Recent advances in fish hatchery management

Abstract

The advancement of aquaculture has often been bottlenecked because of the lack of seed, but once that bottleneck was overcome there was rapid growth. Recent examples of advances in hatchery technology leading to increased production are sea bream and Pangasius. Three areas contributing to the advancement of hatchery management are: brood stock management, induced spawning and larval feeding. Formulated diets have been developed for marine brood fish that are equal or better than the traditional raw fish diets. The importance of lipids and their composition in brood fish diets, particularly n-3 HUFAs has received much attention. The lipid composition of the brood diet is reflected in egg composition and egg quality. Protein quantity and quality in brood diets also impacts reproductive success and egg quality. The use of Gonadotropin-releasing hormone agonists (GnRHa) given as an injection or a slow release implant for induced spawning is becoming more widely used. The addition of dopamine antagonists with GnRHa may not be necessary to successfully induce spawn some species of fish. The use of GnRHa can advance the maturation of oocytes allowing such fish to be successfully induced spawned. Significant advances have been made in the development of formulated microdiets for larval fish. Such microdiets have been used successfully with young larvae reducing the need for live foods such as artemia. The quality of both live foods and formulated diets has been enriched with the use of fatty acids. Not only the quantity of n-3 HUFAs added to a diet impacts larval growth and survival but the ratios of specific n-3 HUFAs has an impact. Enrichment of live foods with amino acids can also improve larval fish growth and survival.