Percorrer por autor "Ferreira, Susana M. F."
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- Can artificial diets be a feasible alternative for the gonadal growth and maturation of the sea urchin Paracentrotus lividus (Lamarck, 1816)?Publication . Santos, Pedro M.; Ferreira, Susana M. F.; Albano, Pedro; Raposo, Andreia; Costa, José L.; Pombo, AnaParacentrotus lividus (Lamarck 1816) has high-value reddishorange gonads that are regarded as a delicacy. In this study, three jellified diets have been tested for 90 days to assess the effect of different diets on P. lividus somatic and gonadal growth, gonad color, and reproductive state. All diets contained agar as a gelling agent and consisted of: maize and spinach (A); maize, spinach, and macroalga Laminaria digitata (B); and maize, spinach, and pumpkin Cucurbita maxima (C). Diet B was the most successful in promoting somatic growth with regard to test diameter (1.2 mm month−1) and total wet weight (79.9 mg ind−1 day−1). The individuals from Diet A presented a higher final gonadosomatic index (9.07 ± 2.39%) where all sea urchins initially presented with an index of 3.33 ± 0.02%. Diets A and C led to a marked advance (p < .05) in the gametogenic cycle (66.7% and 46.7% of the individuals with mature gametes, respectively), while Diet B resulted in less-developed gonadal stages, which are more appropriate for commercial purposes in terms of sensorial characteristics appreciated by the consumers. The gonad color analyses confirmed a redder roe in females and also the suitability of C. maxima as a potential gonad color enhancer for P. lividus.
- Effect of three diets on the gametogenic development and fatty acid profile of Paracentrotus lividus (Lamarck, 1816) gonadsPublication . Raposo, Andreia I.G.; Ferreira, Susana M. F.; Ramos, Rodolfo; Santos, Pedro M.; Anjos, Catarina; Baptista, Teresa; Tecelão, Carla; Costa, José L.; Pombo, AnaIn this study, the effects of three diets were investigated to enhance Paracentrotus lividus production for commercial purposes. P. lividus were fed ad libitum for 80 days with: diet A—fresh Codium tomentosum Stackhouse, 1797; diet B—formulated using a jellified mix of macroalgae and vegetables, including C. tomentosum (20%), Coralina sp. Linnaeus, 1758 (17%), cabbage Brassica oleracea var. capitata Linnaeus, 1753 (30%), carrot Daucus carota Linnaeus, 1753 (30%) and agar (3%) as a gelling agent. Diet C consisted of maize Zea mays Linnaeus, 1753 (56%) and New Zealand spinach Tetragonia tetragonoides (Pallas, 1781) Kuntze, 1891 (44%). Their effects on the gonadal and somatic growths, gonadosomatic index (GI) and gametogenesis were evaluated, as well as on the total lipid content and fatty acid composition of sea urchin's gonads. Diet A provided high values of eicosapentaenoic acid (EPA). Gonads of sea urchins fed with diet A were found mostly in growth and maturation stages of ametogenesis and showed the lowest lipid content. Sea urchins fed with diet B presented their gonads in the reabsorption stage and had the highest values of omega‐3 polyunsaturated fatty acids (PUFAs). Sea urchins fed with diet C were in the early stages of gametogenesis and had the highest values of lipid content, plus omega‐6 PUFAs. Once as an ingredient in a balanced mix with vegetables, C. tomentosum can be a key factor to the development of new promising high‐quality and low‐cost feed for P. lividus roe enhancement.
- Effects of single and mixed-diatom diets on growth, condition, and survival of larvae of the sea urchin Paracentrotus lividus (Lamarck, 1816)Publication . Gomes, Ana; Lourenço, Sílvia; Santos, Pedro M.; Raposo, Andreia; Mendes, Susana; Gonçalves, Sílvia C.; Ferreira, Susana M. F.; Pombo, AnaThe development of rearing protocols promoting the larval development, pre and postmetamorphosis are key for echinoculture. Mixed diets combining diatom with other microalgae have been used with success and Rhodomonas sp. (Rho)-based diets showed promising results in larval survival. This study was aimed to evaluate the rearing success of Paracentrotus lividus larvae fed with mixed diets combining Rho with two diatoms, Phaedactylum tricornutum (Phae) and Chaetoceros calcitrans (Chae) in two experiments. In experiment I, the effect of the mixed diet of Rho and Phae (Mix I) was compared with monospecific diets of both species, while in experiment II, Rho was combined with Chae (Mix II) and compared with both monospecific diets. In experiment I, larvae fed with Rho I and Mix I diets grew faster than larvae fed with Phae I diet, attained the competence earlier with survival rates of 15-16%. In experiment II, the larvae fed with Rho were larger and the larvae fed with Mix II attained the highest survival rate (32.22%). The analysis of the larval biometric models showed that the larger larvae, with bigger stomachs, and shorter post-oral arm attained the age-at-competence earlier with higher survival rates. In conclusion, the larvae fed with a combination of Rho with the selected diatoms showed identical growth performance and condition to larvae fed with Rho monospecific diet but obtained higher survival rate. These results indicate that mixed-diatoms diets may be more suitable for P. lividus larval rearing.
- Homegreens - Aquaponics System as an Educational Tool towards a Sustainable FuturePublication . Carreira, Rute; Diz, Francisco; Pessanha, Luis; Bernardino, Raul; Franco, Inês M.; Mota, Alexandra; Faustino, Emanuel; Silva, Orlando R.; Ferreira, Susana M. F.Aquaponics is an integrated production practice that emerges from the combi-nation of two farming techniques: hydroponics and aquaculture. It consists in a simulation of a natural ecosystem that grows plants without soil substrate in the nutrient enriched waters recirculated from aquaculture systems. This type of production offers several advantages, namely economic and ecological ones. Homegreens is a project that aims to create small saltwater and freshwater aquaponic sys-tems, which can be installed in schools and serve as a didactic tool for introducing contents such as biology and sustainability to a juvenile audience. Implemented by a designers, biol-ogists and agronomists’ multidisciplinary team, the methodology was based on the develop-ment and quantitative validation of prototypes, and the installation and qualitative analyses of user’s interaction. These small scale aquaponic systems consists on a grow bed, an aquarium with a capacity for 45L, a protection barrier for the plant’s roots, aeration, biofilters and a thermostat. Sever-al simplified models were developed, presented and installed in two primary schools. Labor-atory tests were conducted to validate the use of a cork grow bed and a 3D printed polya-cid lactic (PLA) aeration and biofilter system. Children’s engagement and interaction with these simplified models, indicates that these systems will provide a biology and sustainability related group learning opportunity.
- Insight into aquaculture's potential of marine annelid worms and ecological concerns: a reviewPublication . Pombo, Ana; Baptista, Teresa; Granada, Luana; Ferreira, Susana M. F.; Gonçalves, Sílvia C.; Anjos, Catarina; Sá, Erica; Chainho, Paula; Fonseca, Luís Cancela da; Fidalgo e Costa, Pedro; Costa, José L.Polychaetes are marine annelid worms that can contribute to aquaculture diversification. Its culture has been viable, and commercially attempted, but intensive production has progressed only in few countries around the world. In the countries with no production, marine polychaetes are imported or harvested. A strong and sustained research investment provided to a better understanding of the nutritional requirements and reproduction of some species. Recent studies showed new technical improvements, which can lead to an important progress in productivity and give a new impetus to the polychaete production. Some marine worm species were identified as good candidates for integrated multitrophic aquaculture. The development of cost-effective aquaculture techniques for marine annelid worms is essential to ensure a balance between commercial interests and the preservation of ecosystems. The influence of polychaete aquaculture on the environment and vice versa raise important concerns related to ecological security and sustainability of this activity. This review focus on the main technical improvements and advances that have been made in areas as diverse as: aquaculture potential of polychaetes, reared species, main species used worldwide, and highlights biological and ecological concerns, important challenges and recommendations.
- Insight into aquaculture’s potential of marine annelid worms and ecological concerns: a reviewPublication . Pombo, Ana; Baptista, Teresa; Granada, Luana; Ferreira, Susana M. F.; Gonçalves, Sílvia C.; Anjos, Catarina; Sá, Erica; Chainho, Paula; Fonseca, Luís Cancela da; Costa, Pedro Fidalgo e; Costa, José L.Polychaetes are marine annelid worms that can contribute to aquaculture diversification. Its culture has been viable, and commercially attempted, but intensive production has progressed only in few countries around the world. In the countries with no production, marine polychaetes are imported or harvested. A strong and sustained research investment provided to a better understanding of the nutritional requirements and reproduction of some species. Recent studies showed new technical improvements, which can lead to an important progress in productivity and give a new impetus to the polychaete production. Some marine worm species were identified as good candidates for integrated multitrophic aquaculture. The development of cost-effective aquaculture techniques for marine annelid worms is essential to ensure a balance between commercial interests and the preservation of ecosystems. The influence of polychaete aquaculture on the environment and vice versa raise important concerns related to ecological security and sustainability of this activity. This review focus on the main technical improvements and advances that have been made in areas as diverse as: aquaculture potential of polychaetes, reared species, main species used worldwide, and highlights biological and ecological concerns, important challenges and recommendations.
- Is the plant Bolboschoenus maritimus an adequate biomonitor for trace metal contamination in saltmarshes? A field study from the Óbidos lagoon (Portugal)Publication . Santos, Márcia S.S.; Pedro, Carmen A.; Ferreira, Susana M. F.; Gonçalves, Sílvia C.Monitoring the negative impacts of trace metals is crucial to assess the health and stability of ecosystems. In salt marshes, halophyte plants were reported as possible bioaccumulators of these elements. The aim of this work was to explore the bioaccumulation potential of Bolboschoenus maritimus as a tool for monitoring the presence of metals in coastal environments. Bolboschoenus maritimus were collected from a brackish water lagoon, and the presence of the trace metals lead, cadmium, and nickel were seasonally evaluated in distinct parts of the plants, and in water and sediment samples. Lead was the trace metal with the highest concentration detected in water and sediments of the sampling site. The highest lead concentrations in B. maritimus were recorded in the spring season. The transport index indicated an accumulation of lead in the leaves of around 70% in the spring of 2009. Cadmium in leaves in spring and summer of 2009 reached values above 5 mg Cd. kg−1. Nickel was not detected in most samples collected. Bolboschoenus maritimus was considered an adequate biomonitor for lead and cadmium, since it bioaccumulates both metals with seasonally distinct results, as the bioaccumulation factor results indicated.
- Monitoring metal pollution on coastal lagoons using Cerastoderma edule: a report from a moderately impacted system in Western Portugal: Óbidos LagoonPublication . Veiga, Kelly; Pedro, Carmen A.; Ferreira, Susana M. F.; Gonçalves, Sílvia C.The main goal of this monitoring program was to evaluate the contamination in the intertidal environment of Óbidos Lagoon by the metals Cd, Pb, and Ni on water, sediments, and on biological samples, using the bivalve Cerastoderma edule (common name: cockle) as a biomonitor. Since C. edule is an edible mollusc, the risk of their consumption by humans from this lagoon was also evaluated. The study was performed in a restricted area of the lagoon—the MLstation—where human activities, such as shellfish harvesting, intersect with the natural processes occurring in this system. The results obtained revealed that the water samples were polluted with Cd and Pb with concentrations (0.00025 mg l−1 and 0.0072 mg l−1) above the maximum legislated on the Directive 2008/105/EC, while for Ni, this occurred only on one of the seasons sampled (summer 2010: 0.029 mg l−1). The sediments were not contaminated with Cd and Ni, and the contamination detected for the metal Pb, allowed the classification of this station as an unpolluted site ([Pbmin] = 7.477 mg.kg−1 and [Pbmax] = 19.875mg.kg−1). On biological samples, comparing the results of metal contaminations with the values of the maximum levels fixed by European Commission Regulation (EC) No 1881/2006 and USFDA, all the results were below the legal value. Therefore, during the period of study, the consumption of this bivalve by humans was safe. Also, BAF and CF calculations suggest that C. edule can be used as a biomonitor to determine the source of the contaminations. This study supported the use of C. edule as a biomonitor to assess the contamination by the metals Pb and Ni at the Óbidos Lagoon and allowed to predict the potential transfer of metals to higher trophic levels with potential impacts on the natural and human communities.
- Optimization of feeding quantity and frequency to rear the cyprinid fish Garra rufa: Heckel, 1843Publication . Catarino, Mafalda M. R. S.; Gomes, Mónica R. S.; Ferreira, Susana M. F.; Gonçalves, Sílvia C.Garra rufa has a high commercial value, but their rearing methods are still unknown. Aspects like an adequate daily dose and feeding frequency need to be investigated. This work aimed to establish the optimal feed dose per day to obtain satiation and the optimal frequency of feeding to rear a specific size class of G. rufa. A total of 60 fish were distributed by six aquaria containing 10 fish. First, the fish were fed twice per day, by providing a feed dose correspondent to 1% of their body weight and increasing 0.1 g/fish on the following days, until finding feed leftovers on the next morning. Afterwards, the fish went through a 1 month experimental trial to evaluate the optimal feeding frequency. Fish growth was compared between feeding the optimal daily dose distributed in two or three feeding moments per day. The optimal dose that ensured satiation was 0.042 g fish−1 day−1 (3.2% of fish’ body weight). Feeding the fish three times per day promoted higher growth rates, since the fish’ total length was statistically different between feeding frequencies. Statistically significant differences between feeding frequencies were not observed for growth performance parameters. These results contribute to the aquaculture of this target species, allowing fish industry to more efficiently respond to the high demand for G. rufa and, simultaneously, for its preservation in the wild.
- Principais Patógenos que Afetam Peixes Cultivados em PortugalPublication . Pires, Damiana; Vaz, Mariana; Pires, Pedro; Passos, Ricardo; Carmo, Beatriz; Santos, Paulo; Tomás, Mafalda; Ferreira, Susana M. F.; Baptista, TeresaA mortalidade de peixes que ocorre nas explorações aquícolas, devida à ação de agentes patogénicos, constitui ainda um dos maiores entraves ao desenvolvimento económico do sector. Tendo em conta a sua origem, as doenças podem subdividir-se em não infeciosas e infeciosas, sendo estas últimas as de maior importância e a principal causa de perdas económicas elevadas. As doenças infeciosas agrupam-se em três categorias, de acordo com a sua etiologia viral, bacteriana e parasítica. Estas doenças são muitas vezes indicadoras de condições fisiológicas e patológicas, resultantes de alimentação inadequada, infeções subclínicas, ou condições ambientais adversas. Quando simultaneamente existem condições favoráveis para a multiplicação do patógeno e condições adversas para os peixes, observa-se o desenvolvimento da doença. Entre as condições adversas que podem diminuir a resposta imune dos peixes cultivados, provocando uma maior predisposição aos patógenos, enumeram-se: densidade elevada, baixos níveis de oxigénio, stress alimentar, stress provocado pelo transporte, acumulação de compostos azotados, alterações de pH, entre outros. Estas situações, tendo em conta as consequências, merecem uma atenção redobrada por parte dos aquicultores.