiod
Tung Hoang, S.Y. Lee, C.P. Keenan, G.E. Marsden-2002
Aquaculture
Research, 33(15):
1243-1250
Abstract:
The combined effects of temperature (23 and 27 °C),
light intensity (1100 and 2 lux or » 21.5
and 0.04 µ Einst m-2 s respectively) and photoperiod
(10 h light/14 h dark and 14 h light/10 h dark) on
ovarian maturation and spawning performance of ablated pond-reared Penaeus
merguiensis were investigated in a 51-day experiment. The results showed
that temperature was the most influential factor, followed by light
intensity, whereas the effect of photoperiod was minor. As the maturation
process progressed, the effects of temperature and light intensity became
stronger while that of photoperiod became less significant. Temperature
significantly affected all the reproductive parameters assessed. Prawns in
the 27 °C treatments outperformed those in the 23 °C treatments
(P < 0.05). The effect of light intensity was found to
have a significant effect (P < 0.05) only on the
proportion of spawners (prawns that spawned) and spawning rate. More prawns
spawned at a higher rate under dim light (2 lux) than under strong
light (1100 lux). Photoperiod affected only the proportion of prawns
reaching stage III of ovarian development (P < 0.05).
There were interactions between temperature and light intensity affecting
the proportion of prawns reaching stage III and, although not significantly,
the proportion of spawners (P = 0.177), fecundity (P = 0.134)
and survival (P = 0.061). Overall, it is recommended that a
combination of 27 °C, 2 lux and 10 h light/14 h dark is
suitable for the maturation of pond-reared P. merguiensis. There were
indications that temperature can be used to control the rate of ovarian
maturation. Also, it is possible to increase light intensity up to 1100 lux
in P. merguiensis hatcheries if prawns are ablated.
(Bribie Island Aquaculture Research Centre,
Queensland Department of Primary Industries, PO Box 2066, Bribie Island,
Queensland 4507, Australia. E-mail: Tung.Hoang@dpi.qld.gov.au
or htung_113@yahoo.com)