2 resultados para feeding habits

em Acceda, el repositorio institucional de la Universidad de Las Palmas de Gran Canaria. España


Relevância:

60.00% 60.00%

Publicador:

Resumo:

On-growing of Octopus vulgaris fed different feeds has shown promising results. Nevertheless, since the minimum legal size for octopus fisheries in spain i sin most of experimental ongrowing of this species an average weight over 750-1000kg was utilized with g (and little research has been conducted in order to evaluate the effect of these diets on smaller individuals. The present work evaluates the effect of 3 diets based on bogue, obtained as ?discarded? species from local fish farms, on ingestion and growth of O. vulgaris weighing 400 g. The 1st diet was composed by discarded bogue, the 2nd diet by a 40-60% discarded bogue-crab Portunus pelagicus and the 3rd diet was presented as a moist diet based on discarded bogue. A triplicate of four octopuses per treatments, male:female 1:1, were kept in circular 400 l tanks and fed each diet for 4 weeks. Absolute growth rate (AGR, g./day), standard feeding rate (SFR, %/day) and feed efficiency (FE) were calculated. The addition of crab to the diet increased SFR which underlines different feeding habits when compared with 0.8-1 kg octopuses. Lower growth and higher FE was recorded with the moist diet, probably due to high disintegration of this kind of feed.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

[EN] Brine shrimp nauplii (Artemia sp.) are used in aquaculture as the major food source for many cultured marine larvae, and also used in the adult phase for many juvenile and adult fish. One artemia species, Artemia franciscana is most commonly preferred, due to the availability of its cysts and to its ease in hatching and biomass production. The problem with A. franciscana is that its nutritional quality is relatively poor in essential fatty acids, so that it is common practice to enrich it with emulsions like SELCO and ORIGO. This “bioencapsulation”, enrichment method permits the incorporation of different kinds of products into the artemia. This brine-shrimp’s non-selective particle-feeding habits, makes it particularly suitable for this enrichment process. The bioencapsulation is done just prior to feeding the artemia to a predator organism. This allows the delivery of different substances, not only for nutrient enrichment, but also for changing pigmentation and administering medicine. This is especially useful in culturing ornamental seahorses and tropical fish in marine aquaria In this study the objectives were to determine, the relative nutrient value of ORIGO and SELCO as well as the optimal exposure to these supplements prior to their use as food-organisms.