Two 10‐day hatchery experiments were conducted to evaluate s‐type (Hawaiian strain) and ss‐type (Thailand strain) rotifers Brachionus plicatilis and cryogenically preserved oyster Crassostrea gigas trochophores as first feeds for larval Nassau grouper Epinephelus striatus. Newly hatched grouper larvae were reared at densities of 11.2–20.8/L in 500‐L tanks at 36–38 ppt salinity, 25–26 C, and under a 11‐h light: 13‐h dark photoperiod. Beginning on day 2 posthatching (d2ph), prey were maintained at a density of 20 individuals/mL, while phytoplankton (Nanochloropsis oculata) was maintained at 500 × 103 cells/mL. In experiment 1, survival and growth were higher (P < 0.05) for fish fed small s‐type rotifers (mean lorica length = 117 μm; fish survival = 7.96%) selected by sieving than for fish fed non‐selected rotifers (mean lorica length = 161 μm; fish survival = 2.13%). These results demonstrated the advantage of small prey size and suggested that super‐small (ss‐type) rotifer strains would be beneficial. In experiment 2, three feeding regimens were compared: 1) ss‐type rotifers (mean lorica length = 147 μm); 2) oyster trochophores (mean diameter = 50 μm) gradually replaced by ss‐type rotifers from d5ph; and 3) a mixed‐prey teatment of 50% oyster trochophores and 50% ss‐type rotifers. Survival was higher (P < 0.05) for larvae fed mixed prey (15.6%) than for those fed rotifers (9.73%) or trochophores and rotifers in sequence (2.55%), which also showed the slowest growth. Oyster trochophores, although inadequate when used exclusively, enhanced survival when used in combination with rotifers, possibly by improving size selectivity and dietary quality. In a pilot‐scale trial, larvae were cultured through metamorphosis in two 33.8‐m3 outdoor tanks. Fertilized eggs were stocked at a density of 10 eggs/L and larvae were fed ss‐type rotifers from d2ph‐d20ph, newly hatched Artemia from d15ph‐d18ph, 1‐d‐old Artemia nauplii from d18ph‐d62ph. Survival on d62ph was 1.17%, with a total of 5,651 post‐metamorphic juveniles produced.

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Se obtuvo el desove de dos hembras silvestres de la cabrilla sardinera, Mycteroperca rosacea, mediante el uso de la hormona Gonadotropina Coriónica Humana (HCG) inoculada en dos dosis: la primera de 1000 UI/kg y la segunda de 500 UI/kg, separadas por 24 h. De las cuatro hembras tratadas, dos tuvieron una respuesta positiva al desove, liberando aproximadamente 40,000 huevos/pez, que fueron fecundados con el esperma de los machos que se encontraban maduros. La tasa de fecundación obtenida de las dos hembras fue de 10% y 0%. Se describe el desarrollo embrionario completo, así como las características morfológicas de los huevos y las larvas hasta la primera alimentación. Los huevos esféricos, transparentes y pelágicos, presentaron un diámetro de 872.8 ± 15.4 µm (rango de 850.4 a 912.5 µm) y una gota lipídica con un diámetro de 177.3 ± 7.0 µm.

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