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Interdisciplinary Centre of Marine and Environmental Research

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Editorial: Emerging topics in coastal and transitional ecosystems: science, literacy, and innovation
Publication . Duarte, Bernardo; Teixeira, Célia M.; Martins, Irene; Engelen, Aschwin; Costa, Raquel L.; Adams, Janine Barbara; Bebianno, Maria João; Melo, Ricardo A.; Fonseca, Vanessa F.
Marine coastal and transitional ecosystems are facing increasing impacts, and often reflect the most immediate effects of environmental change, habitat destruction, and biodiversity loss. With over half of the population currently living in coastal areas, these areas are of interest for multiple uses and resources, as well as subjected to multiple stressors and associated impacts derived from local and upstream anthropogenic activities. The challenges coastal and transitional ecosystems now face is not new and have far-reaching implications for the ocean (Borja et al.). Nevertheless, significant knowledge gaps on their functioning and structure still exist and new solutions or approaches to this old problem are still needed, from blue biotechnological innovations to improved ocean literacy (Borja et al.). This Research Topic aimed to contribute to the sustainability of coastal and transitional environments, providing a broad overview of ecosystem resources and functioning, assessment and monitoring tools, restoration, biotechnology, and ocean literacy. A growing human population has also increased the reliance on the sea for food and feed resources. Despite soaring demand, the management of seafood resources is still hampered by key knowledge gaps on many life-history traits of target species as well as on ecosystem’s functioning (Golden et al., 2021). From tropical regions, where mangroves function as nursery habitats for various crustaceans and fish species, contributing to maintaining adjacent marine stocks, a poorly studied system on Príncipe Island, Gulf of Guinea, evidenced the importance of seasonality and mangrove zone on fish assemblages (Cravo et al.). In the deep sea, a particular challenge to commercial exploitation of fish species is how changing environmental conditions affect these organisms, which are generally characterized by high longevity, late reproduction, and low fecundity.
Dietary methionine supplementation improves the European seabass (Dicentrarchus labrax) immune status following long-term feeding on fishmeal-free diets
Publication . Machado, Marina; Engrola, Sofia; Colen, R.; Conceicao, Luis E. C.; Dias, Jorge; Costas, Benjamin
Methionine is a limiting amino acid (AA) in fish diets, particularly in those containing high levels of plant protein (PP), and is key in the immune system. Accordingly, outcome on the fish immune mechanisms of methionine-deficient and methionine-supplemented diets within the context of 0 % fishmeal formulation, after a short and prolonged feeding period, was studied in European seabass (Dicentrarchus labrax). For this, seabass juveniles were fed a (i) fishmeal-free diet, meeting AA requirements, but deficient in methionine (MET0·65); (ii) as control, the MET0·65 supplemented with L-methionine at 0·22 % of feed weight (CTRL); (iii) two diets, identical to MET0·65 but supplemented at 0·63 and 0·88 % of feed weight of L-methionine (MET1·25 and MET1·5, respectively); and (iv) a fishmeal-based diet (FM), as positive control. After 2 and 12 weeks of feeding, blood and plasma were sampled for leucocyte counting and humoral parameter assays and head-kidney collected for gene expression. After 2 weeks of feeding, a fishmeal-free diet supplemented with methionine led to changes in the expression of methionine- and leucocyte-related genes. A methionine immune-enhancer role was more evident after 12 weeks with an increased neutrophil percentage and a decreased expression of apoptotic genes, possibly indicating an enhancement of fish immunity by methionine dietary supplementation. Furthermore, even though CTRL and FM present similar methionine content, CTRL presented a reduced expression of several immune-related genes indicating that in a practical PP-based diet scenario, the requirement level of methionine for an optimal immune status could be higher.

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Funding agency

Fundação para a Ciência e a Tecnologia

Funding programme

6817 - DCRRNI ID

Funding Award Number

UID/Multi/04423/2019

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