The potential of tropical
paracalanid copepods as live feeds in aquaculture
A.D.
McKinnon, S. Duggan, P.D. Nichols, M.A. Rimmer, G. Semmens, B. Robino-2003
Aquaculture, 223(1-4): 89-106
Abstract:
The small calanoid copepods Bestiolina similis
and Parvocalanus crassirostris (Paracalanidae) are compared to Acartia
sinjiensis, a species of the copepod genus most commonly cultured to
provide larval diets for tropical snappers and groupers. All species are
easily maintained in culture, though cultures of Acartia spp. are
easier to establish because of the positive phototactic behaviour of this
genus. B. similis and P. crassirostris are smaller than A.
sinjiensis, and consequently, their developmental stages are more suited
to larval fish requiring small prey items. In addition, siphon-avoidance
experiments indicated that adults of these species were more vulnerable to
predation, though this was not the case for juvenile copepods. Egg
production was maximised with larger algal cells, especially Rhodomonas
sp. and Heterocapsa niei: B. similis fed H. niei
achieved the highest egg production rates (48 eggs female-1 day-1).
Lipid composition of all species was low and variable (11–26 mg g-1)
under our culture conditions, in contrast to results from temperate copepod
species or from wild-caught copepods. All three species studied had
DHA/EPA/ARA ratios that met or exceeded those recommended for marine larval
fish feeds (DHA/EPA/ARA-14:3:1, 20:9:1 and 25:6:1 for A. sinjiensis, P.
crassirostris and B. similis, respectively). On the basis of size
of developmental stages, susceptibility to predation, growth rate and
nutritional composition, B. similis was the best candidate for larval
fish diets.