Juveniles fed a diet containing a low or a high level of highly unsaturated fatty acids (HUFA) for 38 days were exposed to handling stress. In a ¢rst experiment, stress was applied daily for 30 days, after which the physiological and immunological variables were measured, whereas in a second experiment, stress was applied once and samples were obtained 1 and 24 h after the stressor event. Shrimp that were stressed for 30 days showed signi¢cantly lower survival, ¢nal weight and feed consumption compared with unstressed shrimp. The concentration of the high-density lipoprotein b-glucan-binding protein was signi¢cantly higher in shrimp fed the high-HUFA diet. The glucose concentration in the haemolymph was signi¢cantly higher in long-term stressed shrimp compared to controls. The lactate level in the haemolymph was signi¢cantly lower in shrimp fed the high-HUFA diet. Lactate and glucose in the haemolymph increased in the 1-h stressed shrimp, but returned to normal levels in 24-h stressed shrimp. A negative e¡ect of repeated-handling stress applied for 30 days was mainly observed on biological performance, whereas the single-stressor event had a more pronounced e¡ect on shrimp physiological and immune responses measured 1 and 24 h after the stressor. A bene¢cial role of enrich-ment with HUFA on tolerance to handling stress was observed on immune response capacity.

Almaco jack, Seriola rivoliana as well as some related species is of great interest in marine fish aquaculture. However, there are few studies about their reproduction in captivity. In this research work, reproductive performance and egg quality in two groups of adult Seriola rivoliana, caught in the wild and domesticated-F1 analyzed and compared, reared under optimal maturation conditions in a commercial private Laboratory. A total of 28 wild adult (>5 kg) were caught at La Paz Bay, Baja California Sur, Mexico, and 30 adult domesticated-F1 broodstock (>5 kg), were obtained from an original stock of 1,000 juveniles (3.5 g body weight) produced at Kona Blue (Hawaii, USA) sea farm. Fishes were transported to the Rancheros del Mar commercial private hatchery, where they were grown to adult size. Both groups were evaluated during eight months (May to December 2012) and compared in terms of reproduction performance (total number of spawning events, monthly spawning frequency, total number of eggs, total number of eggs per mL, and fertilization rate), egg biochemical composition (total proteins, total lipids, total carbohydrates, and triacylglycerides) and egg diameter. Results indicated that wild caught broostock showed a better reproductive performance in terms of fertilization rate, total number of spawning, monthly spawning frequency and total number of eggs produced. However, biochemical composition and egg diameter did not show statistical differences (P < 0.05) between two groups. The reproductive performance of broodstock and quality of eggs analyzed in this study are important traits to improve the aquaculture management of this species.

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RESUMEN.El huachinango del Pacífico, Lutjanus peru, es una especie atractiva para la acuicultura. Sin embargo, su reproducción en cautiverio en condiciones controladas no había sido factible, debido a la falta de conocimiento sobre las condiciones de manejo y el proceso reproductivo. En este estudio se evaluó la primera madurez sexual en cautiverio del huachinango del Pacífico, nacidos en el 2009 en el CIBNOR. La primera madurez sexual se determinó a los cuatro años de edad, con un peso promedio de 2.829 ± 80,9 g y longitud promedio de 540,3 ± 4,6 mm. Los primeros desoves ocurrieron en junio 2013, con la sincronización reproductiva entre machos y hembras en cautiverio, que coincidió cuando el fotoperiodo fue de 13 h luz y 11 h de obscuridad, con un aumento de temperatura del agua del estanque de 24,81 ± 1,4°C. El desove terminó en diciembre, con una disminución de temperatura 21,2 ± 1,5°C y 10 h luz. Se determinó la proporción sexual de 1:3,2 (hembra: macho). El tamaño de los huevos y la gota lipídica, disminuyeron conforme avanzó la temporada reproductiva..Se evaluó el nivel hormonal (estradiol, testosterona y 11-keto-testosterona) durante tres años. En cautiverio se determinó un ciclo reproductivo definido, en dos periodos; un periodo de reposo de diciembre a mayo, y un periodo reproductivo de junio a noviembre. Palabras clave: Lutjanus peru, primera madurez, desoves naturales, acuicultura. First sexual maturity evaluation of the Pacific red snapper (Lutjanus peru)born in captivity ABSTRACT. The Pacific red snapper Lutjanus peru, is an attractive species for aquaculture. Its reproduction in captivity under controlled conditions has not been feasible, due to the lack of knowledge on its basic reproductive biology and management conditions. For the first time, we evaluated the first sexual maturity stage of captive Pacific red snapper, born in 2009 at CIBNOR. The first sexual maturity was reached in four years with an average weight of 2,829 ± 80.9 g and average size of 540.3 ± 4.6 mm. Spawning occurred in June 2013, with a reproductive synchronization between males and females, which coincides with a photoperiod of 13 h of light and 11 h of darkness, an increase in the water ponds temperature to 24.81 ± 1.4°C. The final spawning occurred in December with a decrement of the water ponds temperature to 21.2 ± 1.5°C and 10 h light. The sex ratio was determined as 1:3.2 (female: male). The size of eggs and lipid drop decreased as the spawning season progressed. Hormone levels (estradiol, testosterone and 11-keto-testosterone), was evaluated for three years. We determined a defined reproductive cycle for the species in captivity in two periods: 1) a rest period, from December to May, and 2) a reproductive period from June to November.