Influência da dieta parental na qualidade lipídica dos ovos e no desenvolvimento embrionário de camarinha, Palaemonetes varians

Dissertação mest., Biologia Marinha, Universidade do Algarve, 2008A camarinha P. varians é um camarão eurihalino muito abundante em regiões estuarinas e de sapal, de características temperadas. É utilizado para consumo humano e para a pesca apresentando actualmente uma procura crescente. Neste trabalho pretende-se averiguar, de modo preliminar as exigências nutricionais em ácidos gordos e a viabilidade de cultivo. Utilizaram-se cinco dietas, D1 (Artemia), D2 (Coelho), D3 (S.One), D4 (Poliqueta), D5 (AquaS2) facilmente disponíveis e com diferentes perfis em ácidos gordos, tendo-se observado a sua aceitabilidade e o efeito na condição física e na reprodução dos camarões, investigou-se a influência das dietas parentais nas reservas lipídicas dos ovos e do embrião e como é efectuada a gestão dos ácidos gordos ao longo da embriogénese. Como comparação aos camarões cultivados, amostraram-se também camarões “selvagens” recolhidos na Ria Formosa. Verifica-se que esta espécie apresenta a capacidade de utilizar os ácidos gordos de forma selectiva, utilizando ácidos gordos não-essenciais e/ou abundantes como forma de energia, armazenando os ácidos gordos essenciais, parece também, demonstrar uma capacidade de biossíntese de HUFA superior a outros decápodes, o que associado à facilidade de cultivo e resistência ao maneio a tornam muito interessante para aquacultura. As dietas D4 (Poliqueta) e D5 (AquaS2) apresentaram os melhores resultados ao fim de 6 meses de ensaio

Sound production in the Meagre, Argyrosomus regius (Asso, 1801): intraspecific variability associated with size, sex and context

Many fish taxa produce sound in voluntary and in disturbance contexts but information on the full acoustic repertoire is lacking for most species. Yet, this knowledge is critical to enable monitoring fish populations in nature through acoustic monitoring.Portuguese Foundation for Science and Technology: PTDC/BIA-BMA/30517/2017; SFRH/BD/115562/2016; UID/MAR/04292/2019; UID/BIA/00329/2019; PTDC/BIA-BMA/29662/2017.info:eu-repo/semantics/publishedVersio

Impacts of ocean warming and acidification on the energy budget of three commercially important fish species

Funding This study was supported by the project FISHBUDGET -Effects of climate change on marine fish energy budgets (PTDC/BIA-BMA/28630/2017) from the Portuguese Foundation for Science and Technology (FCT). FCT also supported the contract of Patrícia Anacleto in the framework of the CEECIND 2017 (CEECIND/01739/2017). Acknowledgments This study benefited from the strategic project UIDB/04292/2020 awarded to MARE and through project LA/P/0069/2020 granted to the Associate Laboratory ARNET funded by the FCT/Ministério da Ciência, Tecnologia e Ensino Superior (MCTES), and through other national funds (UIDB/50006/2020). The authors thank the Sparos, Lda company for providing the fish feed, and Olhão Pilot Fish Farming Station team (EPPO-IPMA) for providing the juvenile fish for trials. Publisher Copyright: © 2022 The Author(s). Published by Oxford University Press and the Society for Experimental Biology.A mechanistic model based on Dynamic Energy Budget (DEB) theory was developed to predict the combined effects of ocean warming, acidification and decreased food availability on growth and reproduction of three commercially important marine fish species: white seabream (Diplodus sargus), zebra seabream (Diplodus cervinus) and Senegalese sole (Solea senegalensis). Model simulations used a parameter set for each species, estimated by the Add-my-Pet method using data from laboratory experiments complemented with bibliographic sources. An acidification stress factor was added as a modifier of the somatic maintenance costs and estimated for each species to quantify the effect of a decrease in pH from 8.0 to 7.4 (white seabream) or 7.7 (zebra seabream and Senegalese sole). The model was used to project total length of individuals along their usual lifespan and number of eggs produced by an adult individual within one year, under different climate change scenarios for the end of the 21st century. For the Intergovernmental Panel on Climate Change SSP5-8.5, ocean warming led to higher growth rates during the first years of development, as well as an increase of 32-34% in egg production, for the three species. Ocean acidification contributed to reduced growth for white seabream and Senegalese sole and a small increase for zebra seabream, as well as a decrease in egg production of 48-52% and 14-33% for white seabream and Senegalese sole, respectively, and an increase of 4-5% for zebra seabream. The combined effect of ocean warming and acidification is strongly dependent on the decrease of food availability, which leads to significant reduction in growth and egg production. This is the first study to assess the combined effects of ocean warming and acidification using DEB models on fish, therefore, further research is needed for a better understanding of these climate change-related effects among different taxonomic groups and species.publishersversionpublishe

Reduction of skeletal anomalies in meagre (Argyrosomus regius, Asso, 1801) through early introduction of inert diet

The consolidation of meagre (Argyrosomus regius) in aquaculture requires an understanding and optimization of larval rearing and nutritional conditions. The aim of this study was to analyse the effects of an early introduction of inert diets during larval rearing, on growth performance, digestive enzymes activity and development of skeletal anomalies. This study evaluated the effects of three different timings for the introduction of inert diet during larval rearing: a control group (CTRL) where inert diet was initiated at 14 days after hatching (DAH) and two treatment groups that had an earlier introduction of inert diet at 8 DAH (T1) and 11 DAH (T2). Meagre larvae exhibited similar pancreatic and intestinal enzymatic activities among the different dietary treatments. No differences in the overall prevalence of anomalies were observed between treatments at 25 or 50 DAH, however, a significant reduction was observed in all groups with the transition from larval to juvenile stage. The precocious introduction of inert diet shifted the distribution of vertebral anomalies to a more anterior vertebral column region. Altogether, this study shows that earlier introduction of inert diets in meagre hatcheries can be beneficial for meagre production in aquaculture.info:eu-repo/semantics/publishedVersio

Impact of anthropogenic noise on the survival and development of meagre (Argyrosomus regius) early life stages

The growth of human populations has been driving an unprecedent and widespread increase in marine traffic, posing a real threat to marine biodiversity. Even though we are now aware of the negative effects of shipping noise exposure on fish, information about the impact on their early life stages continues to lack. Meagre (Argyrosomus regius) is a vocal fish that uses estuaries with high levels of anthropogenic noise pollution as both breeding areas and nurseries. Here, the effects of boat noise exposure on the development and survival of meagre larvae were studied. Embryos and larvae were exposed to either noise (boat noise playback) or control treatments (coils producing a similar electric field to the speakers) and hatching rate, survival rate, morphometric traits and stress-related biomarkers, at hatching and at 2 days-post-hatching (dph) were analyzed. Results showed no conclusive effects of the impact of boat noise playback, even though there was an increased lipid droplet consumption and a decrease in body depth at 2dph larvae under this stressor. The assessment of oxidative stress and energy metabolism-related biomarkers at hatching showed a marginal decrease in superoxide dismutase (SOD) activity and no changes in DNA damage or electron transport system activity (ETS), although it cannot be disregarded that those effects could only be visible at later stages of larval development. Whether these morphological and developmental results have implications in later stages remains to be investigated. Further studies with longer exposure and wild meagre could help deepen this knowledge and provide a better understanding of how anthropogenic noise can impact meagre early stagesFundação para a Ciência e Tecnologia - FCTinfo:eu-repo/semantics/publishedVersio

Validación del Nursing Activities Score en unidades de cuidados intensivos portuguesas

Objective: to describe the process of adaptation and validation of the Nursing Activities Score to the Portuguese context. Method: this was a pilot study of adaptation and validation of the Nursing Activities Score with a sample consisting of 67 patients hospitalized in the intensive care units of three Portuguese hospitals. The construct validity was assessed through factor analysis procedures and the internal consistency of the items was measured through the Cronbach’s alpha coeffi cient. Results: a mean workload value of 63.04% (SD = 14.25; Median = 61.30) was obtained. Psychometric data revealed a Cronbach’s alpha of 0.71 in the total scale, indicating an acceptable accuracy. Confi rmatory factor analysis suggested an appropriate adjustment between the model and the data (χ2 (199) = 214.5, p = 0.214; CFI = 0.95; RMSA = 0.035). Conclusion: in the present study, the Portuguese version of the Nursing Activities Score was found to be a valid instrument, enabling a safe assessment of the workload of nurses.Objetivo: descrever o processo de adaptação e validação do Nursing Activities Score para o contexto português. Método: trata-se de um estudo-piloto de adaptação e validação do Nursing Activities Score, com amostra de 67 doentes internados em unidades de cuidados intensivos de três hospitais portugueses. A validade de constructo avaliou-se mediante procedimentos de análise fatorial e a consistência interna dos itens através do coefi ciente Alpha de Cronbach. Resultados: obteve-se um valor médio da carga de trabalho de 63,04% (DP = 14,25; Mediana = 61,30). Os dados psicométricos revelaram um Alpha de Cronbach de 0,71, na escala total, indicando uma fi delidade aceitável. A análise fatorial confi rmatória sugeriu um ajustamento adequado entre o modelo e os dados (χ2(199) = 214,5, p = 0,214; CFI = 0,95; RMSA = 0,035). Conclusão: neste estudo, a versão portuguesa do Nursing Activities Score revelou-se um instrumento válido, permitindo avaliar a carga de trabalho dos enfermeiros com segurançaObjetivo: describir el proceso de adaptación y validación del Nursing Activities Score al contexto portugués. Método: estudio piloto de adaptación y validación del Nursing Activities Score, con muestra de 67 pacientes internados en unidades de cuidados intensivos de tres hospitales portugueses. La validez del constructo se evaluó mediante análisis factorial y por consistencia interna de los ítems evaluados a través del coefi ciente Alpha de Cronbach. Resultados: se obtuvo un valor medio de carga de trabajo de 63,04% (SD=14,25; Mediana=61,30). Los datos psicométricos expresaron un Alpha de Cronbach de 0,71 en la escala total, indicando fi delidad aceptable. El análisis factorial confi rmatorio sugirió un ajuste adecuado entre el modelo y os datos (χ2 (199)=214,5; p=0,214; CFI=0,95; RMSA=0,035). Conclusión: en este estudio, la versión portuguesa del Nursing Activities Score demostró ser un instrumento válido, permitiendo evaluar la carga de trabajo de los enfermeros con precisión

Characterization of spawning rhythms of a sparidae aquaculture species, the white seabream (Diplodus sargus), in the south of Portugal

One of the most visible features of fish reproduction is seasonality; however, daily rhythmicity is present in most species and should not be disregarded. This study investigated the seasonal and daily spawning rhythms of the white seabream (Diplodus sargus) in captivity, and a possible endogenous control of the daily rhythm. Spawns were monitored daily, during an entire reproductive season by using an automatic and programmable egg collector. The spawning season lasted 5 months, from January until June, when temperatures oscillated between 11.5 and 24.4 degrees C. Female fecundity was higher between 17.5 and 20.4 degrees C, suggesting a temperature influence in spawning. This species showed a very clear daily spawning rhythm (Cosinor analysis, p < 0.001), strongly related with photoperiod. Eggs started to be released at sunset and peaked around 21:00 h. Egg quality parameters also changed along the spawning period, with viability and hatching rates, increasing towards the end of the night period. The spawning rhythm persisted (Cosinor analysis, p < 0.001) for 5 days under constant light conditions, suggesting the presence of an endogenous clock mechanism which controlled this circadian pattern. The present results represent an advantage for the optimization of egg production protocols in this species, and an added value to the current knowledge of marine fish physiology.info:eu-repo/semantics/publishedVersio

Scientific objects in the exhibition CHIMICA| the art of transforming matter

Secondary School André de Gouveia (ESAG) is frequently associated to Lyceu d’Évora from which it inherited the historical and cultural background. Lyceu d’Évora was established in 1841 after the educational reform of Passos Manuel and was set at Colégio do Espírito Santo, in Évora, until 1979. During that period, a physics and chemistry laboratory was created and developed at the Lyceu and it was enriched with brand new scientific objects and small equipment to be used in classes, especially in teaching demonstrations. Crosschecking the information from the records kept at the library of ESAG, sales catalogues and teaching books from that period and information from other sources, it was possible to find out, in several cases, who the seller or the manufacturer of the object was and its function in an experimental design at the laboratory. Analytical scales, Mohr-Westphal balance, gasometers, pneumatic machine or alembic are some of the objects that are analysed from a real and historical point of view. Part of this collection is currently in exhibition in Évora Museum under the name of CHIMICA | the art of transforming matter. Chemistry depends on working with material things and processes and a chemistry laboratory is, in fact, a prototype of a large-scale industry through the synthesis of chemical compounds and the interaction with technological processes

Are Microplastics Impairing Marine Fish Larviculture?—Preliminary Results with Argyrosomus regius

The presence of small-sized (&lt;300 &micro;m) microplastics (MPs) in aquaculture facilities may threaten finfish hatchery, as their (in)voluntary ingestion by fish larvae may compromise nutritional requirements during early ontogeny, and consequently larval health and performance. Thus, we addressed the short-term effects (7 h) of polyethylene microplastics (0.1, 1.0, 10 mg/L, PE-MPs) in meagre larvae Argyrosomus regius (15 dph) in the presence/absence of food. Larval feeding behavior, oxidative stress status, neurotoxicity, and metabolic requirements were evaluated. Results showed that meagre larvae ingested PE-MPs regardless of their concentration, decreasing in the presence of food (Artemia metanauplii). The presence of PE-MPs compromised larval feeding activity at the highest concentration. Under starvation, exposed larvae activated the antioxidant defenses by increasing the total glutathione levels and inhibiting catalase activity, which seemed efficient to prevent oxidative damage. Such larvae also presented increased energy consumption potentially related to oxidative damage prevention and decreased neurotransmission. Biochemical responses of fed larvae showed a similar trend, except for LPO, which remained unaffected, except at 0.1 mg/PE-MPs/L. Our results suggest that small-sized MPs in finfish hatcheries may compromise larvae nutritional requirements, but at considerably higher levels than those reported in marine environments. Nevertheless, cumulative adverse effects due to lower MPs concentrations may occur