Larval quality in semi-intensive mesocosm hatcheries

摘要

The high quality of larvae produced, and the low technological demands, make mesocosm hatcheries an interesting option for meeting the increasing demand for fry in developing countries.At the Asia Pacific Aquaculture Conference held last December in Vietnam, Carlos Andrade from the Centra de Maricultura da Calheta, Madeira, Portugal, presented a paper on the current state of development of fish hatchery technology using mesocosms. These are large fiberglass tanks, 40 to 110 m3 in volume, enclosing natural seawater that enables semi-intensive fish larval production while offering the environmental control and feeding conditions typically found in more intensive systems.Large systems with low larval density and high dilution of wastes imply a reduced need for water renewal and pumping. In such systems the water is of better quality and, being slow-moving, offers less hydrodynamic stress than in intensive systems. Live food is also produced naturally within the system, and can be supplemented with cultured rotifers, Artemia and formulated feeds.