The effect of
light intensity on development and hatching success of lingcod, Ophiodon
elongatus (Girard), eggs
M.A. Cook, M.B. Rust-2002
Aquaculture
Research, 33(3):
217222
Abstract:
The influence of incubation light
intensity on development and hatching success of the lingcod (Ophiodon
elongatus Girard) was studied by determining time to hatch, per cent
hatch (total and viable) and per cent of deformities for embryos incubated
at three different light intensities: ~0, 1, and 563 lux. Photoperiod for
the last two treatments was 16 h dark: 8 h light. Chemical parameters throughout incubation remained within acceptable
ranges. Hatching in all treatments began 43 days post fertilization (353 °C
days) and was complete on day 46 (377 °C days),
with peak hatch for all treatments on day 44 (361°C days). Per cent viable hatch for eggs incubated in the 1 lux treatment
(88.6 +/- 2.1%; mean +/- SEM)
was significantly greater than eggs incubated in the
0
lux (59.6 +/- 11.3%)
and 563 lux (61.4 +/- 9.2%)
treatments. A significantly greater per cent of deformed embryos with curled
bodies occurred at 563 lux (9.5 +/- 2.6%)
compared with the 1-lux treatment (2.5 +/- 0.6%).
No significant differences for the other categories of deformities (ball,
short, distended gut) were detected among treatments. Total deformities (all
categories combined) for
0
lux (16.0
+/- 4.2%) and 563 lux (17.2 +/- 3.3%)
were significantly greater than total deformities for 1 lux (5.0 +/- 1.4%)..
(Resource Enhancement and Utilization Technologies Division, Northwest Fisheries Science Center, National Marine Fisheries Service, Seattle, WA, USA, E-mail of M.B. Rust: Mike.Rust@noaa.gov)