The
effects of photothermal manipulation on reproductive development in female
haddock Melanogrammus aeglefinus L.
D.J.
Martin-Robichaud, D.L. Berlinsky-2004
Aquaculture
Research, 35(5): 465-472
Abstract:
Haddock
(Melanogrammus aeglefinus L.) were maintained on either simulated
natural (SNP) or advanced, phase-shifted photoperiods (ADV) and reproductive
characteristics of female fish were measured throughout two reproductive
cycles. By advancing the seasonal photoperiod 8 weeks, relative to ambient
conditions, follicle development, peak levels of estradiol and initiation of
spawning were all accelerated compared with fish maintained on an SNP.
Profiles of steroid synthesis and follicular development were similar
between the two groups but the spawning period was protracted by 40 days in
the fish maintained on ADV. Ultrasound imaging proved to be an effective and
non-invasive tool for accurately assessing ovarian development throughout
the reproductive cycle. These results suggest that photoperiod manipulation
has significant potential for extending the availability of eggs and larvae
for haddock aquaculture.
(Fisheries
and Oceans Canada, Biological Station, 531 Brandy Cove Road, St Andrews, NB,
Canada E5B 2L9. E-mail of D.J. Martin-Robichaud: martin-robichaudd@mar.dfo-mpo.gc.ca)