Publicação
Evaluation of Paracentrotus lividus (Lamarck, 1816) exotrophic larvae as live feed for marine decapod crustacean larvae
| Resumo: | In the present study, we have evaluated 4‐arm exotrophic larvae of sea urchin Paracentrotus lividus (Echinodermata: Echinoidea) as live feed in marine decapod crustacean larviculture, in comparison to Artemia spp. naupliar stages, a commonly used live prey in marine hatcheries. We therefore investigated several key parameters to assess the potential of P. lividus plutei as live feed for crustacean larvae, namely: 1) broodstock diet manipulation in order to obtain both quantitative and qualitative year round production of 4‐arm echinoplutei, free from environmental and reproductive seasonal constraints; 2) best possible biotic conditions to perform sea urchin in vitro fertilization, namely sperm:egg ratios and egg concentrations, and its relation to early stage segmentation and larvae development; 3) mass production possibility in terms of larvae media culture conditions, plutei stocking densities and larvae feed and enrichment; and acceptability as live feed by predator larvae (Lysmata seticaudata, Palaemon elegans, Maja brachydactyla, Pachygrapsus marmoratus and Xantho incisus). Additionally, we studied the possibility to differentiate P. lividus broodstock sex by means of a spine external morphological characteristic. Under controlled laboratory conditions, percent egg fertilization above 99% and high values for percent normal development (≥85%) were obtained when captive breed P. lividus broodstock was fed an inert diet based upon maize and wheat flour mixture. Whole egg total amino acid composition was similar between P. lividus fed this inert diet and wild caught organisms. Enrichment potential in terms 4‐arm plutei fatty acid profile and lipid content was possible through manipulation of the lipid source chosen for captive P. lividus broodstock diet. Sperm:egg ratios were found to influence percent egg fertilization and segmentation development after 90 minutes post‐fertilization, but not plutei total length, post‐oral arm length and normal percent larvae development. Water renewal (every 2 days) during P. lividus larviculture was found to be an essential abiotic culture condition to sustain plutei development and survival until 18 days post‐fertilization. All plutei larval feeds (live microalgae, inert microdiets, single or mixed provided), supported P. lividus larvae growth and survival until 18 days post‐fertilization (DPF), with D. tertiolecta being found to be the most appropriate diet in terms of larvae development and survival outcome. When cultured at a initial stocking density of 40 plutei.ml‐1, inert microdiets were unable to sustain P. lividus plutei survival to 10 DPF. Plutei survival was found to be inversely correlated with increasing culture densities. Paracentrotus lividus plutei enrichment with Algamac 3050 flake, was found to cause mass mortality at 5 and 10 DPF. Paracentrotus lividus exotrophic 4‐arm plutei was ingested and preyed by 4 (Lysmata seticaudata, Maja brachydactyla, Pachygrapsus marmoratus and Xantho incisus) out of 5 crustacean larvae tested, but were unable to sustain complete larvae development and survival to settlement of L. seticaudata, M. brachydactyla and P. marmoratus species. No apparent advantage of P. lividus 4‐arm plutei as live feed for marine crustacean decapod larvae was found in comparison to Artemia spp.. Finally, the analysed spine morphological characteristic, as a tool for sex differentiation between P. lividus adults, does not allow accurate and feasible results. |
|---|---|
| Autores principais: | Repolho, Tiago |
| Assunto: | Paracentrotus lividus Larvas Crustáceos Teses de doutoramento - 2012 |
| Ano: | 2012 |
| País: | Portugal |
| Tipo de documento: | tese de doutoramento |
| Tipo de acesso: | acesso aberto |
| Instituição associada: | Universidade de Lisboa |
| Idioma: | inglês |
| Origem: | Repositório da Universidade de Lisboa |
| Resumo: | In the present study, we have evaluated 4‐arm exotrophic larvae of sea urchin Paracentrotus lividus (Echinodermata: Echinoidea) as live feed in marine decapod crustacean larviculture, in comparison to Artemia spp. naupliar stages, a commonly used live prey in marine hatcheries. We therefore investigated several key parameters to assess the potential of P. lividus plutei as live feed for crustacean larvae, namely: 1) broodstock diet manipulation in order to obtain both quantitative and qualitative year round production of 4‐arm echinoplutei, free from environmental and reproductive seasonal constraints; 2) best possible biotic conditions to perform sea urchin in vitro fertilization, namely sperm:egg ratios and egg concentrations, and its relation to early stage segmentation and larvae development; 3) mass production possibility in terms of larvae media culture conditions, plutei stocking densities and larvae feed and enrichment; and acceptability as live feed by predator larvae (Lysmata seticaudata, Palaemon elegans, Maja brachydactyla, Pachygrapsus marmoratus and Xantho incisus). Additionally, we studied the possibility to differentiate P. lividus broodstock sex by means of a spine external morphological characteristic. Under controlled laboratory conditions, percent egg fertilization above 99% and high values for percent normal development (≥85%) were obtained when captive breed P. lividus broodstock was fed an inert diet based upon maize and wheat flour mixture. Whole egg total amino acid composition was similar between P. lividus fed this inert diet and wild caught organisms. Enrichment potential in terms 4‐arm plutei fatty acid profile and lipid content was possible through manipulation of the lipid source chosen for captive P. lividus broodstock diet. Sperm:egg ratios were found to influence percent egg fertilization and segmentation development after 90 minutes post‐fertilization, but not plutei total length, post‐oral arm length and normal percent larvae development. Water renewal (every 2 days) during P. lividus larviculture was found to be an essential abiotic culture condition to sustain plutei development and survival until 18 days post‐fertilization. All plutei larval feeds (live microalgae, inert microdiets, single or mixed provided), supported P. lividus larvae growth and survival until 18 days post‐fertilization (DPF), with D. tertiolecta being found to be the most appropriate diet in terms of larvae development and survival outcome. When cultured at a initial stocking density of 40 plutei.ml‐1, inert microdiets were unable to sustain P. lividus plutei survival to 10 DPF. Plutei survival was found to be inversely correlated with increasing culture densities. Paracentrotus lividus plutei enrichment with Algamac 3050 flake, was found to cause mass mortality at 5 and 10 DPF. Paracentrotus lividus exotrophic 4‐arm plutei was ingested and preyed by 4 (Lysmata seticaudata, Maja brachydactyla, Pachygrapsus marmoratus and Xantho incisus) out of 5 crustacean larvae tested, but were unable to sustain complete larvae development and survival to settlement of L. seticaudata, M. brachydactyla and P. marmoratus species. No apparent advantage of P. lividus 4‐arm plutei as live feed for marine crustacean decapod larvae was found in comparison to Artemia spp.. Finally, the analysed spine morphological characteristic, as a tool for sex differentiation between P. lividus adults, does not allow accurate and feasible results. |
|---|