Gercende B Courtois de Viçose (original) (raw)

Papers by Gercende B Courtois de Viçose

Aquaculture Nutrition

A 12-day experiment was conducted to investigate the effects of Artemia enrichment with two exper... more A 12-day experiment was conducted to investigate the effects of Artemia enrichment with two experimental microalgal emulsions (formulated with selected fatty acid contents) on Penaeus vannamei postlarvae. For this purpose, 405,000 postlarvae (stage 1) were obtained from a commercial hatchery in Santa Elena, Ecuador, and distributed into nine fiberglass tanks. Postlarvae were fed for 12 days with three experimental diets (three tanks per treatment): treatment A (Artemia enriched with experimental microalgal emulsion A and dry diet), treatment B (Artemia enriched with experimental microalgal emulsion B and dry diet) and nonenriched Artemia (Artemia without enrichment and dry diet). At the end of the experiment, length (mm), coefficient of variation of population sizes, number of postlarvae in a gram of weight (PL-gram), biochemical composition, fatty acid profile, hepatopancreas perimeter, and histopathological hepatopancreas status of P. vannamei postlarvae (stage 12) were analyzed. ...

Frontiers in Marine Science

The production of cultured limpets is a recent research field contributing to aquaculture diversi... more The production of cultured limpets is a recent research field contributing to aquaculture diversification, focusing on low trophic species while reducing the carbon footprint. Limpets are gastropods that colonize rocky substrates and are mostly present on tidal and subtidal shores. This animal group is in high commercial demand and is endangered in several regions. The aquaculture production of limpets has been traditionally challenging. The most successful reproduction method has been gonadal dissection, as artificial spawning induction has shown limited success to date. Moreover, methods for larval culture, settlement, and juvenile growth have been poorly developed and remain largely unknown. In recent years, advances in this field have led to the optimization of methods to enhance larval production, larval culture, settlement induction of competent larvae, and management of post-larvae and juveniles. The present manuscript reviews these advances, obtained within the framework of ...

Aquaculture Reports, 2021

Hatchery production is critical to the successful aquaculture of a species. This study describes ... more Hatchery production is critical to the successful aquaculture of a species. This study describes the first captive breeding and reports on the embryonic development and early larval stages of the sea cucumber Holothuria sanctori, a species native to the Mediterranean and eastern Atlantic. Various induction methods were applied to obtain spawning in adult H. sanctori specimens; gametes were obtained from a spontaneous spawning event and from broodstock induced by mechanical shock coupled with algal stimulation. Fertilized eggs were then cultured at two different densities (0.3 egg/ml and 1 egg/ml) and fed two microalgae densities (5 × 10 3-2 × 10 4 cells/ml and 1 × 10 4-4 × 10 4 cells/ml) from the microalgae Nannochloropsis sp. and Amphora sp. and larval growth was recorded. Embryonic and larval development of H. sanctori were monitored on a daily basis for one month and auricularia larval growth was registered at days 5, 10, 15, and 20 after fertilization. The embryonic and larval stages were observed up to the late auricularia stage (14 days after fertilization). The best larval growth was observed at the lower egg and algal densities.

Aquaculture International, 2012

Marine Biotechnology, 2021

The phylum Mollusca represents one of the largest groups of marine invertebrates. Nowadays, mollu... more The phylum Mollusca represents one of the largest groups of marine invertebrates. Nowadays, molluscan shellfish belonging to the classes Bivalvia and Gastropoda are of commercial interest for fisheries and aquaculture. Although bioactive properties of bivalve molluscs have been widely investigated and several dietary supplements have been brought to the market, the bioactive potentialities of marine gastropods are poorly documented. The present study investigated the bioactive properties of tissue extracts derived from Haliotis tuberculata coccinea, or "European abalone," an edible abalone species distributed in the Mediterranean Sea and the northeast Atlantic Ocean. A bioactive organic compound-rich extract was obtained using ethyl acetate as extracting solvent. It showed antimicrobial activity towards the methicillin-resistant Staphylococcus epidermidis strain RP62A, the emerging multi-drug-resistant Stenotrophomonas maltophilia D71 and Staphylococcus aureus ATCC 6538P, being the most sensitive strain. It also showed anthelmintic activity, evaluated through the toxicity against the target model helminth Caenorhabditis elegans. In addition, the ethyl acetate extract demonstrated a selective cytotoxic activity on the cancer cell lines A375, MBA-MD 231, HeLa, and MCF7, at the concentration of 250 µg/mL. The fatty acid composition of the bioactive extract was also investigated through FAME analysis. The fatty acid profile showed 45% of saturated fatty acids (SAFA), 22% of monounsaturated fatty acids (MUFA), and 33% of polyunsaturated fatty acids (PUFA). The presence of some biologically important secondary metabolites in the extract was also analysed, revealing the presence of alkaloids, terpenes, and flavonoids.

Phuket Marine Biological Center Special Publication 20, 1999

Singapore waters are heavily loaded with sediments, caused mainly by three decades of land reclam... more Singapore waters are heavily loaded with sediments, caused mainly by three decades of land reclamation and constant dredging for harbor and navigational purposes. Although all domestic sewage from mainland Singapore is treated, the waters also contain relatively high levels of nutrients, possibly due to heavy shipping activities, and other anthropogenic sources from the Johore and Malacca Straits. Ammonium and phosphate concentrations have been found to be 15 and 8 times higher, respectively, compared to levels at the Great Barrier Reef. The high sedimentation and nutrient levels have had a major effect on marine life in Singapore, especially coral reefs. Recent surveys made around the southern islands of Singapore recorded very few giant clams, compared to observations made two decades ago. Apart from the environmental issues, the unmanaged collection in the past also led to the serious decline of the giant clam population today. Consequently, one of the aims of the Tropical Marine Science Initiative of the National University of Singapore, is a reseeding of the reefs in Singapore's Marine Nature Areas.
The rehabilitation of giant clams in Singapore will be launched with the following aim:
a. Breed Tridacna squamosa, Tcrocea, Tmaxima and Hippopus hippopus in enriched waters;
b. Study the settlement stage of giant clam larvae;
c. Study the effects of nutrients on the early stages of clams such as the effects on survival at metamorphosis and settlement stages (the most critical phases) and the effects on growth of juveniles;
d. Observe animal physiology under high nutrients and sedimentation rates such as the observation of clearance and filtration rates in waters with high sedimentation rates and the observation of photosynthetic and filter feeding processes under high nutrient levels; and
e. Observe major stress signals due to water quality criteria.

Aquaculture international, 2013

The effect of egg density on embryonic development and larval quality as well as the lipid and fa... more The effect of egg density on embryonic development and larval quality as well as the lipid and fatty acid contents (eicosapentaenoic acid, EPA; docosahexaenoic acid, DHA) of cultured microalgae fed to Perna perna larvae was studied under controlled conditions to provide information needed for development of an experimental hatchery. Embryonic development followed the common sequence exhibited by other bivalves. D-larva stage was attained 40-44 h post-fertilisation at 21 ± 1°C. The umbo-stage was reached in 11 days, and pediveliger larvae were observed 26 days post-fertilisation. Low egg density (range 20-100 eggs cm-2) produced high proportions of normal D-larvae. Larval development showed two growth phases: 1st-the mixotrophic stage and 2nd-the exotrophic stage where the composition of diets had significant effects on larval growth with higher rates in larvae fed with the mixed microalgae (Isochrysis galbana ? Chaetoceros calcitrans, I. galbana ? Phaeodactylum tricornutum and I. galbana ? Skeletonema costatum) in comparison with the monospecific diet (I. galbana). Fatty acid analysis showed that larval growth and survival were strongly influenced by proportions of dietary DHA and EPA. These results indicate that DHA and EPA are the key factors in determining larval performance, considerably more than the total amount of other fatty acids.

Impact, 2017

Researchers Ricardo Haroun and Gercende Courtois de Viçose together with the ERA Chair Sachi Kaus... more Researchers Ricardo Haroun and Gercende Courtois de Viçose together with the ERA Chair Sachi Kaushik describe how the EcoAqua project has helped to strengthen the University of Las Palmas de Gran Canaria (ULPGC) and develop a centre of excellence for networking and research into sustainable marine aquaculture in the EU's outermost regions Impact Objectives • Foster research excellence in sustainable aquaculture under an ecosystem approach • Develop and strengthen the research potential and capacities of the University of Las Palmas de Gran Canaria (ULPGC) Fostering expertise in sustainable aquaculture The EcoAqua project was launched in June 2014. What do you consider to be its major achievements in the past two years? RH: EcoAqua is part of the ERA (European Research Area) Chairs initiative. Hiring a top international scientist as ERA Chair to guide and lead the development of the EcoAqua project objectives was the first action. Research lines in sustainable aquaculture and marine conservation topics have been reinforced with the arrival of five young scientists with expertise in different aspects of an ecosystem approach, such as integrated multi-trophic aquaculture, marine conservation, maritime spatial planning, genetic selection and fish nutrition. Another major achievement was to combine four different research groups of ULPGC into a more capable and efficient University Research Institute in Sustainable Aquaculture and Marine Ecosystems (IU-ECOAQUA). This is a major milestone and forms a stable research centre within ULPGC, with increased international visibility and autonomous potential for undertaking research and seeking funding. IU-ECOAQUA is developing a Strategic Plan of Sustainability with the advice of the ERA Chair in order to secure its future.

Marine Biotechnology, 2021

The phylum Mollusca represents one of the largest groups of marine invertebrates. Nowadays, mollu... more The phylum Mollusca represents one of the largest groups of marine invertebrates. Nowadays, molluscan shellfish belonging to the classes Bivalvia and Gastropoda are of commercial interest for fisheries and aquaculture. Although bioactive properties of bivalve molluscs have been widely investigated and several dietary supplements have been brought to the market, the bioactive potentialities of marine gastropods are poorly documented. The present study investigated the bioactive properties of tissue extracts derived from Haliotis tuberculata coccinea, or "European abalone," an edible abalone species distributed in the Mediterranean Sea and the northeast Atlantic Ocean. A bioactive organic compound-rich extract was obtained using ethyl acetate as extracting solvent. It showed antimicrobial activity towards the methicillin-resistant Staphylococcus epidermidis strain RP62A, the emerging multi-drug-resistant Stenotrophomonas maltophilia D71 and Staphylococcus aureus ATCC 6538P, being the most sensitive strain. It also showed anthelmintic activity, evaluated through the toxicity against the target model helminth Caenorhabditis elegans. In addition, the ethyl acetate extract demonstrated a selective cytotoxic activity on the cancer cell lines A375, MBA-MD 231, HeLa, and MCF7, at the concentration of 250 µg/mL. The fatty acid composition of the bioactive extract was also investigated through FAME analysis. The fatty acid profile showed 45% of saturated fatty acids (SAFA), 22% of monounsaturated fatty acids (MUFA), and 33% of polyunsaturated fatty acids (PUFA). The presence of some biologically important secondary metabolites in the extract was also analysed, revealing the presence of alkaloids, terpenes, and flavonoids.

Aquaculture reports, 2021

Hatchery production is critical to the successful aquaculture of a species. This study describes ... more Hatchery production is critical to the successful aquaculture of a species. This study describes the first captive breeding and reports on the embryonic development and early larval stages of the sea cucumber Holothuria sanctori, a species native to the Mediterranean and eastern Atlantic. Various induction methods were applied to obtain spawning in adult H. sanctori specimens; gametes were obtained from a spontaneous spawning event and from broodstock induced by mechanical shock coupled with algal stimulation. Fertilized eggs were then cultured at two different densities (0.3 egg/ml and 1 egg/ml) and fed two microalgae densities (5 × 10 3-2 × 10 4 cells/ml and 1 × 10 4-4 × 10 4 cells/ml) from the microalgae Nannochloropsis sp. and Amphora sp. and larval growth was recorded. Embryonic and larval development of H. sanctori were monitored on a daily basis for one month and auricularia larval growth was registered at days 5, 10, 15, and 20 after fertilization. The embryonic and larval stages were observed up to the late auricularia stage (14 days after fertilization). The best larval growth was observed at the lower egg and algal densities.

Frontiers in Marine Science, 2022

The production of cultured limpets is a recent research field contributing to aquaculture diversi... more The production of cultured limpets is a recent research field contributing to aquaculture diversification, focusing on low trophic species while reducing the carbon footprint.
Limpets are gastropods that colonize rocky substrates and are mostly present on tidal and subtidal shores. This animal group is in high commercial demand and is endangered in several regions. The aquaculture production of limpets has been traditionally challenging. The most successful reproduction method has been gonadal dissection,
as artificial spawning induction has shown limited success to date. Moreover, methods for larval culture, settlement, and juvenile growth have been poorly developed and remain largely unknown. In recent years, advances in this field have led to the optimization of methods to enhance larval production, larval culture, settlement induction of competent
larvae, and management of post-larvae and juveniles. The present manuscript reviews these advances, obtained within the framework of AQUAINVERT project, focusing on broodstock management, gametes release, larval production, larviculture, settlement, and grow-out of post-larvae, and providing an update on the actual state of the art in
limpets’ aquaculture.

Journal of Shellfish Research, 2010

The efficacy of clove oil as an anesthetic was evaluated in adult Haliotis tuberculata coccinea (... more The efficacy of clove oil as an anesthetic was evaluated in adult Haliotis tuberculata coccinea (shell length, 42–80 mm) and was compared with the commonly used 2-phemoxyethanol. The clove oil was previously mixed at 50% with absolute ethanol, and 4 different concentrations were tested: 0.1, 0.3, 0.5, and 0.7 mL/L. The trial was replicated 3 times. Relaxation and recovery time, muscle condition, and mortality after 1 wk were considered to evaluate the efficiency of anesthetics. The results showed that clove oil at 0.5 mL/L was the lowest concentration that removed all abalone from the rearing shelters in 8.9 ± 3.5 min, showing 2 ± 1.5 min of recovery time. Although clove oil is appropriate for handling animals, it was not suitable for pearl culture because it left the abalone muscle hard, making access to the pearl nuclei insertion site difficult. In comparison with 2-phenoxyethanol, clove oil was effective in 10-fold lower doses.

Aquaculture Nutrition, 2023

A 12-day experiment was conducted to investigate the effects of Artemia enrichment with two exper... more A 12-day experiment was conducted to investigate the effects of Artemia enrichment with two experimental microalgal emulsions
(formulated with selected fatty acid contents) on Penaeus vannamei postlarvae. For this purpose, 405,000 postlarvae (stage 1) were
obtained from a commercial hatchery in Santa Elena, Ecuador, and distributed into nine fiberglass tanks. Postlarvae were fed for
12 days with three experimental diets (three tanks per treatment): treatment A (Artemia enriched with experimental microalgal
emulsion A and dry diet), treatment B (Artemia enriched with experimental microalgal emulsion B and dry diet) and
nonenriched Artemia (Artemia without enrichment and dry diet). At the end of the experiment, length (mm), coefficient of
variation of population sizes, number of postlarvae in a gram of weight (PL-gram), biochemical composition, fatty acid profile,
hepatopancreas perimeter, and histopathological hepatopancreas status of P. vannamei postlarvae (stage 12) were analyzed. To
evaluate the status of the hepatopancreas, a categorization range (1–5) was created with different histological parameters such
as number of B cells, vesicles around them, healthy tubules, and degradation tissues. Growth traits did not present differences
between treatments; total length was 10.17 mm, 10.83 mm, and 10.27mm for treatment A, treatment B, and nonenriched
treatment, respectively, and PL-gram was 141.00, 162.00, and 142.33 for treatment A, treatment B, and nonenriched treatment,
respectively. Biochemical composition of postlarvae (lipids, ash, and protein content) did not present differences between the
three treatments. Significant differences were observed in the content of three essential fatty acids (DHA, DPA, and ARA) in
Penaeus vannamei postlarvae fed with Artemia enriched with experimental emulsions. Thus, DHA content was significantly
superior in animals fed with Artemia enriched with treatments A and B (9:80 ± 0:71%and 9:75 ± 0:44%, respectively) than in
animals fed with unenriched Artemia (5:78 ± 0:68) (P < 0:05). Concerning arachidonic acid (ARA), treatments A and B
showed 3:31 ± 0:20% and 3:19 ± 0:09%, respectively, higher than postlarvae fed with unenriched Artemia, 2:73 ± 0:04%
(P < 0:05). Regarding DPA content, treatments A and B reported higher values of MA and MB (0:81 ± 0:06% and 0:86 ± 0:08
%, respectively), than unenriched Artemia (0:43 ± 0:02%) (P < 0:05). Interestingly, the increase in DHA, DPA, and ARA
contents in postlarvae coincided with the increase in hepatopancreas perimeter. In addition, a large number of B cells, a large
number of healthy tubules, increased dilatation of the central tube, and a lower percentage of deteriorated tissue were observed
in the hepatopancreas when postlarvae were fed with enriched Artemia.

Journal of shellfish Research, 2010

Settlement and metamorphosis of Haliotis tuberculata coccinea larvae were examined in the presenc... more Settlement and metamorphosis of Haliotis tuberculata coccinea larvae were examined in the presence of different settlement cues reported effective in larval settlement of other abalone species (crustose coralline algae (CCA), Ulvella lens, conspecific mucus, γ-aminobutyric acid (GABA), and four benthic diatom species). In addition, larval density effect was tested on crustose coralline algae substrate. Larval settlement was highest on CCA followed by U. lens. Settlement was very low on conspecific mucus and γ-aminobutyric acid, varying between 1% and 2%. U. lens inoculated with the diatom Navicula incerta induced a reduced settlement of 9% compared to the 22% obtained on films of U. lens alone. The settlement induction efficiency of all the benthic diatoms tested (Amphora sp., N. incerta, Proschkinia sp. and Nitzschia sp.) was very low and not significantly different among diatom species. Larval settlement at 48h post-addition and survival after one month were higher for the lower larval density, whereas post-larval growth rates were not influenced by larval density.

Journal of Shellfish Research, 2010

This work reviews h e yield, biofiltering efficiencies and nutritional composition of Gracilaria ... more This work reviews h e yield, biofiltering efficiencies and nutritional composition of Gracilaria cornea J. Agardh and Ulva rigida C. Agardh cultivated with marine fish waste waters. Growth rate and total production reached values of 10.24 2.52 %d'l and 70.04 * 24.68g DW m" d" for U. rigida and 5.08 * 2.01 %d.' and 43.74 * 19.43 g DW m-' d.' for C. cornea. The ammonia removal eniciencies were 74% and 6 1% for U. rigida and C. cornea repectively. The suitability of the seaweed produced as a feed for abalone is discussed in tenns of protein, lipid and carbohydrate wntent.

Aquaculture, 2015

ABSTRACT

Journal of Shellfish Research, 2012

Aquaculture Nutrition

A 12-day experiment was conducted to investigate the effects of Artemia enrichment with two exper... more A 12-day experiment was conducted to investigate the effects of Artemia enrichment with two experimental microalgal emulsions (formulated with selected fatty acid contents) on Penaeus vannamei postlarvae. For this purpose, 405,000 postlarvae (stage 1) were obtained from a commercial hatchery in Santa Elena, Ecuador, and distributed into nine fiberglass tanks. Postlarvae were fed for 12 days with three experimental diets (three tanks per treatment): treatment A (Artemia enriched with experimental microalgal emulsion A and dry diet), treatment B (Artemia enriched with experimental microalgal emulsion B and dry diet) and nonenriched Artemia (Artemia without enrichment and dry diet). At the end of the experiment, length (mm), coefficient of variation of population sizes, number of postlarvae in a gram of weight (PL-gram), biochemical composition, fatty acid profile, hepatopancreas perimeter, and histopathological hepatopancreas status of P. vannamei postlarvae (stage 12) were analyzed. ...

Frontiers in Marine Science

The production of cultured limpets is a recent research field contributing to aquaculture diversi... more The production of cultured limpets is a recent research field contributing to aquaculture diversification, focusing on low trophic species while reducing the carbon footprint. Limpets are gastropods that colonize rocky substrates and are mostly present on tidal and subtidal shores. This animal group is in high commercial demand and is endangered in several regions. The aquaculture production of limpets has been traditionally challenging. The most successful reproduction method has been gonadal dissection, as artificial spawning induction has shown limited success to date. Moreover, methods for larval culture, settlement, and juvenile growth have been poorly developed and remain largely unknown. In recent years, advances in this field have led to the optimization of methods to enhance larval production, larval culture, settlement induction of competent larvae, and management of post-larvae and juveniles. The present manuscript reviews these advances, obtained within the framework of ...

Aquaculture Reports, 2021

Hatchery production is critical to the successful aquaculture of a species. This study describes ... more Hatchery production is critical to the successful aquaculture of a species. This study describes the first captive breeding and reports on the embryonic development and early larval stages of the sea cucumber Holothuria sanctori, a species native to the Mediterranean and eastern Atlantic. Various induction methods were applied to obtain spawning in adult H. sanctori specimens; gametes were obtained from a spontaneous spawning event and from broodstock induced by mechanical shock coupled with algal stimulation. Fertilized eggs were then cultured at two different densities (0.3 egg/ml and 1 egg/ml) and fed two microalgae densities (5 × 10 3-2 × 10 4 cells/ml and 1 × 10 4-4 × 10 4 cells/ml) from the microalgae Nannochloropsis sp. and Amphora sp. and larval growth was recorded. Embryonic and larval development of H. sanctori were monitored on a daily basis for one month and auricularia larval growth was registered at days 5, 10, 15, and 20 after fertilization. The embryonic and larval stages were observed up to the late auricularia stage (14 days after fertilization). The best larval growth was observed at the lower egg and algal densities.

Aquaculture International, 2012

Marine Biotechnology, 2021

The phylum Mollusca represents one of the largest groups of marine invertebrates. Nowadays, mollu... more The phylum Mollusca represents one of the largest groups of marine invertebrates. Nowadays, molluscan shellfish belonging to the classes Bivalvia and Gastropoda are of commercial interest for fisheries and aquaculture. Although bioactive properties of bivalve molluscs have been widely investigated and several dietary supplements have been brought to the market, the bioactive potentialities of marine gastropods are poorly documented. The present study investigated the bioactive properties of tissue extracts derived from Haliotis tuberculata coccinea, or "European abalone," an edible abalone species distributed in the Mediterranean Sea and the northeast Atlantic Ocean. A bioactive organic compound-rich extract was obtained using ethyl acetate as extracting solvent. It showed antimicrobial activity towards the methicillin-resistant Staphylococcus epidermidis strain RP62A, the emerging multi-drug-resistant Stenotrophomonas maltophilia D71 and Staphylococcus aureus ATCC 6538P, being the most sensitive strain. It also showed anthelmintic activity, evaluated through the toxicity against the target model helminth Caenorhabditis elegans. In addition, the ethyl acetate extract demonstrated a selective cytotoxic activity on the cancer cell lines A375, MBA-MD 231, HeLa, and MCF7, at the concentration of 250 µg/mL. The fatty acid composition of the bioactive extract was also investigated through FAME analysis. The fatty acid profile showed 45% of saturated fatty acids (SAFA), 22% of monounsaturated fatty acids (MUFA), and 33% of polyunsaturated fatty acids (PUFA). The presence of some biologically important secondary metabolites in the extract was also analysed, revealing the presence of alkaloids, terpenes, and flavonoids.

Phuket Marine Biological Center Special Publication 20, 1999

Singapore waters are heavily loaded with sediments, caused mainly by three decades of land reclam... more Singapore waters are heavily loaded with sediments, caused mainly by three decades of land reclamation and constant dredging for harbor and navigational purposes. Although all domestic sewage from mainland Singapore is treated, the waters also contain relatively high levels of nutrients, possibly due to heavy shipping activities, and other anthropogenic sources from the Johore and Malacca Straits. Ammonium and phosphate concentrations have been found to be 15 and 8 times higher, respectively, compared to levels at the Great Barrier Reef. The high sedimentation and nutrient levels have had a major effect on marine life in Singapore, especially coral reefs. Recent surveys made around the southern islands of Singapore recorded very few giant clams, compared to observations made two decades ago. Apart from the environmental issues, the unmanaged collection in the past also led to the serious decline of the giant clam population today. Consequently, one of the aims of the Tropical Marine Science Initiative of the National University of Singapore, is a reseeding of the reefs in Singapore's Marine Nature Areas.
The rehabilitation of giant clams in Singapore will be launched with the following aim:
a. Breed Tridacna squamosa, Tcrocea, Tmaxima and Hippopus hippopus in enriched waters;
b. Study the settlement stage of giant clam larvae;
c. Study the effects of nutrients on the early stages of clams such as the effects on survival at metamorphosis and settlement stages (the most critical phases) and the effects on growth of juveniles;
d. Observe animal physiology under high nutrients and sedimentation rates such as the observation of clearance and filtration rates in waters with high sedimentation rates and the observation of photosynthetic and filter feeding processes under high nutrient levels; and
e. Observe major stress signals due to water quality criteria.

Aquaculture international, 2013

The effect of egg density on embryonic development and larval quality as well as the lipid and fa... more The effect of egg density on embryonic development and larval quality as well as the lipid and fatty acid contents (eicosapentaenoic acid, EPA; docosahexaenoic acid, DHA) of cultured microalgae fed to Perna perna larvae was studied under controlled conditions to provide information needed for development of an experimental hatchery. Embryonic development followed the common sequence exhibited by other bivalves. D-larva stage was attained 40-44 h post-fertilisation at 21 ± 1°C. The umbo-stage was reached in 11 days, and pediveliger larvae were observed 26 days post-fertilisation. Low egg density (range 20-100 eggs cm-2) produced high proportions of normal D-larvae. Larval development showed two growth phases: 1st-the mixotrophic stage and 2nd-the exotrophic stage where the composition of diets had significant effects on larval growth with higher rates in larvae fed with the mixed microalgae (Isochrysis galbana ? Chaetoceros calcitrans, I. galbana ? Phaeodactylum tricornutum and I. galbana ? Skeletonema costatum) in comparison with the monospecific diet (I. galbana). Fatty acid analysis showed that larval growth and survival were strongly influenced by proportions of dietary DHA and EPA. These results indicate that DHA and EPA are the key factors in determining larval performance, considerably more than the total amount of other fatty acids.

Impact, 2017

Researchers Ricardo Haroun and Gercende Courtois de Viçose together with the ERA Chair Sachi Kaus... more Researchers Ricardo Haroun and Gercende Courtois de Viçose together with the ERA Chair Sachi Kaushik describe how the EcoAqua project has helped to strengthen the University of Las Palmas de Gran Canaria (ULPGC) and develop a centre of excellence for networking and research into sustainable marine aquaculture in the EU's outermost regions Impact Objectives • Foster research excellence in sustainable aquaculture under an ecosystem approach • Develop and strengthen the research potential and capacities of the University of Las Palmas de Gran Canaria (ULPGC) Fostering expertise in sustainable aquaculture The EcoAqua project was launched in June 2014. What do you consider to be its major achievements in the past two years? RH: EcoAqua is part of the ERA (European Research Area) Chairs initiative. Hiring a top international scientist as ERA Chair to guide and lead the development of the EcoAqua project objectives was the first action. Research lines in sustainable aquaculture and marine conservation topics have been reinforced with the arrival of five young scientists with expertise in different aspects of an ecosystem approach, such as integrated multi-trophic aquaculture, marine conservation, maritime spatial planning, genetic selection and fish nutrition. Another major achievement was to combine four different research groups of ULPGC into a more capable and efficient University Research Institute in Sustainable Aquaculture and Marine Ecosystems (IU-ECOAQUA). This is a major milestone and forms a stable research centre within ULPGC, with increased international visibility and autonomous potential for undertaking research and seeking funding. IU-ECOAQUA is developing a Strategic Plan of Sustainability with the advice of the ERA Chair in order to secure its future.

Marine Biotechnology, 2021

The phylum Mollusca represents one of the largest groups of marine invertebrates. Nowadays, mollu... more The phylum Mollusca represents one of the largest groups of marine invertebrates. Nowadays, molluscan shellfish belonging to the classes Bivalvia and Gastropoda are of commercial interest for fisheries and aquaculture. Although bioactive properties of bivalve molluscs have been widely investigated and several dietary supplements have been brought to the market, the bioactive potentialities of marine gastropods are poorly documented. The present study investigated the bioactive properties of tissue extracts derived from Haliotis tuberculata coccinea, or "European abalone," an edible abalone species distributed in the Mediterranean Sea and the northeast Atlantic Ocean. A bioactive organic compound-rich extract was obtained using ethyl acetate as extracting solvent. It showed antimicrobial activity towards the methicillin-resistant Staphylococcus epidermidis strain RP62A, the emerging multi-drug-resistant Stenotrophomonas maltophilia D71 and Staphylococcus aureus ATCC 6538P, being the most sensitive strain. It also showed anthelmintic activity, evaluated through the toxicity against the target model helminth Caenorhabditis elegans. In addition, the ethyl acetate extract demonstrated a selective cytotoxic activity on the cancer cell lines A375, MBA-MD 231, HeLa, and MCF7, at the concentration of 250 µg/mL. The fatty acid composition of the bioactive extract was also investigated through FAME analysis. The fatty acid profile showed 45% of saturated fatty acids (SAFA), 22% of monounsaturated fatty acids (MUFA), and 33% of polyunsaturated fatty acids (PUFA). The presence of some biologically important secondary metabolites in the extract was also analysed, revealing the presence of alkaloids, terpenes, and flavonoids.

Aquaculture reports, 2021

Hatchery production is critical to the successful aquaculture of a species. This study describes ... more Hatchery production is critical to the successful aquaculture of a species. This study describes the first captive breeding and reports on the embryonic development and early larval stages of the sea cucumber Holothuria sanctori, a species native to the Mediterranean and eastern Atlantic. Various induction methods were applied to obtain spawning in adult H. sanctori specimens; gametes were obtained from a spontaneous spawning event and from broodstock induced by mechanical shock coupled with algal stimulation. Fertilized eggs were then cultured at two different densities (0.3 egg/ml and 1 egg/ml) and fed two microalgae densities (5 × 10 3-2 × 10 4 cells/ml and 1 × 10 4-4 × 10 4 cells/ml) from the microalgae Nannochloropsis sp. and Amphora sp. and larval growth was recorded. Embryonic and larval development of H. sanctori were monitored on a daily basis for one month and auricularia larval growth was registered at days 5, 10, 15, and 20 after fertilization. The embryonic and larval stages were observed up to the late auricularia stage (14 days after fertilization). The best larval growth was observed at the lower egg and algal densities.

Frontiers in Marine Science, 2022

The production of cultured limpets is a recent research field contributing to aquaculture diversi... more The production of cultured limpets is a recent research field contributing to aquaculture diversification, focusing on low trophic species while reducing the carbon footprint.
Limpets are gastropods that colonize rocky substrates and are mostly present on tidal and subtidal shores. This animal group is in high commercial demand and is endangered in several regions. The aquaculture production of limpets has been traditionally challenging. The most successful reproduction method has been gonadal dissection,
as artificial spawning induction has shown limited success to date. Moreover, methods for larval culture, settlement, and juvenile growth have been poorly developed and remain largely unknown. In recent years, advances in this field have led to the optimization of methods to enhance larval production, larval culture, settlement induction of competent
larvae, and management of post-larvae and juveniles. The present manuscript reviews these advances, obtained within the framework of AQUAINVERT project, focusing on broodstock management, gametes release, larval production, larviculture, settlement, and grow-out of post-larvae, and providing an update on the actual state of the art in
limpets’ aquaculture.

Journal of Shellfish Research, 2010

The efficacy of clove oil as an anesthetic was evaluated in adult Haliotis tuberculata coccinea (... more The efficacy of clove oil as an anesthetic was evaluated in adult Haliotis tuberculata coccinea (shell length, 42–80 mm) and was compared with the commonly used 2-phemoxyethanol. The clove oil was previously mixed at 50% with absolute ethanol, and 4 different concentrations were tested: 0.1, 0.3, 0.5, and 0.7 mL/L. The trial was replicated 3 times. Relaxation and recovery time, muscle condition, and mortality after 1 wk were considered to evaluate the efficiency of anesthetics. The results showed that clove oil at 0.5 mL/L was the lowest concentration that removed all abalone from the rearing shelters in 8.9 ± 3.5 min, showing 2 ± 1.5 min of recovery time. Although clove oil is appropriate for handling animals, it was not suitable for pearl culture because it left the abalone muscle hard, making access to the pearl nuclei insertion site difficult. In comparison with 2-phenoxyethanol, clove oil was effective in 10-fold lower doses.

Aquaculture Nutrition, 2023

A 12-day experiment was conducted to investigate the effects of Artemia enrichment with two exper... more A 12-day experiment was conducted to investigate the effects of Artemia enrichment with two experimental microalgal emulsions
(formulated with selected fatty acid contents) on Penaeus vannamei postlarvae. For this purpose, 405,000 postlarvae (stage 1) were
obtained from a commercial hatchery in Santa Elena, Ecuador, and distributed into nine fiberglass tanks. Postlarvae were fed for
12 days with three experimental diets (three tanks per treatment): treatment A (Artemia enriched with experimental microalgal
emulsion A and dry diet), treatment B (Artemia enriched with experimental microalgal emulsion B and dry diet) and
nonenriched Artemia (Artemia without enrichment and dry diet). At the end of the experiment, length (mm), coefficient of
variation of population sizes, number of postlarvae in a gram of weight (PL-gram), biochemical composition, fatty acid profile,
hepatopancreas perimeter, and histopathological hepatopancreas status of P. vannamei postlarvae (stage 12) were analyzed. To
evaluate the status of the hepatopancreas, a categorization range (1–5) was created with different histological parameters such
as number of B cells, vesicles around them, healthy tubules, and degradation tissues. Growth traits did not present differences
between treatments; total length was 10.17 mm, 10.83 mm, and 10.27mm for treatment A, treatment B, and nonenriched
treatment, respectively, and PL-gram was 141.00, 162.00, and 142.33 for treatment A, treatment B, and nonenriched treatment,
respectively. Biochemical composition of postlarvae (lipids, ash, and protein content) did not present differences between the
three treatments. Significant differences were observed in the content of three essential fatty acids (DHA, DPA, and ARA) in
Penaeus vannamei postlarvae fed with Artemia enriched with experimental emulsions. Thus, DHA content was significantly
superior in animals fed with Artemia enriched with treatments A and B (9:80 ± 0:71%and 9:75 ± 0:44%, respectively) than in
animals fed with unenriched Artemia (5:78 ± 0:68) (P < 0:05). Concerning arachidonic acid (ARA), treatments A and B
showed 3:31 ± 0:20% and 3:19 ± 0:09%, respectively, higher than postlarvae fed with unenriched Artemia, 2:73 ± 0:04%
(P < 0:05). Regarding DPA content, treatments A and B reported higher values of MA and MB (0:81 ± 0:06% and 0:86 ± 0:08
%, respectively), than unenriched Artemia (0:43 ± 0:02%) (P < 0:05). Interestingly, the increase in DHA, DPA, and ARA
contents in postlarvae coincided with the increase in hepatopancreas perimeter. In addition, a large number of B cells, a large
number of healthy tubules, increased dilatation of the central tube, and a lower percentage of deteriorated tissue were observed
in the hepatopancreas when postlarvae were fed with enriched Artemia.

Journal of shellfish Research, 2010

Settlement and metamorphosis of Haliotis tuberculata coccinea larvae were examined in the presenc... more Settlement and metamorphosis of Haliotis tuberculata coccinea larvae were examined in the presence of different settlement cues reported effective in larval settlement of other abalone species (crustose coralline algae (CCA), Ulvella lens, conspecific mucus, γ-aminobutyric acid (GABA), and four benthic diatom species). In addition, larval density effect was tested on crustose coralline algae substrate. Larval settlement was highest on CCA followed by U. lens. Settlement was very low on conspecific mucus and γ-aminobutyric acid, varying between 1% and 2%. U. lens inoculated with the diatom Navicula incerta induced a reduced settlement of 9% compared to the 22% obtained on films of U. lens alone. The settlement induction efficiency of all the benthic diatoms tested (Amphora sp., N. incerta, Proschkinia sp. and Nitzschia sp.) was very low and not significantly different among diatom species. Larval settlement at 48h post-addition and survival after one month were higher for the lower larval density, whereas post-larval growth rates were not influenced by larval density.

Journal of Shellfish Research, 2010

This work reviews h e yield, biofiltering efficiencies and nutritional composition of Gracilaria ... more This work reviews h e yield, biofiltering efficiencies and nutritional composition of Gracilaria cornea J. Agardh and Ulva rigida C. Agardh cultivated with marine fish waste waters. Growth rate and total production reached values of 10.24 2.52 %d'l and 70.04 * 24.68g DW m" d" for U. rigida and 5.08 * 2.01 %d.' and 43.74 * 19.43 g DW m-' d.' for C. cornea. The ammonia removal eniciencies were 74% and 6 1% for U. rigida and C. cornea repectively. The suitability of the seaweed produced as a feed for abalone is discussed in tenns of protein, lipid and carbohydrate wntent.

Aquaculture, 2015

ABSTRACT

Journal of Shellfish Research, 2012