The role of microalgae in aquaculture: situation and trends
A. Muller-Feuga-2000
Journal of Applied Phycology, 12 (3-5) : 527-534
(from Current Contents)
Abstract:
Algae are utilized diversely in aquaculture, but
their main applications are related to nutrition. They are used in toto, as
a sole component or as a food additive to supply basic nutrients, color the
flesh of salmonids or for other biological activities. The need for
nutritional sources safer than traditional animal products has renewed
interest in plants in general and algae in particular. This report deals
principally with the nutritional role of microalgae in aquaculture. The
larvae of molluscs, echinoderms and crustaceans as well as the live prey of
some fish larvae feed on microalgae. Though attempts have been made to
substitute inert particles for these micro-organisms which are difficult to
produce, concentrate and store, only shrimp and live prey for fish will
accept inert food, and only shrimp accept it fully. Several studies have
confirmed that a live, multi-specific, low-bacteria microalgal biomass
remains essential for shellfish hatcheries. Major advances are expected from
new production system designs and operations, from batch-run open tanks to
more sophisticated continuously run and closed loop reactors. Studies are
underway to simplify hatchery operations by replacing biomass produced
on-site with run-times by that produced and preserved elsewhere. Although
still promising, they have not given rise, so far, to any application for
molluscs. Other applications of microalgae in aquaculture, from green water
to making salmon flesh pinker, are examined. Whether produced on or
off-site, there remains the question of cost effectiveness of microalgal
production systems. This can only be achieved by substantial upscaling and
improved quality control.
(IFREMER, BP 21105,
F-44311 Nantes, France, e-mail: amuller@ifremer.fr)