This paper, therefore, is an initial study to develop a broodstock diet for the mangrove red snapper to ensure consistent production of highest-quality eggs and larvae to support mass production of fry in the hatchery.Ī homogenous stock of 7-year-old mangrove red snapper ( Lutjanus argentimaculatus) broodstock initially from hatchery-produced juveniles were kept in two units of 6-m diameter×3 m deep floating net cages at the Igang Marine Substation of the Southeast Asian Fisheries Development Center's Aquaculture Department (SEAFDEC/AQD) in Central Philippines. However, there are variations in egg and larval quality and larval survival in the hatchery remains poor (<1%) (Duray et al., 1996).įor the mangrove red snapper, there is no information available on effects of broodstock nutrition regarding reproductive performance. Presently, the mangrove red snapper sexually mature and spawn spontaneously in concrete tanks and floating net cages at the Southeast Asian Fisheries Development Center's Aquaculture Department (SEAFDEC/AQD) Emata, 1996, Emata et al., 1999. Thus, a reliable breeding and fry production technique must be developed to ensure consistent production of good quality fry to meet the demand of the industry. This limits the sustainability of its aquaculture. However, the culture of this species is still exclusively dependent on wild fry where the supply is limited, seasonal and unpredictable. In recent years, the aquaculture of the mangrove red snapper has become immensely popular in Southeast Asia and Australia due to its high market price Liao et al., 1995, Wong, 1995, Chou and Lee, 1997. Further studies should focus on the specific nutrients that can ensure consistent production of high quality eggs and larvae of the mangrove red snapper to support its aquaculture. The results clearly indicate the improvement of reproductive performance of mangrove red snapper fed practical diet. Also, survival activity index (4.08) of broodstock fed practical diet was higher than that of broodstock fed raw fish (2.97). However, broodstock fed the practical diet had higher mean cumulative survival rate of eggs to normal larvae (40.4%) than that of broodstock fed raw fish (35.2%). Mean percent of egg viability, hatching rates and percent of normal larvae did not vary between the two groups. Broodstock fed practical diet had total egg production of 82.34 million from 68 spawns for two spawning seasons while broodstock fed raw fish produced 77.64 million eggs from 66 spawns. Reproductive performance of mangrove red snapper broodstock fed practical diet ( n=14 females) was enhanced in comparison to those fed raw fish ( n =12 females). A practical broodstock diet (39% protein, 8.6% lipid) was formulated for the mangrove red snapper as part of a project to ensure consistent production of good quality eggs and larvae through broodstock nutrition.
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