Percorrer por autor "Soares, Amadeu M. V. M."
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- Dominant effects of the antiepileptic drug carbamazepine over climate change stressors on mytilus galloprovincialis toxicityPublication . Nascimento Bajwa, Farhat-Un-Nisá; Cunha, Marta; Vilke, Juliano Marcelo; Dias Duarte Fragoso, Bruno; Borges, Rodrigo; Soares, Amadeu M. V. M.; Freitas, Rosa; GARCIA DA FONSECA, TAINÁPharmaceuticals have become ubiquitous in marine realms, raising concerns about their ecological effects. This study investigates the ecotoxicological impact of the antiepileptic drug carbamazepine on marine mussels (Mytilus galloprovincialis) under increased seawater temperature and salinity, reflecting projected climate change scenarios. Mussels were exposed to carbamazepine (CBZ, 5 μg L− 1 ) for 28 days in both current (17 ◦C and salinity 35) and predicted (23 ◦C and salinity 40) conditions. A multiple-biomarker approach was employed to assess alterations in energy balance, antioxidant and biotransformation systems, membrane damage, neurotoxicity, and genotoxicity in gills and digestive glands. The results indicated that CBZ caused significant oxidative stress, disruption in energy metabolism, and neurotoxic and genotoxic effects, regardless of the combination of stressors. Moreover, biomarkers were modulated by the time of exposure, suggesting a time-specific response in mussels exposed to either a single or multiple stressors. The findings underscore the complex interplay between pharmaceutical pollution and climate change stressors. This study provides crucial insights into the toxicity of pharmaceuticals in marine environments under future climate change scenarios. To our knowledge, this is the first study to investigate the effects of CBZ on marine mussels in conjunction with the simultaneous rise in seawater temperature and salinity.
- Sustainable feed formulation to community‐based aquaculture: Oreochromis niloticus fingerlings performance and antioxidant statusPublication . Pires, Sílvia F. S.; Vital, Inês; Pereira, Vitória; Bustani, Henriques; Aragão, Cláudia; Engrola, Sofia; Cabano, Miguel; Dias, Jorge; Soares, Amadeu M. V. M.; Rodrigues, Andreia C. M.; Rocha, Rui J. M.Community-based aquaculture can reduce dependence on natural resources, promote biodiversity conservation, and improve local economies and food security. However, this activity is highly dependent on local conditions regarding natural resources, such as the availability of produced organisms, adequate feeds, and environmental factors. As ectothermic organisms, fish are more susceptible to temperature fluctuations in culture conditions. A set of raw ingredients (e.g., cassava and local beans) produced or available in villages from Cabo Delgado (Mozambique) with nutritional potential for fish feed were selected to produce an experimental diet. The following objectives were defined: (1) evaluate growth performance of tilapia fingerlings fed a diet produced with local ingredients, compared with a commercial-like diet; and (2) evaluate the response to thermal stress (18, 26, and 32degree celsius) by tilapia fingerlings fed with tested diets. Tilapia fed with an experimental diet presented lower growth rates, lower DNA damage, higher neurophysiological, and antioxidant activity, leading to increased oxidative stress. Regarding energy budget, tilapia fed with the experimental diet presented higher protein content at 26degree celsius and lipids at 18degree celsius, leading to greater energy available at these temperatures. Overall, local ingredients can be successfully used as an additional feed source for tilapia production in community-based aquaculture in earthen ponds.
- The effect of mixotrophy in the ex situ culture of the soft coral Sarcophyton cf. glaucumPublication . Costa, Ana P. L.; Calado, Ricardo; Marques, Bruna; Lillebo, Ana I.; Serôdio, João; Soares, Amadeu M. V. M.; Serrão, Ester; Rocha, Rui J. M.In toto aquaculture is a promising approach towards the bioprospecting and production of bioactive compounds from the coral holobiont. Coral aquaculture ex situ allows a better control of culture conditions to maximize coral growth and reduce production costs. Light (either the Photosynthetically Active Radiation-PAR, or the emitted spectrum) is one of the most important factors affecting the growth of symbiotic corals, due to their association with photosynthetic dinoflagellates. Additionally, the balance between autotrophy and heterotrophy is also known to play a key role in the successful growth of mixotrophic corals. The present study aimed to evaluate the effect of: 1) light spectrum (white and blue light), 2) PAR intensity (50 and 120 mu mol quanta m(-2) s(-1)), and 3) heterotrophic feeding (rotifers-Brachionus plicatilis), in the physiology, photobiology and growth of coral fragments obtained from three mother colonies of the mixotrophic soft coral Sarcophyton cf. glaucum, cultured ex situ in recirculated systems during 80 days. The supply of rotifers did not affect coral growth and promoted the increase of dissolved inorganic nitrogen and phosphorous concentrations (DIN and DIP, respectively) in the water column. Coral fragments originating from the different mother colonies presented distinct responses to the tested light PAR intensities and spectra, as well as to the interaction of these factors with the supply of rotifers. We concluded that the variability displayed between different mother colonies of the same species can affect the growth response of corals under contrasting scenarios of mixotrophy. Statement of relevance: Improvement of in toto aquaculture of Sarcophyton cf. glaucum. (C) 2015 Elsevier B.V. All rights reserved.
- Thyroid disruption in the lizard Podarcis bocagei exposed to a mixture of herbicides: a field studyPublication . Bicho, Rita C.; Amaral, Maria José; Faustino, Augusto M. R.; Power, Deborah; Rêma, Alexandra; Carretero, Miguel A.; Soares, Amadeu M. V. M.; Mann, Reinier M.Pesticide exposure has been related with thyroid disrupting effects in different vertebrate species. However, very little is known about the effects of these compounds in reptiles. In the Mediterranean area, lacertid lizards are the most abundant vertebrate group in agroecosystems, and have been identified as potential model species for reptile ecotoxicology. The aim of this study was to understand if the herbicides applied in corn fields have thyroid disruptive effects in the lizard Podarcis bocagei. Adult male lizards were captured in north-western Portugal in corn fields treated with herbicides (exposed sites), and in organic agricultural fields (reference sites). Thyroid and male gonad morphology and functionality, and testosterone levels were investigated through histological, immunohistochemical and biochemical techniques. Lizards from exposed locations displayed thyroid follicular lumens with more reabsorption vacuoles and significantly larger follicular area than those from reference fields. Furthermore, testes of lizards from exposed locations had significantly larger seminiferous tubule diameters, significantly higher number of spermatogenic layers and displayed an upregulation of thyroid hormone receptors when compared with lizards from reference areas. These findings strongly suggest that the complex mixture of herbicides that lizards are exposed to in agricultural areas have thyroid disrupting effects which ultimately affect the male reproductive system. Alachlor, which has demonstrated thyroid effects in mammals, may be largely responsible for the observed effects.