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The antiparasitic effect of matrine and oxymatrine, the main alkaloidal constituents of the roots of Sophora flavescens , on Cryptocaryon irritans in vitro and in vivo was investigated. Matrine and oxymatrine completely stopped all ciliary movements of C. irritans theronts in vitro. In vivo trials were first conducted with uninfected red sea bream, Pagrus major fed a commercial pellet feed modified to contain matrine or oxymatrine (0.1 or 0.5 g·kg − 1 ). The doses were determined by HPLC analysis of the water extract of the S. flavescens roots used in our study. After seven days on the experimental test feed, approximately 50,000 hatched theronts were added to each tank, and the fish were maintained on the experimental feed for three additional days. The matrine-treated feed demonstrated potent anti- C. irritans activity, with the number of parasites reduced by 58% in the 0.5 g·kg − 1 of matrine-fed group. The oxymatrine-treated feed also showed weaker anti- C. irritans activity compared to matrine. Therefore, the main anti- C. irritans activity of the water extract of S. flavescens was considered to be due to matrine. In an 80-day oral challenge trial with P. major , the fish in the group treated with matrine (0.5 g·kg − 1 feed) survived throughout the experimental period against the infestations of C. irritans , which contrasts with the 100% mortality seen in the control group. Furthermore, the number of parasites in the group treated with matrine was reduced by 35% as compared to the control group when C. irritans infected fish fed matrine-treated feed (0.5 g·kg − 1 ) for 3 days. These results suggested that matrine could be a useful therapeutic agent against the infestations of C. irritans . [ABSTRACT FROM AUTHOR]

Highlights: [•] We constructed perceptual maps of fish controlling for demographic differences. [•] We found great perceptual differences between the products considered. [•] Gender, age and education do not affect the perception of products. [•] Consumer residence affects the perception of farmed sea bass and sea bream. [•] We suggest focusing on the healthy aspects of blue fish during promotion campaigns. [ABSTRACT FROM AUTHOR]

Highlights: [•] Fish collagen bioactive peptides were encapsulated in phosphatidylcholine nanoliposomes. [•] Low liposome polydispersity and high entrapment efficiency were achieved. [•] Encapsulation preserved the biological activities of the collagen peptide fraction. [ABSTRACT FROM AUTHOR]

Abstract: Previously we have isolated a novel gelatinolytic serine proteinase, named G1, from the muscle and the plasma of red sea bream. In order to clarify the structure and function of G1, we cloned the full-length cDNA of G1 from the hepatopancreas of red sea bream. G1 cDNA encoded 633 amino acids with a secretory signal sequence at N-terminus, three epidermal growth factor-like domains, a kringle domain, and a trypsin-like serine protease domain. The active site residues of a serine proteinase were conserved in the serine protease domain of G1. The tissue distributions of the mRNA and gelatinolytic activity of G1 were investigated using RT-PCR and gelatin zymography, respectively. Its activity was detected in various tissues while the mRNA of it was strongly expressed in the hepatopancreas. These results suggest that G1 is synthesized in hepatopancreas and carried to the muscle, kidney, heart and ovary via the bloodstream in the red sea bream. The enzyme has a similar domain structure and tissue distribution to those of human hyaluronan binding protein 2 (HABP2) engaged in the extracellular matrix (ECM) turnover. Thus, it is suggested that G1 is identified as HABP2 and is possibly involved in ECM proteolysis of red sea bream. [Copyright &y& Elsevier]

Abstract: Facilitative glucose transporters (GLUT) are transmembrane transporter proteins involved in glucose transport across the plasma membrane. In fish, several GLUT mRNAs have been cloned, but to date there is no information about these transporters in the marine euryhaline teleost Sparus aurata. In the present study we obtained the complete coding sequence from S. aurata GLUT1 (saGLUT1), composed by 4483 bases, presenting a 79 to 95% identity with respect to other fish GLUT1 mRNAs. The analysis of the 5′ and 3′ UTRs showed the presence of several post-transcriptional regulatory elements. In addition, the effect on saGLUT1 mRNA expression of the osmotic acclimation to four different environmental salinities (5, 12, 40 and 55ppt), in gills, kidney, liver and brain, was studied. Changes in mRNA expression levels were detected in gills and brain, indicating that GLUT1 has an important role in these organs for osmotic acclimation in S. aurata. [Copyright &y& Elsevier]

Abstract: The study of thermal tolerance is the first step to understanding species vulnerability to climate warming. This work aimed to determine the upper thermal limits of various fish and crustaceans in a temperate estuarine ecosystem and an adjacent coastal area. Species were ranked in terms of thermal tolerance and intraspecific variability was evaluated. The method used was the Critical Thermal Maximum (CTMax). The CTMax was found to be higher for species typically found in thermally unstable environments, e.g. intertidal, supratidal, southern distributed species and species that make reproduction migrations because they are exposed to extreme temperatures. Subtidal, demersal and northern distributed species showed lower CTMax values because they live in colder environments. Species from different taxa living in similar habitats have similar CTMax values which suggests that they have evolved similar stress response mechanisms. This study showed that the most vulnerable organisms to sea warming were those that occur in thermally unstable environments because despite their high CTMax values, they live closer to their thermal limits and have limited acclimation plasticity. Among the demersal species studied, two sea-breams (Diplodus bellottii and Diplodus vulgaris) are potentially threatened by sea warming because their CTMax values are not far from the mean water temperature and they are already under thermal stress during current heat waves. [Copyright &y& Elsevier]

Reef-associated fishes can respond to changes in habitat structure and the nature of their response can change with different spatial scales of observation. A structured hierarchical mensurative sampling design was used to sample temperate reef fish assemblages in northeastern New Zealand at several spatial scales over 2 years. The three spatial scales examined were tens of meters (transects), hundreds to thousands of meters (sites) and hundreds of kilometers (locations). We tested the hypothesis that fish assemblages differed between kelp forest habitat (relatively dense stands of the kelp, Ecklonia radiata (C. Agardh) J. Agardh, median depth=13.5 m) and barrens habitat (rocky reef dominated by turfing and encrusting red algae and the grazing urchin, Evechinus chloroticus (Valenciennes), median depth=6.7 m). Recently developed multivariate techniques were used to test for and quantify multivariate variation at different spatial scales. There were significant effects of habitat on the spatial distribution of fish assemblages, characterised by greater abundances or frequencies of Parika scaber, Chromis dispilus, Trachurus novaezelandiae, Nemadactylus douglasii, Bodianus unimaculatus, Odax pullus and Pseudolabrus miles in kelp forest habitat, and greater abundances or frequencies of Notolabrus celidotus, Notolabrus fucicola, Girella tricuspidata, Coris sandageri, Chironemus marmoratus, Parma alboscapularis, Scorpis violaceus and Kyphosus sydneyanus in barrens habitat. Some of the more common species, including Upeneichthys lineatus, Scorpis lineolatus and Cheilodactylus spectabilis showed no strong consistent effects of these two differing habitats on their distributions. There was, however, a significant Habitat×Locations interaction: effects of habitat did not occur at all locations. Variability was highest at the scale of individual transects and variability from site to site and from location to location was comparable. Spatial variation was large compared to inter-annual variation, which was minimal, and spatial patterns were consistent in the 2 years examined. Further experiments, including manipulations, are required to understand what mechanisms and processes might be driving these patterns. This study, coupled with results from previous studies, suggests that there may be a dynamic inter-play between effects of habitat on fish and effects of fish on biogenic habitat, such as kelp forests. [Copyright &y& Elsevier]

Interferon regulatory factors ( irf s) are a family of genes that encode transcription factors with important roles in regulating the expression of Type I interferons (IFNs) and other genes associated with related pathways. irf s have multitudinous functions in growth, development and regulation of oncogenesis. In this study, three irf family members ( irf2 , irf7 , irf9 ) were identified and characterized in Megalobrama amblycephala at the mRNA and amino acid levels. M. amblycephala irf s share a high sequence homology with other vertebrate irf s. Constitutive expression levels of the three genes were detected (using qPCR) in all studied tissues: low to medium in kidney, gills, heart and muscle, and high in liver, spleen, intestine and blood. qPCR was also used to analyze the dynamic expression patterns of irf s in different embryonic development stages: irf2 is not activated during the embryonic development, whereas irf9 appears to play important roles around hatching and during the larval development. Transcripts of all three studied irfs were upregulated after stimulation by Aeromonas hydrophila bacterium in liver, spleen, head kidney and trunk kidney, whereas downregulation was observed in intestine and gills. The results show that these three irf s are likely to be important factors in the blunt snout bream immune system. They also provide a foundation for studying the origin and evolution of the innate immune system in the blunt snout bream. [ABSTRACT FROM AUTHOR]

Natural zeolites have been increasingly used in terrestrial animal and freshwater fish diets as a growth and health promoter, but few studies have considered marine fish. Therefore, this study was planned to investigate the effects of dietary zeolite (clinoptilolite) incorporation on growth, feed and nutrient utilizations, whole body composition, waste excretions, intestinal morphology, fillet iron (Fe) and aluminum (Al) accumulations in juvenile gilthead sea bream ( Sparus aurata ). In the experiment, zeolite was included at 0 (Z0, control), 10 (Z10), 20 (Z20), 30 (Z30) and 40 g/kg (Z40) in a commercial sea bream diet and fed to fish with an initial weight of about 9.1 g for 10 weeks. Dietary zeolite treatments had a significant increasing effect on final weight (linear, P=0.046; quadratic, P=0.002) and specific growth rate (SGR) (linear, P=0.057; quadratic, P=0.010). Feed conversion efficiencies (FCE) of fish were linearly improved (linear, P=0.013) whereas PER increased both linearly (linear, P=0.033) and quadratically (quadratic, P=0.005). Supplemental zeolite did not affect body moisture or lipid but there was a trend for an increase (linear, P<0.10) in ash and a quadratic trend in protein (P<0.10) were recorded. Increasing dietary zeolite levels increased liver Fe levels and led to a quadratic affect on fillet Al levels (P<0.05) but did not change liver Al or fillet Fe levels (P>0.10). No differences in ADCs for dry matter, protein and lipid were detected but ADCs for energy had a quadratic trend (P=0.068). A trend for a decrease in total and dissolved nitrogen (N) losses was detected as the level of zeolite increased in the diet (quadratic, P=0.071 and 0.089 respectively). Anterior intestinal folds and gut length did not change with increasing zeolite levels but posterior intestinal folds decreased (linear, P=0.013; quadratic, P=0.023) and gut index had a quadratic trend (P=0.081). Optimum dietary inclusion level of zeolite was estimated as 27.1 g/kg based on the maximization of SGR, PER and FCE values. [ABSTRACT FROM AUTHOR]

The effects of elevated CO 2 partial pressure ( p CO 2 ) on otolith calcification and on the coupling between somatic and otolith growth were investigated in juvenile gilthead sea bream Sparus aurata . Six-month old individuals were raised during seven weeks under four p CO 2 conditions set according to projected future ocean acidification scenarios. Body and otolith biometric parameters were measured throughout the experiment along with the otolith biomineralization monitored using a radiotracer technique based on 45 Ca incorporation. Sea bream exhibited somatic growth resilience to all treatments. In contrast, increased growth rate and shape complexity of otoliths were observed with a pH T drop from 8.1 to 7.5. Hypercalcification was observed under lowered pH, with a rate of calcium incorporation increasing by up to 18% between pH T 8.1 and pH T 7.7. This work highlighted an uncoupling of otolith and body growth of juvenile sea bream within 40 days at pH T 7.9 projected to be reached by the end of the century. As the otolith is an essential tool used in reconstructing fish life history, this work suggests that information resulting from otolith studies should be interpreted with caution with respect to the potential impacts that ocean acidification projected modifications could have on otolith biomineralization. [ABSTRACT FROM AUTHOR]

Volatile organic compound (VOC) profile was determined during storage of sea bream ( Sparus aurata ) fillets under air and Modified Atmosphere Packaging (MAP — CO 2 /O 2 /N 2 : 60/10/30) at 0, 5 and 15 °C. Microbiological, TVB-N (Total Volatile Base Nitrogen) and sensory changes were also monitored. Shelf-life of sea bream fillets stored under air was 14, 5 and 2 days (d) at 0, 5 and 15 °C respectively, while under MAP was 18, 8, and 2 d at 0, 5 and 15 °C respectively. At the end of shelf life, the total microbial population ranged from 7.5 to 8.5 log cfu/g. Pseudomonas spp. were among the dominant spoilage microorganisms in all cases, however growth of Brochothrix thermosphacta and Lactic Acid Bacteria (LAB) were favoured under MAP compared to air. TVB-N production was favoured at higher temperatures and under air compared to lower temperatures and MAP. TVB-N increased substantially from the middle of storage and its value never reached concentrations higher than 30–35 mg N/100 g, which is the legislation limit, making it a poor chemical spoilage index (CSI). A lot of alcohols, aldehydes, ketones and ethyl esters that were detected in the present study have been reported as bacterial metabolites, others as products of chemical oxidation while others as aroma constituents. VOCs such as 3-methylbutanal, acetic acid, ethanol, ethyl esters of isovaleric and 2-methylbutyric acids, 1-penten-3-ol, 1-octen-3-ol and cis-4-heptenal appeared from the early or middle stages and increased until the end of storage. From those only 3-methylbutanal, acetic acid, ethanol and the ethyl esters have been reported as microbial origin, making them potential CSI candidates of sea bream fillets. [ABSTRACT FROM AUTHOR]

Abstract: Settlement and recruitment are well known to have critical influences on the demography of most marine fishes. Few studies have compared processes like larval supply, settlement and recruitment of fishes between protected (i.e. in marine protected areas, MPAs) and unprotected conditions and little information is available about the potential influence of early life history traits (e.g. pelagic larval duration, PLD) on these processes. In the present study, using the white sea bream Diplodus sargus sargus as a model species in the south-western Adriatic Sea, we investigated: 1) potential differences in the densities of adults, settlers, recruits and 1-YOs (one year old specimens) within an MPA and in unprotected areas, at multiple spatial scales; 2) the existence of local relationships between densities of adults (i.e. spawners), settlers, recruits and 1-YOs; and 3) the possible relationships between PLD and density of settlers. Both in 2009 and 2010 the density of settlers was higher at sites down-current to the MPA and showed a significant variability at the scale of sites (kms). Density of recruits only revealed variability among sites (both in 2009 and 2010), while density of 1-YOs was variable at the scale of sites and was higher in protected condition in 2011, but not in 2010. No significant relationships were found between the densities of adults, settlers, recruits and 1-YOs at the site scale, nor between PLD and the density of settlers. Results suggest a possible decoupling in space between the sequential life history stages of fish (from settlers to 1-YOs) due to dispersal (through sea currents or active fish movements). Further study may help better understand the actual contribution of MPAs to larval supply and recruitment in both MPAs and adjacent sites. [Copyright &y& Elsevier]

Abstract: We purified and characterized Type I collagen from the scales of the Pacific saury (Cololabis saira) and compared it with collagen from other organisms. Subunit composition of C. saira collagen (2α1+α2) was similar to that of red sea bream (Pagrus major) and porcine collagen. C. saira collagen did not form a firm gel after neutralization of pH in solution. The temperature of denaturation (24–25°C) of C. saira collagen was slightly lower than that of P. major collagen (26–27°C). The contents of proline and hydroxyproline were lower in red sea bream and Pacific saury collagen than in porcine collagen. Circular dichroism spectra and Fourier-transformed infrared spectra showed that heat denaturation caused unfolding of the triple helices in all three collagens. [Copyright &y& Elsevier]

Abstract: The objective of this study was to evaluate the effects of partial fish meal replacement by a bioprocessed soy product (BS) in juvenile gilthead sea bream over the course of a 3-month trial. A diet with fish meal as the sole protein source (FM) was compared to diets with 20% (BS20), 40% (BS40) and 60% (BS60) of replacement. The effects of diets on growth performance, feed utilization, gut integrity, liver structure and immune status were evaluated. Weight gain, feed efficiency, daily growth index and specific growth rate decreased at the highest level of BS, while feed intake increased. In fish from BS40 and BS60 groups, indices indicating growth in response to protein intake such as protein efficiency ratio and protein productive value were decreased significantly. Body composition did not differ among groups for all parameters analysed. As far as non-specific immune response is concerned, spontaneous respiratory burst activity of blood significantly decreased at BS20 and BS40 groups, while stimulated activity did not indicate any significant change. Serum myeloperoxidase levels and total bacteriolytic activity of complement increased significantly at the highest dietary inclusion of BS, compared to the control group, while serum lysozyme levels did not indicate significant changes. Liver structure was not affected at any level, but some alterations in intestinal morphology were observed in the distal intestine mainly in the BS60 group. Overall, FM replacement by BS affected negatively gilthead sea bream growth performance at the 60% level, protein efficiency from the 40% level and affected some indicators of the immune response. [Copyright &y& Elsevier]

Abstract: This work reports the degradation of nitrogen compounds in a commercial marine Recirculating Aquaculture System (RAS) aimed at the culture of sea bream (Sparus aurata) and sea bass (Dicentrarchus labrax). The annual production of fingerlings is around 18 million and the process includes a drum filter and a biological treatment in order to enhance the water quality. Ammonia measurements at the inlet of the biological system showed that the concentration of this compound followed a diurnal pattern closely related to the feeding of the fingerlings; thus every day after feeding around 8am, the concentration of ammonia started increasing, it reached a maximum about 8h after feeding and then continued decreasing until the following morning. With regard to nitrite concentration, no significant differences were observed between the values measured at the inlet and the outlet of the biological system during the day, with an average concentration of this compound ranging between 0.08 and 3.66mg NO2 −Nl−1. A drawback of ammonia removal by means of nitrification is the subsequent increase of nitrate as the final product of ammonia oxidation in the culture system. The nitrate concentration in the biofilters inlet was found to fluctuate between 22.33 and 55.44mg NO3 −Nl−1 during the characterization period. Partial water exchange was needed during the day in order to minimize the water losses during fish handling and to keep the concentration of nitrate below the maximum allowable level of 46mg NO3 −Nl−1 due to production requirements in the hatchery under study. The ammonia degradation within the biological system, obtained by the ammonia measurements and comparison of the values at the inlet and outlet of the trickling filters has been fitted satisfactorily to ½-order/0-order kinetic expressions in good agreement with the results found in literature for laboratory and pilot plant studies. Rate constants k (1/2-order) =0.49g1/2 m−1/2 day−1 and k (0-order) =0.64gm−2 day−1, have been obtained in this study for commercial trickling biofilters. Thus, this work reports for the first time the kinetics of ammonia oxidation in trickling biofilters installed in a commercial recirculating aquaculture marine water system. These results will provide useful information for the design of an appropriately sized biofilter in order to optimize the water quality and reduce the need to exchange water in this activity. [Copyright &y& Elsevier]