Utilización de cangrejo y harinas en un pienso para pulpo común Octopus vulgaris

The present work evaluates whether the addition of 2 species of crab (Portunus pelagicus and Grapsus grapsus) as attractants (10%) in experimental moist diet based in discarded bogue (Boops boops) may increase ingestion and growth in O. vulgaris. Besides, another diet based on flour, made from discarded bogue and G. grapsus, was tested. Finally, a 40-60% discarded bogue-crab P. pelagicus was provided as a control diet. Four male octopuses, kept The present work evaluates whether the addition of 2 species of crab (Portunus pelagicus and Grapsus grapsus) as attractants (10%) in experimental moist diet based in discarded bogue (Boops boops) may increase ingestion and growth in O. vulgaris. Besides, another diet based on flour, made from discarded bogue and G. grapsus, was tested. Finally, a 40-60% discarded bogue-crab P. pelagicus was provided as a control diet. Four male octopuses, kept in PVC net cages in the same tank, were fed each diet for 8 weeks and several parameters were calculated: absolute growth rate (AGR, g./day), standard feeding rate (SFR, %/day) and feed efficiency (FE). The addition of crab to the diet under the conditions described did not improve ingestion, growth or feed efficiency in this species, while the flour based diet generated negative growth.

Evaluación de dos anestésicos y metodología de marcaje individual con microchip subcutáneo en Octopus vulgaris

[EN]The present work evaluates, on one hand, two anaesthetic agents to facilitate octopus handling concluding that a 1.5% of ethanol (96%) in sea water (22ºC) shows rapid anaesthetic-recovery time, indicating its suitability for this species. On the other hand, a protocol for implanting Octopus vulgaris with subcutaneous PIT tags is established and after 10 weeks a 94% retention was found with 100% survival. Retention rises to 98,6% when tagging animals weighing more than 500 g.

Crecimiento individual de Octopus vulgaris (Cuvier, 1797) alimentado con pienso húmedo experimental y boga (Boops boops, L. 1758)

[EN]The present work pretends to be the first step towards the development of a commercial diet for Octopus vulgaris. A one month experiment evaluated growth on two treatments, a wet experimental diet and a control (bogue), obtaining a daily growth rate of 1,6 and 16 g/day respectively. Octopuses were tagged and a better growth tendency was found in middle size animals in each experimental tank

Optimización de las condiciones de engorde y avances en el conocimiento de los requerimientos nutricionales de pulpo común Octopus vulgaris (Cuvier, 1797)

Programa de Doctorado, Acuicultura: Producción controlada de animales acuáticos

Effect of different live prey, Grapsus grapsus Linnaeus 1758 and Plagusia depressa Fabricius, 1775 zoeas,over histology and biochemical composition of common octopus, octopus vulgaris Cuvier, 1797 paralarvae

[EN] Since paralarval rearing is still the main bottleneck for the development of octopus culture, the aim of the present study was to obtain some information on the feeding strategy and nutritional requirements during paralarval stage. For that purpose just hatched out octopus paralarvae were fed with live preys in three different combinations, trying to match their natural food: Enriched Artemia metanauplii, Grapsus grapsus zoeas supplemented with enriched Artemia, and Plagusia depressa zoeas supplemented with enriched Artemia. Paralarval treatments were carried out during 28 days in triplicates; fibre glass 120 l tanks in flow through system were used. Growth, in terms of dry body weight, mantle length and width, was determined each seven days. A histological study of the paralarval development was carried out. Biochemical composition of preys and paralarvae were determined. Growth was significantly better in paralarvae fed with zoeas and Artemia than in those fed only with Artemia, from day 8 after hatching. Besides a clear effect on the digestive gland histology morphology was observed.

Crecimiento y supervivencia de paralarvas de O. vulgaris cultivadas bajo diferentes intensidades de luz.

[EN] Paralarval rearing constitutes the main bottleneck to the complete development of octopus culture. This paper try to optimise the larval rearing conditions of Octopus Paralarvae, testing the effect of light intensity (1000, 3000 and 6000 lux ) over growth and paralarval survival. Four fibber glass tanks, 100 litter capacity with an initial density of 20 ind./litter were used for each treatment. All light treatments were fed with the same protocol, just hatching Maja Squinado Zoeas and Artemia metanaulios (72 hours)enriched with a commercial emulsion (Red Pepper Paste, Bernaqua, bva; Belgium). Better growth and survival were found with the highest light intensity treatment.

The effects of supplementation of decapod zoea to Artemia basal diet on the digestive gland histology and the fatty acid composition in common octopus (Octopus vulgaris) paralarvae.

[EN]The present study aimed to evaluate the effect of the supplementation of different crab zoeas to enriched Artemia basal diet for O. vulgaris paralarvae during the first month of life. Paralarvae were fed using: enriched Artemia nauplii alone and Artemia co-fed with either first zoea stages of Grapsus adscensionis or Plagusia depressa. The experiment was carried out over a period of 28 days, in 0.12 m3 tanks with a flow-through rearing system. Growth in dry weightas well as mantle length and width were assessed weekly. Additionally, prey and paralarvae fatty acid composition and digestive gland (DG) histology were evaluated.