| Sumario: | In Mexico, several marine fish species are subject of study as potential candidates for commercial aquaculture. Thecontrolled production of high quality larvae is essential for completion of the culture cycle in these fish. Therefore,current efforts are aimed to develop efficient larviculture techniques. To date, successful larval production has beenachieved for spotted sand bass (Paralabrax maculatofasciatus), totoaba (Totoaba macdonaldi), bullseye puffer(Sphoeroides annulatus), California flounder (Paralichthys californicus), red drum (Sciaenops ocellatus), white seabass (Atractoscion nobilis) and red snapper (Lutjanus campechanus). In other fish species some advances in larvalrearing have been reported: Pacific red snapper (L. peru) and spotted rose snapper (L. guttatus). However, highmortalities are still an obstacle for a successful larviculture in a large number of species, as in the case of commonsnook (Centropomus undecimalis), yellow snapper (L. argentiventris), leopard grouper (Mycteroperca rosacea),pompano (Trachinotus spp.) and hogfish (Lachnolaimus maximus). Because growth and survival in marine fishlarvae are mainly influenced by nutritional aspects, the information on nutritional requirements of fish larvae andnutritional quality of live food and formulated microdiets food is essential for the establishment of adequatelarviculture techniques. Feeding protocols, digestive capacity of the larvae and the importance of nutritional qualityin live food and microdiets are reviewed for their application in the larviculture of difficult-to-rear species. Feedingprotocols with the use of microalgae, rotifers and Artemia nauplii are currently used for most species. At firstfeeding, adequate live food density and particle size are essential for fish larvae. The use of small strain rotifers andcopepods has allowed improvements in fish survival during this critical stage. Once successful first feeding isachieved, significant higher fish growth and survival have been obtained with the use of live food enriched withessential fatty acids (i.e. HUFA) when compared to non-enriched rotifers or Artemia. Application of specificmethods for production and storage of live food, such as Artemia cysts decapsulation and live Artemia cold-storagehave improved experimental hatchery outputs. As for weaning microdiets, several formulated microdiets have beenprepared using various manufacturing techniques (i.e. microbound and microencapsulation) and have been testedwith good results in some species. However, the lower ingestion rate of microdiets compared to live food is a majorproblem to be tackled. The use of highly digestible protein sources, intact or predigested, has improved microdietassimilation.
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