Larval development and fatty acid composition of <i>Ostrea edulis</i>
 (L.) fed four different single diets from conditioning to pre-settlement

The microalgae Rhodomonas sp. is known as an excellent feed source for live feed organisms such as copepods. The main benefits of feeding Rhodomonas to live feed animals are attributed to the relative high polyunsaturated fatty acid (PUFA) level, the combination of containing both docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), and the ratio between these fatty acids (FA). It has been shown that microalgae are able to accumulate valuable metabolites, such as lipids, under adverse conditions. The easiest and most inexpensive method to induce stress to microalgae is through nitrogen (N) starvation. In this study, the effect of N-starvation on biomass concentration, cell volume, and cellular composition, such as fatty acid concentration and composition, and phycoerythrin (PE) concentration of Rhodomonas sp. during a period of 8 days, was investigated. The research was divided into two stages. In the first (growth) stage, Rhodomonas sp. was cultivated in small 400 ml photobioreactors (Algaemist-S) under optimal conditions in turbidostat mode, which reached a biomass concentration of 1.5 gDW L −1 and dilution rate of 1.3 d −1. Samples were taken every 24 h for cell density and volume and productivity measurements in order to ensure a healthy and stable culture. In the next stage (N-starvation), the biomass was washed and transferred in a reactor filled with N-depleted medium. During N-starvation, samples were taken for biomass concentration, cell volume, PE and FA composition. The results of this study demonstrate that the lipid content increased significantly from 9% (t = 0 h) to 30% (t = 120 h) of the dry weight. After 120 h of N-starvation, the total FA content of Rhodomonas sp. remained stable for the remainder of the experiment (next 72 h). The highest increase of the FA concentration was represented by C16:0, C:18:1, C18:2, and C18:3, with highest concentrations after 120 h of starvation. The maximum EPA and DHA concentrations were observed after 48 h of starvation, while the maximum DHA to EPA ratio was detected at the end of the starvation.

show abstract

“…and Scenedesmus sp. (Pratoomyot et al, 2005;González-Araya et al, 2012;González-Araya and Robert, 2018). The SFA composition or Rhodomonas sp.…”

Section: Fatty Acid Compositionmentioning

confidence: 99%

The Effect of Nitrogen Starvation on Biomass Yield and Biochemical Constituents of Rhodomonas sp.

2020

View full text Add to dashboard Cite

show abstract

“…muelleri (long setae), T. lutea and P. lutheri provided the best results registered in monoalgal experiment of this study (at least in growth and survival). Similar acceptance reports are found when those flagellates are included in the diet in experiments with Crassostrea gigas (Rico‐Villa et al., 2006; Wang, Li, Zhang, & Yu, 2018), C. virginica (Babinchak & Ukeles, 1979), Pecten maximus (Le Pennec & Rangel‐Dávalos, 1985), Argopecten ventricosus (Lora‐Vilchis & Maeda‐Martínez, 1997), Pteria sterna (Martínez‐Fernández et al., 2004), Ruditapes decussatus (Aranda‐Burgos et al., 2014), Placopecten magellanicus (Gouda, Kenchington, Hatcher, & Vercaemer, 2006), Pinctada margaritifera (Martínez‐Fernández, Acosta‐Salmón, & Southgate, 2006) and Ostrea edulis (González‐Araya & Robert, 2018).…”

Section: Discussionmentioning

confidence: 99%

Microalgal diet evaluation in the larval development and substrate selection for settlement in the rock oysterStriostrea prismatica (Gray, 1825)

et al. 2020

View full text Add to dashboard Cite

Monoalgal and bialgal diet were tried in 2 stages of larval development of Striostrea prismatica: phase I from mixotrofic to early umbonated veliger larva and phase II until eyespot larvae. The monoalgal diets in phase I were Tisochrysis lutea, Pavlova lutheri and Nannochloropsis sp. In phase II, Tetraselmis suecica, T. chuii, Chaetoceros gracilis and Ch. muelleri were incorporated. The bialgal diets (combination of P. lutheri + Ch. gracilis in proportions 1:3, 1:1 and 3:1) were chosen according to the results of the monoalgal trials and were evaluated against the classic diet = control (T. lutea + Ch. gracilis). The microalgae size and their fatty acid composition were determined. We recommend the combination T. lutea + Ch. gracilis, initially using T. lutea for mixotrophic larvae (6 days Post Fertilization‐PF), then incorporating Ch. gracilis in a ratio of 1:1 until completing phase I (8–10 PF). In phase II, the ratio should change to 1:3 until larvae with eyespot are obtained (18–20 PF). Suggestions were based on the higher demand for DHA in initial larvae and the need for EPA from the early umbonated phase. Finally, as a third experiment, microsubstrates (pieces of shells, sandpaper, polycarbonate and ground rubber) were evaluated to promote the settlement of pediveliger larvae. A settlement of 20% was obtained in pieces of shells of the same species. We consider that the settlement technology has not been optimized; therefore, evaluations directed at the behaviour of the species are recommended.

show abstract

“…Tritar, Prieur, & Weiner, 1992;Wilson, 1980) or relates to topics of importance to aquaculture (e.g. González-Araya & Robert, 2018;Labarta, Fernández-Reiriz, & Pérez-Camacho, 1999;Mesías-Gansbiller et al, 2013), which may differ from those of oyster reef restoration. For example, the disease and invasive nonnative species issues of taking oysters from aquaculture to the table market are very different from those of taking oysters from aquaculture and placing them back into the marine environment elsewhere.…”

Section: Discussionmentioning

confidence: 99%

Forty questions of importance to the policy and practice of native oyster reef restoration in Europe

Ermgassen

Bonačić

Boudry

et al. 2020

Aquatic Conservation

View full text Add to dashboard Cite

Oyster reefs are among the most threatened marine habitats globally. In Europe, oyster reefs have been extirpated from most locations within their historical range. Active restoration of the native oyster (Ostrea edulis) in Europe has grown substantially in recent years. In sharing experiences between oyster restoration projects in Europe at the Native Oyster Restoration Alliance conference, NORA2, in Edinburgh in May 2019, it became apparent that a number of similar barriers are experienced. This study identified the top 40 questions, which, if answered, would have the greatest influence on the policy and practice of oyster restoration in Europe. Initially 71 people were consulted across 28 institutions and 11 European countries to generate 194 questions. An established process of one round of pre‐workshop voting followed by a one‐day online workshop and two post‐workshop rounds of voting resulted in the final 40 questions. Questions were broadly grouped into the following 10 themes: baselines, site selection, restoration methods, quantifying benefits, disease management, biosecurity, genetic diversity and population differentiation, policy and management, novel technologies, and current and future threats. We anticipate that this list will provide a starting point for developing collaborative projects across the NORA network, as well as assisting policy makers and funders with identifying key areas that need to be addressed in order to overcome existing barriers to scaling up oyster restoration in Europe.

show abstract

Larval development and fatty acid composition of Ostrea edulis (L.) fed four different single diets from conditioning to pre-settlement

Cited by 14 publications

References 40 publications

The Effect of Nitrogen Starvation on Biomass Yield and Biochemical Constituents of Rhodomonas sp.

The Effect of Nitrogen Starvation on Biomass Yield and Biochemical Constituents of Rhodomonas sp.

Microalgal diet evaluation in the larval development and substrate selection for settlement in the rock oysterStriostrea prismatica (Gray, 1825)

Forty questions of importance to the policy and practice of native oyster reef restoration in Europe

Contact Info

Product

Resources

About