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- Characterising different artisanal fishing gears catches that operate in distinct habitats to assess ichthyofauna assemblages in Bons Sinais estuary, MozambiquePublication . Jeremias J. Mocuba; Eudriano F.S. Costa; Daniel Oliveira Mualeque; Maria Alexandra Teodósio; Francisco Leitão; Mocuba, Jeremias; Florêncio dos Santos Costa, Eudriano; Teodosio, Maria; Leitão, FranciscoMonitoring the ichthyofauna is crucial to detect changes in aquatic communities for fisheries management and conservation. This study aimed to identify the most effective gear for ichthyofauna studies in the estuary. Thus, the performance of the beach seine (active gear) and chicocota (fixed gear), common fishing gears used by artisanal fishers in the Bons Sinais estuary (BSE), were used to characterise fish assemblage structure. Monthly surveys were conducted at two fixed sample points of the BSE to assess the composition of the fish assemblage. The analysis revealed statistical differences in abundance, biomass, and the presence/absence of different species between gears regardless sampling months. At ecological level, differences among gears were explained by different modus operandi, technological features and also different sampling habitats where gears operate; beach seine is catching bottom-bound and littoral fish while Chicocota is sampling the pelagic assemblage of the mid-channels. The frequency of occurrence of the 13 most abundant species differed between gears. Both gears showed little size-selectivity, with the mean total length and mean body height of these species statistically differing between gears. A total of 92 fish species were identified. No statistical differences were observed among gears for species richness, diversity and evenness. Both fishing gears captured several local socio-economically important species in the BSE. In particular, 13 of the most important species accounted for more than 54% and 60% of the total abundance and biomass in beach seine and chicocota, respectively. The complementary use of fixed and active fishing gears for studying fish community structure in estuaries is recommended. This multi-gear sampling approach enhances the capacity to detect changes in fish communities and provides valuable data for fisheries management and conservation efforts.
- Characterising different artisanal fishing gears catches that operate in distinct habitats to assess ichthyofauna assemblages in Bons Sinais estuary, MozambiquePublication . Mocuba, Jeremias; Florêncio dos Santos Costa, Eudriano; Mualeque, Daniel Oliveira ; Teodosio, Maria; Leitão, FranciscoMonitoring the ichthyofauna is crucial to detect changes in aquatic communities for fisheries management and conservation. This study aimed to identify the most effective gear for ichthyofauna studies in the estuary. Thus, the performance of the beach seine (active gear) and chicocota (fixed gear), common fishing gears used by artisanal fishers in the Bons Sinais estuary (BSE), were used to characterise fish assemblage structure. Monthly surveys were conducted at two fixed sample points of the BSE to assess the composition of the fish assemblage. The analysis revealed statistical differences in abundance, biomass, and the presence/absence of different species between gears regardless sampling months. At ecological level, differences among gears were explained by different modus operandi, technological features and also different sampling habitats where gears operate; beach seine is catching bottom-bound and littoral fish while Chicocota is sampling the pelagic assemblage of the midchannels. The frequency of occurrence of the 13 most abundant species differed between gears. Both gears showed little size-selectivity, with the mean total length and mean body height of these species statistically differing between gears. A total of 92 fish species were identified. No statistical differences were observed among gears for species richness, diversity and evenness. Both fishing gears captured several local socio-economically important species in the BSE. In particular, 13 of the most important species accounted for more than 54% and 60% of the total abundance and biomass in beach seine and chicocota, respectively. The complementary use of fixed and active fishing gears for studying fish community structure in estuaries is recommended. This multigear sampling approach enhances the capacity to detect changes in fish communities and provides valuable data for fisheries management and conservation efforts.
- Strategy combining mammalian fats with supplementation of pungent spices in aquafeeds, to mitigate negative impacts of fish oil replacement in fish performance, fillet quality and hepatic condition of gilthead seabream (Sparus aurata)Publication . Ruiz, Alberto; Gisbert, Enric; Estevez, Alicia; Reyes-López, Felipe E.; Vallejos-Vidal, Eva; Tort, Lluís; Dias, Jorge; Engrola, Sofia; Magalhães, Sara; Aires, Tiago; Morais, SofiaThe replacement of fish oil (FO) in aquafeeds usually leads to imbalances in the dietary content of n-3 and n-6 polyunsaturated fatty acids (PUFA), with negative consequences for fish performance, health, and fillet quality. Animal-rendered fats are an alternative lipid source high in saturated fatty acids, potentially sparing n-3 PUFA from oxidation, and with lower n-6 PUFA contents than plant-based oils, especially in the case of mammalian fats (MF). Hence, this work assessed the effect of replacing 45% FO by MF (negative control, NC) compared to a diet containing only FO (positive control, PC) in gilthead seabream (Sparus aurata, initial body weight: 85 ± 4 g, mean ± standard deviation) at low water temperature. In addition, we studied the effect of supplementing the NC diet with a combination of pungent spices with hypolipidemic and anti-inflammatory properties at three inclusion levels: 0.05 (SPICY0.05%), 0.1 (SPICY0.1%), and 0.15% (SPICY0.15%). At the end of the trial (112 days), FO substitution by MF led to poorer fish performance in terms of body weight (BW), specific growth rate (SGR), feed conversion ratio (FCR), and protein efficiency ratio (PER). Supplementation of the NC diet with spices numerically improved SGR, FCR and PER at all inclusion levels (non-significantly different from the PC group), being FCR and PER significantly different from the NC group in the SPICY0.1% and SPICY0.15% treatments. A remarkable increase in lipid level was observed in fillets of fish fed the NC diet, but was fully counteracted by spice supplementation, especially in fish fed the SPICY0.15% diet. A lower fat accumulation was also found in the liver of fish fed the SPICY0.1% and SPICY0.15% diets, with respect to the PC and NC groups. The fillets' fatty acid profile mostly reflected the diet composition, but the SPICY0.15% diet modified it in an inverse direction to that observed in the NC, to more closely resemble the profile of fish fed the PC diet. In particular, the SPICY0.15% diet reduced fillet levels of MUFA, linoleic and linolenic acids, and increased n-3 LC-PUFA (including EPA and DHA), compared to the NC. A microarray-based transcriptomic analysis revealed a better hepatic health status, as indicated by different biological processes associated to immunity. Overall, supplementation with the combination of pungent spices at 0.15% enabled the incorporation of alternative lipid sources, such as MF, in aquafeeds without significantly compromising growth and feeding performance, liver health, and quality of the edible product.
- Evolution of chitin-synthase in molluscs and their response to ocean acidificationPublication . Cardoso, João; Power, Deborah Mary; Peng, MaoxiaoChitin-synthase (CHS) is found in most eukaryotes and has a complex evolutionary history. Research into CHS has mainly been in the context of biomineralization of mollusc shells an area of high interest due to the consequences of ocean acidification. Exploration of CHS at the genomic level in molluscs, the evolution of isoforms, their tissue distribution, and response to environmental challenges are largely unknown. Exploiting the extensive molecular resources for mollusc species it is revealed that bivalves possess the largest number of CHS genes (12-22) reported to date in eukaryotes. The evolutionary tree constructed at the class level of molluscs indicates four CHS Type II isoforms (A-D) probably existed in the most recent common ancestor, and Type II-A (Type II-A1/Type II-A-2) and Type II-C (Type II-C-1/Type II-C-2) underwent further differentiation. Non-specific loss of CHS isoforms occurred at the class level, and in some Type II (B-D groups) isoforms the myosin head domain, which is associated with shell formation, was not preserved and highly species-specific tissue expression of CHS isoforms occurred. These observations strongly support the idea of CHS functional diversification with shell biomineralization being one of several important functions. Analysis of transcriptome data uncovered the species-specific potential of CHS isoforms in shell formation and a species-specific response to ocean acidification (OA). The impact of OA was not CHS isoform-dependent although in Mytilus, Type I-B and Type II-D gene expression was down-regulated in both M. galloprovincialis and M. coruscus. In summary, during CHS evolution the gene family expanded in bivalves generating a large diversity of isoforms with different structures and with a ubiquitous tissue distribution suggesting that chitin is involved in many biological functions. These findings provide insight into CHS evolution in molluscs and lay the foundation for research into their function and response to environmental changes.
- Quantitative PCR assays as a monitoring tool for bacterial genera in fresh fish filletsPublication . Pinto, Patricia IS; NAJAFPOUR, BABAK; Lima, Pedro; P. Machado; Aires, Tania; Engelen, Aschwin; Tsironi, T.; Anjos Guerreiro, Liliana Isabel Tomé; Power, Deborah MaryFresh fish fillets are a valuable but highly perishable food, and their rapid microbial deterioration is a drawback for food safety and sustainability of aquaculture, food and retail industries. Quantitative PCR (qPCR) assays based on 16S rRNA gene (16S) sequences were developed for the most abundant bacteria genera detected by metagenomics in fresh or processed fish fillets. The efficiency and specificity of six qPCR assays (for 16S of all bacteria or genera Shewanella, Pseudomonas, Carnobacterium, Janthinobacterium and Massilia) was verified using in silico predictions, cloning, sequencing and phylogenetic analyses of amplicons obtained from refrigerated control or high-pressure processed (HPP) European sea bass (Dicentrarchus labrax) fillets. In HPP sea bass fillets, significant decreases in total bacteria 16S and of Shewanella, Pseudomonas, Carnobacterium and Janthinobacterium 16S compared to control fillets were confirmed by qPCR, after 11 days of refrigerated storage. The qPCR assays were successfully applied to monitor microbial contamination during refrigerated storage of fresh fillets from commercial (retail) sea bass and gilthead sea bream (Sparus aurata). Significant increases in total bacterial and Shewanella, Pseudomonas, Carnobacterium and Janthinobacterium contamination were detected after 7-14 days. 16S copy number for total bacteria and the four target genera positively correlated with total viable counts using culture enumeration. 16S of Massilia, that is abundant in fresh fish fillets, did not significantly change during storage. The six validated qPCR assays developed are proposed as specific, sensitive, culture-independent methods for monitoring quality or processing outcomes for fish fillets during cold chain storage.
- Integrating musealized archaeological sediment collections into current geoarchaeological analytical frameworks for sustainable research practicesPublication . Costanzo, Stefano; Pappalardo, Marta; Starnini, Elisabetta; Rossoni-Notter, Elena; Notter, Olivier; Moussous, Abdelkader; Soares Remiseiro, Miguel; Soares-Remiseiro, Miguel; Fermo, Paola; Cremaschi, Mauro; Zerboni, AndreaWe present a review of the latest framework achievements in geoarchaeological sciences applied to microstratigraphic and biomolecular studies of prehistoric archaeological contexts, highlighting the importance of musealized archaeological stratigraphies. We assess how today's scientific and technological accomplishments can be tailored for archaeological human ecology studies with analytical ensembles that provide unprecedented results. Sampling and processing workflows originating from resin consolidation and thin section micromorphology of undisturbed blocks of archaeological soils and sediments, guarantee subsampling accuracy at the micrometre scale granting access to individual components otherwise impossible to target: the achievable information yield makes even the smallest soil samples potential sources of pioneering discoveries. Yet, archaeological excavations are still the primary mode of retrieving new soil samples. We argue that, when dealing with archaeological sites that were excavated and partially musealised in the past, the exploration of related museum collections should be prioritized as perspective source of new study samples. Analysing old and potentially very informative samples, with an approach that we define as "Green Archaeology ", may represent a source of well-structured primary data as well as a means for planning new excavations, delivering novel discoveries while safeguarding site integrity and promoting Third Mission valorisation of sites and heritage dormant collections.
- Charting sustainable waters: governance challenges and opportunities for fisheries and coastal beach resources in a West African countryPublication . Takyi, Richard; Nunoo, Francis Kofi Ewusie; El Mahrad, Badr; Addo, Cynthia; Essandoh, JohnMarine fisheries and beaches (i.e., backshore, foreshore and shoreface) are essential for providing ecosystem services globally, with coastal states being at the forefront of this benefit. Consequently, several policies, legislations, and governance processes must be formulated to ensure their sustainable use due to the impact of anthropogenic and natural pressures. This study aims to analyse the legal and institutional frameworks for the management of marine fisheries and beach resources (such as flora (coconut), fauna (ghost crabs), dunes, and rocky components) under key international laws and conventions, using Ghana as a case study. The study identifies the strengths, weaknesses, opportunities, and threats (SWOT) within resource management, as well as their impact on the country's progress in the attainment of the Sustainable Development Goals (SDGs) and Africa Union Agenda 2063. Data was collected through interviews with fishers, coastal residents, and other relevant stakeholders, as well as a review of secondary data. The results unveil a distinctive contrast in the regulatory landscape between fisheries and beach resources. While numerous policies have been formulated to ensure the sustainable management of fisheries, the same level of attention and commitment has not been extended to beach resources. The SWOT analysis revealed that some of the strengths in the governance of marine fisheries and beach resources rest on the availability of institutions and laws. The weakness lies in inadequate enforcement and data gathering and analyses to inform decision making. This study provides as an illuminating exploration into the legal and institutional underpinnings of marine fisheries and beach resource management in Ghana, shedding light on the critical junctures where improvements are needed.
- A bioeconomic model for a multispecies small-scale fishery systemPublication . Azevedo, Eric; Pintassilgo, Pedro; Dantas, David; Daura-Jorge, Fábio GonçalvesA fishery encompasses various interconnected systems, including ecological, socioeconomic, and governing systems. Managing fisheries requires the simultaneous consideration of all these systems, making it a challenging endeavor. To address these challenges, fisheries bioeconomic models have emerged as a crucial tool. They are particularly valuable in the context of small-scale fisheries, which are often complex, overlooked and poorly understood. Thus, this paper presents a dynamic multispecies and multigear bioeconomic model that can illuminate the ecological, economic, and social dimensions of small-scale fisheries under different management scenarios. The model was applied to a small-scale fisheries system in Southern Brazil that has as a notable feature a cooperative fishing behavior between dolphins and fishers. Three scenarios were explored: the base scenario (status quo), the optimal management scenario, and the constrained optimal management scenario. The model outputs demonstrated a clear tradeoff between labour effort, species conservation, and economic rent. Shifting from the base to an optimal management scenario would result in a labour employment reduction within the system but concurrently yield higher stock levels, economic rent, and wages. These results illustrate how our model can explore critical management scenarios across the multiple dimensions of fisheries systems. In essence, this research offers a novel contribution in the form of a bioeconomic model tailored for small-scale fisheries involving multiple species.
- Melatonin production improves Senegalese sole sperm motility at night, but fails as a supplement during cryopreservationPublication . Félix de Azeredo Pinto e Melo, Francisca; Ferrão, Leonor; Gallego, Victor; Oliveira, Catarina; Cabrita, ElsaMelatonin is a powerful antioxidant present in fish seminal plasma. This study aimed to understand melatonin's endogenous and exogenous effects on first-generation Senegalese sole sperm quality for sperm management applications. In the first experiment, samples were collected at mid-light (ML) and mid-dark (MD) daytimes, to evaluate the effects on sperm motility. In a second experiment, using confocal microscopy and melatonin-FITC, spermatozoa permeability to melatonin was evaluated and, after showing that it enters the nucleus and mitochondria by passive diffusion, exogenous melatonin toxicity and antioxidant potential during a cryopreservation assay were performed. The toxicity assay tested different melatonin concentrations (0.01, 0.1, 1, and 10 mM) and exposure times (3, 5, 15 and 30 min), and sperm motility parameters were measured (TM, PM, VCL, VSL, LIN) using CASA system. The best conditions (0.1 and 10 mM) were selected for the cryopreservation assay, and a set of post-thaw sperm quality analyses were performed (motility, viability, reactive oxygen species, lipid peroxidation, and DNA fragmentation). The motility analyzed at ML and MD showed significant differences in all parameters, mainly on velocities (VCL, VSL, VAP), that were significantly higher at MD. Supplemented melatonin did not influence spermatozoa motility, MDA content or DNA fragmentation, although a lower percentage of viable cells was obtained on the 10 mM treatment. Altogether, Senegalese sole spermatozoa motility was enhanced at night, putatively by endogenous melatonin through direct or indirect mechanisms, whereas supplemented melatonin did not confer extra protection during cryopreservation.
- Cytotoxic, antioxidant, and enzyme inhibitory activities of centaurea stapfiana extracts and their HPLC-ESI-QTOF-MS profiles: Insights into an unexplored centaurea speciesPublication . Zengin, Gokhan; Fernández-Ochoa, Álvaro; Cádiz-Gurrea, María de la Luz; Jiménez, Francisco-Javier Leyva; Uba, Abdullahi Ibrahim; Ak, Gunes; Soomro, Sanam Iram; Balos, Maruf; Cakilcioglu, Ugur; Rodrigues, Maria João; Guerreiro Pereira, Catarina Alexandra; Custódio, LuísaThe members of the genus Centaurea have a great interest in pharmaceutical and nutraceutical fields due to their biological potential. Based on this information, we aimed to evaluate the biological properties (antioxidant, enzyme inhibition and cytotoxicity) and chemical profile of the extract of Centaurea stapfiana, , an unstudied species. The highest total phenolic content was found in the ethanol/water extract with 32.17 mg GAE/g. A total of 102 of them were identified by HPLC-ESI-QTOF-MS analysis. These compounds were mainly hydroxybenzoic acid and hydroxycinnamic acid as well as flavonoids. In the antioxidant tests, the ethanol/water extract had the best free radical scavenging and reducing ability. However, in the enzyme inhibition test, the ethanol extract was the most active. The extracts were also tested on two tumour cell lines (RAW 264.7 and HepG2) and one non- tumour cell line (S17). The ethanol extract showed the promising effect on HepG2 (cell viability: 28.6 % at 50 g/ml). Furthermore, we examined the interactions between the compounds and enzymatic and cellular targets. A good interaction was found between quercetin-3-xylosyl-(1- > 6)-glucoside and iNOS. In summary, our results suggest that C. stapfiana can be considered as a versatile raw material for the development of health- promoting applications in the pharmaceutical and cosmeceutical fields.