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Henrique N. Cabral - One of the best experts on this subject based on the ideXlab platform.
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Modelling larval dispersal dynamics of common sole (Solea Solea) along the western Iberian coast
Progress in Oceanography, 2017Co-Authors: Susanne E. Tanner, Ana Teles-machado, Filipe Martinho, Álvaro Peliz, Henrique N. CabralAbstract:Abstract Individual-based coupled physical-biological models have become the standard tool for studying ichthyoplankton dynamics and assessing fish recruitment. Here, common sole ( Solea Solea L.), a flatfish of high commercial importance in Europe was used to evaluate transport of eggs and larvae and investigate the connectivity between spawning and nursery areas along the western Iberian coast as spatio-temporal variability in dispersal and recruitment patterns can result in very strong or weak year-classes causing large fluctuations in stock size. A three-dimensional particle tracking model coupled to Regional Ocean Modelling System model was used to investigate variability of sole larvae dispersal along the western Iberian coast over a five-year period (2004–2009). A sensitivity analysis evaluating: (1) the importance of diel vertical migrations of larvae and (2) the size of designated recruitment areas was performed. Results suggested that connectivity patterns of sole larvae dispersal and their spatio-temporal variability are influenced by the configuration of the coast with its topographical structures and thus the suitable recruitment area available as well as the wind-driven mesoscale circulation along the Iberian coast.
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Anomalous otoliths in juveniles of common sole,Solea Solea, and Senegal sole,Solea senegalensis
Marine Biology Research, 2014Co-Authors: Catarina Vinagre, Rachid Amara, Anabela Maia, Henrique N. CabralAbstract:AbstractThe otoliths of wild common sole, Solea Solea, and Senegal sole, Solea senegalensis, from the Tagus and the Douro estuaries, and captive S. senegalensis were examined for the detection of anomalies. The anomalies detected were granules of crystals, a dark coloration over the entire otolith, a dark mark concentric to the nucleus and multiple nuclei. A higher proportion of anomalies was found in wild individuals of these species (16–63%) than is usually reported for other species. Captive S. senegalensis exhibited an incidence of anomalies within the range previously reported for other species also reared in captivity. The oceanographic–climatic conditions of the Portuguese coast, which cause strong and abrupt changes in water temperature, salinity and mineral composition, may be an important factor contributing to or causing otolith anomalies. Heatwaves, intense solar radiation and anthropogenic pollution affecting the estuarine nursery grounds may also play an important role. However, more experim...
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Population connectivity of Solea Solea and Solea senegalensis over time
Journal of Sea Research, 2013Co-Authors: Susanne E. Tanner, Patrick Reis-santos, Rita P. Vasconcelos, Simon R. Thorrold, Henrique N. CabralAbstract:Abstract A better understanding of connectivity patterns between estuarine and coastal areas is fundamental towards sustainable management of estuarine associated fish and identification of ecologically important habitats. Otolith geochemistry (Li:Ca, Mg:Ca, Mn:Ca, Sr:Ca, Ba:Ca, Pb:Ca) determined in juveniles of Solea Solea and Solea senegalensis in two year classes was used to determine the estuaries of origin of age 3 + and age 2 + fish sampled off the Portuguese coast. The contributions of estuarine nursery areas to coastal adult populations obtained using maximum likelihood estimation varied significantly over the two years. However, one estuary (Ria Aveiro) consistently contributed a large proportion (30%–87%) to the adult populations of both sole species while a second estuary (Mira) contributed almost no adults (0%–3%). Comparison of otolith geochemistry between juveniles from characterized estuarine nurseries and adults indicated that unknown nursery areas may have contributed to the coastal adult populations, particularly in one year class. Nevertheless, the estimated relative contributions, based on otolith geochemistry, successfully identified the estuarine systems that accounted for most of the recruitment to adult stocks in the two years. Ultimately, this information should promote the development of effective conservation strategies and integrated fisheries management plans for these two commercially important species.
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Lipid‐based indicators of nutritional condition in juvenile sole Solea Solea
Journal of Applied Ichthyology, 2012Co-Authors: Vanessa F. Fonseca, Luís Narciso, Henrique N. CabralAbstract:Summary Effects of the feeding level on juvenile Solea Solea (Linnaeus, 1758) lipid-related indicators of nutritional condition were assessed in a 25-day trial experiment. Morphometric indices (K and HSI), liver lipid content and fatty acids (FA) clusters were good indicators of the feeding level, while individual FA showed highly dynamic variation patterns. Additionally, liver indices were more sensitive to feeding stress than were muscle measurements. HSI determination (and K) is fairly straightforward, with lower costs and simple procedures. Nevertheless, liver lipid content is also an important indicator of the feeding level and constitutes a direct measurement of food utilization and energy storage capacity. The individual variability and complex dynamics of FA with the feeding level are disadvantageous for use in FA analysis even for early-warning signals of feed limitation. Overall, S. Solea nutritional condition can be suitably assessed by morphometric indices and lipid content, especially considering liver measurements (HSI and liver lipid content), provided that the fish development stage is accounted for (i.e. gonad development and reproductive cycle).
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Ecophys.Fish perspectives on growth of juvenile soles, Solea Solea and Solea senegalensis, in the Tagus estuary, Portugal
Journal of Sea Research, 2009Co-Authors: Vanessa F. Fonseca, William H. Neill, John M. Miller, Henrique N. CabralAbstract:Abstract Ecophys.Fish, an ecophysiological framework to simulate fish growth in time-varying environments, was parameterized for two sole species, Solea Solea (Linnaeus, 1758) and Solea senegalensis Kaup, 1858. The model gave reliable predictions of soles' growth and metabolic rates from published data under controlled environments. Differences in model parameters reflected specie's different environmental optima and were in accordance with their distributional range — northern range of S. Solea and a southern range of S. senegalensis . Field application of this model to resolve the effects of varying habitat conditions on juvenile soles' growth in the Tagus estuary (Portugal), during the spring–summer period from 2003 to 2006, highlighted spatial and temporal differences in soles' metabolic scope for growth and estimated growth rates. Higher growth estimates were obtained for S. Solea and S. senegalensis in Vila Franca de Xira during 2006, and for S. senegalensis in Alcochete during 2003, 2004 and 2006, and were fairly well explained by natural variation in abiotic conditions. Overall, the Ecophys.Fish model gave accurate field predictions of each sole species' growth rate and proved to be a useful tool for monitoring and assessment of habitat quality for juvenile sole.
Jan Atle Knutsen - One of the best experts on this subject based on the ideXlab platform.
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Feeding behaviour of North Sea turbot (Scophthalmus maximus) and Dover sole (Solea Solea) larvae elicited by chemical stimuli
Marine Biology, 1992Co-Authors: Jan Atle KnutsenAbstract:The effect of chemical stimuli on the feeding behaviour of turbot ( Scophthalmus maximus L.) and sole ( Solea Solea L.) larvae was investigated under controlled laboratory conditions. Laboratory-reared flatfish larvae exposed to chemical stimuli showed significant differences in the frequency of various behaviour patterns related to feeding (such as swimming, snapping and darting) compared to larvae exposed to blanks of filtrated seawater. The chemical substances Il-asparagine, glycine, inosine 5-monophosphate and betaine evoked the strongest behavioural responses in turbot larvae. In sole larvae the most potent substances were Il-phenylalanine, Il-lysine, Il-asparagine, inosine 5-monophosphate and betaine. These results show that feeding of turbot and sole larvae is influenced by chemosensory processes at an early larval stage, and indicate that chemoreception may be an integrated part of turbot and sole larvae feeding strategy.
D Lowe - One of the best experts on this subject based on the ideXlab platform.
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Histopathology of the skin of UV-B irradiated sole (Solea Solea) and turbot (Scophthalmus maximus) larvae.
Marine environmental research, 2000Co-Authors: I Mcfadzen, S Baynes, J Hallam, A Beesley, D LoweAbstract:Larval stages of two economically important flatfish, the sole (Solea Solea) and turbot (Scophthalmus maximus) were exposed to ambient and elevated levels of UV-B. Sole larvae, which naturally occur in the plankton in early spring, demonstrated skin lesions at elevated levels of UV-B. Histopathology of the sole revealed cellular changes in the integument, characteristic of sunburn damage, with a reduction in the size of mucus-secreting cells and an increased epidermal thickening, especially at the highest doses of UV-B (2.15 KJ bio eff/m2). Pigmentation in the sole is restricted to a few isolated melanocytes. The integrity of the heavily pigmented skin of turbot appeared to be unaffected by comparable doses of UV-B. Both species have protective mechanisms, which minimize the effects of naturally-occurring levels of UV-B. However, sole appear to be poorly adapted to accommodate any further increase in solar radiation.
Vanessa F. Fonseca - One of the best experts on this subject based on the ideXlab platform.
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Lipid‐based indicators of nutritional condition in juvenile sole Solea Solea
Journal of Applied Ichthyology, 2012Co-Authors: Vanessa F. Fonseca, Luís Narciso, Henrique N. CabralAbstract:Summary Effects of the feeding level on juvenile Solea Solea (Linnaeus, 1758) lipid-related indicators of nutritional condition were assessed in a 25-day trial experiment. Morphometric indices (K and HSI), liver lipid content and fatty acids (FA) clusters were good indicators of the feeding level, while individual FA showed highly dynamic variation patterns. Additionally, liver indices were more sensitive to feeding stress than were muscle measurements. HSI determination (and K) is fairly straightforward, with lower costs and simple procedures. Nevertheless, liver lipid content is also an important indicator of the feeding level and constitutes a direct measurement of food utilization and energy storage capacity. The individual variability and complex dynamics of FA with the feeding level are disadvantageous for use in FA analysis even for early-warning signals of feed limitation. Overall, S. Solea nutritional condition can be suitably assessed by morphometric indices and lipid content, especially considering liver measurements (HSI and liver lipid content), provided that the fish development stage is accounted for (i.e. gonad development and reproductive cycle).
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Ecophys.Fish perspectives on growth of juvenile soles, Solea Solea and Solea senegalensis, in the Tagus estuary, Portugal
Journal of Sea Research, 2009Co-Authors: Vanessa F. Fonseca, William H. Neill, John M. Miller, Henrique N. CabralAbstract:Abstract Ecophys.Fish, an ecophysiological framework to simulate fish growth in time-varying environments, was parameterized for two sole species, Solea Solea (Linnaeus, 1758) and Solea senegalensis Kaup, 1858. The model gave reliable predictions of soles' growth and metabolic rates from published data under controlled environments. Differences in model parameters reflected specie's different environmental optima and were in accordance with their distributional range — northern range of S. Solea and a southern range of S. senegalensis . Field application of this model to resolve the effects of varying habitat conditions on juvenile soles' growth in the Tagus estuary (Portugal), during the spring–summer period from 2003 to 2006, highlighted spatial and temporal differences in soles' metabolic scope for growth and estimated growth rates. Higher growth estimates were obtained for S. Solea and S. senegalensis in Vila Franca de Xira during 2006, and for S. senegalensis in Alcochete during 2003, 2004 and 2006, and were fairly well explained by natural variation in abiotic conditions. Overall, the Ecophys.Fish model gave accurate field predictions of each sole species' growth rate and proved to be a useful tool for monitoring and assessment of habitat quality for juvenile sole.
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Growth variability of juvenile soles Solea Solea and Solea senegalensis, and comparison with RNA : DNA ratios in the Tagus estuary, Portugal
Journal of Fish Biology, 2006Co-Authors: Vanessa F. Fonseca, Catarina Vinagre, Henrique N. CabralAbstract:Growth variability and condition of juvenile soles Solea Solea and Solea senegalensis, were assessed through RNA : DNA estimates and compared to absolute growth rates. Higher mean cohort RNA : DNA ratios were observed for cohort I at the beginning of estuarine occurrence for both species (4·42 and 4·87, for S. Solea and S. senegalensis respectively). Despite different estuarine colonization habits, no significant differences were observed between RNA : DNA monthly variation for both sole species within the same year (P > 0·05 for 2003 and 2004). Juvenile S. senegalensis showed significant differences between RNA : DNA ratios obtained for the two nursery areas (P
M. Solé - One of the best experts on this subject based on the ideXlab platform.
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Metal concentrations and detoxification mechanisms in Solea Solea and Solea senegalensis from NW Mediterranean fishing grounds.
Marine pollution bulletin, 2013Co-Authors: R Siscar, A Torreblanca, A Palanques, M. SoléAbstract:The common sole, Solea Solea and the Senegalese sole, Solea senegalensis are two important commercial species that coexist in the NW Mediterranean Sea. The present field survey was designed to assess the role of kidney in metal handling and detoxification in the two sole species collected at six fishing grounds along the Catalan coast. Metallothionein (MT) and selenium (Se) were analysed in relation to toxic metal loads in kidney as potential protective mechanisms. Acetylcholinesterase (AChE) and lactate dehydrogenase (LDH) activities as well as lipid peroxidation (LP) levels were measured in several tissues as general markers of toxicity. AChE was measured in brain muscle and gills, LDH in plasma and LP in muscle and gills. The protective role of MT and Se was indicated by the positive correlations with Hg and Cd levels as well as with the high Se:Hg ratio, in a species-dependent way. Principal Component Analysis (PCA) considering all chemical and biomarker variables discriminated individuals collected at the different fishing grounds.
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Comparative analysis of selected biomarkers and pesticide sensitivity in juveniles of Solea Solea and Solea senegalensis
Environmental Science and Pollution Research, 2013Co-Authors: B. Sànchez-nogué, I. Varó, M. SoléAbstract:The common sole, Solea Solea (Linneus, 1758), and the Senegalese sole, Solea senegalensis (Kaup, 1858), are two important commercial species that coexist in the NW Mediterranean. In order to assess the species' ability to respond to chemical insults, a comparison of activities on enzymes involved in xenobiotic metabolism was carried out. Juveniles of both species were sampled in winter 2011 from the Ebro Delta region, and activities of selected enzymes such as acetylcholinesterase (AChE), carboxylesterase (CbE), ethoxyresorufin O -deethylase (EROD) and glutathione S -transferase (GST) were determined in several tissues. Lipid peroxidation (LP) levels in plasma were measured as a sign of oxidative stress. In vitro exposures to selected pesticides were contrasted, analysing AChE and CbE activities in several tissue homogenates. Overall, enzymatic activities were higher in S. Solea except for gill GST and CbE and kidney GST, while plasmatic LP levels were similar. In vitro contrasts revealed lower IC50 values for CbE activities in S. Solea , suggesting a greater buffer capacity of this enzyme to potentially reduce pesticide toxicity over AChE.
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comparative xenobiotic metabolism capacities and pesticide sensitivity in adults of Solea Solea and Solea senegalensis
Comparative Biochemistry and Physiology C-toxicology & Pharmacology, 2013Co-Authors: Samuel Koenig, Kevin Guillen, M. SoléAbstract:The measurement of enzymatic activities involved in xenobiotic biotransformation was carried out in adults of Solea Solea and Solea senegalensis. The hepatic enzymes analysed were cytochrome P450 (CYP) related activities using eight fluorometric substrates and carboxylesterases (CbE). The conjugating activities of glutathione S-transferase (GST) and UPD-glucuronosyltransferase (UDPGT) were also assessed. Specific mammalian inhibitors were used as diagnostic tools for related activities of CYP1A (α-naphthoflavone; αNF), CYP2B6 and CYP2C19 (ticlopidine) and CYP3A4 (ketoconazole). The in vitro sensitivity to organophosphorous pesticides (OP) was tested in the S10 homogenate of brain (acetylcholinesterase-AChE) and liver (CbE). Furthermore, the pesticide chlorpyrifos oxon (CLPO) was used to explore the OP sensitivity of CbE of both species in two subcellular fractions (microsomes and cytosol), using two substrates. Overall, only two parameters confirmed species differences: EROD and cytosolic CbE being significantly elevated (p < 0.05) in the common sole, S. Solea. A high inhibition of CYP1A related activities using several fluorometric substrates (ER, MR and CEC) after in vitro incubation with αNF confirmed all measure CYP1A1-related activities whereas ketoconazole was more specific for BFCOD (CYP3A4). Pesticide sensitivity was similar for brain AChE but hepatic CbE had a protective role that was species and pesticide dependent.