Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 9.639
Filtrar
1.
J Exp Biol ; 224(8)2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-34415044

RESUMO

Archerfish down a variety of aerial prey from a range of distances using water jets that they adjust to the size and distance of their prey. We describe here that characteristic rapid fin maneuvers, most notably of the pectoral and pelvic fins, are precisely coordinated with the release of the jet. We discovered these maneuvers in two fish, the jets of which had been characterized in detail, that had been trained to shoot from fixed positions at targets at different heights and that remained stable during their shots. Based on the findings in these individuals, we examined shooting-associated fin movement in 28 further archerfish of two species that could shoot from freely chosen positions at targets at different heights. Slightly before the onset of the water jet, at a time when the shooter remains stable, the pectoral fins of all shooters switched from asynchronous low-amplitude beating to a synchronized rapid forward flap. The onset and duration of the forward and subsequent backward flap were robust across all individuals and shooting angles but depended on target height. The pelvic fins were slowly adducted at the start of the jet and stopped moving after its release. All other fins also showed a characteristic sequence of activation, some starting ∼0.5 s before the shot. Our findings suggest that shooting-related fin maneuvers are needed to stabilize the shooter, and that these maneuvers are an important component in the precise and powerful far-distance shooting in archerfish.


Assuntos
Nadadeiras de Animais , Perciformes , Animais , Fenômenos Biomecânicos , Peixes , Humanos , Movimento , Natação
2.
Gene ; 802: 145869, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34352298

RESUMO

Skeletal myoblasts are activated satellite cells capable of proliferation and differentiation. Studies on mammalian myoblast differentiation and myogenesis could be carried out in vitro thanks to the availability of mouse myoblast cell line C2C12. Lacking of muscle cell line hinders the studies of teleost fish myogenesis. Here, we established a continuous skeletal muscle cell line from juvenile rockfish (Sebastes schlegelii) muscle using explant method and subcultured more than 50 passages for over 150 days. Stable expression of myoblast-specific marker, MyoD (myoblast determination protein) and the potential of differentiation into multi-nucleated skeletal myotubes upon induction suggested the cell line were predominately composed of myoblasts. Transcriptome analysis revealed a total of 4375 genes differentially expressed at four time points after the switch to differentiation medium, which were mainly involved in proliferation and differentiation of myoblasts. KIF22 (kinesin family member 22) and POLA1 (DNA polymerase alpha 1) were identified as the key genes involved in fish myoblast proliferation whereas MYL3 (myosin light chain 3) and TNNT2 (troponin T2) were determined as the crucial genes responsible for differentiation. In all, the continuous myoblasts cultured in this study provided a cell platform for future studies on marine fish myoblast differentiation and myogenesis. The molecular process of myoblast differentiation revealed in this study will open a window into the understanding of indeterminate muscle growth of large teleost.


Assuntos
Técnicas de Cultura de Células , Linhagem Celular , Desenvolvimento Muscular/genética , Mioblastos Esqueléticos/fisiologia , Perciformes/anatomia & histologia , Animais , Criopreservação , Transcriptoma
3.
Mar Environ Res ; 170: 105452, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34433123

RESUMO

Contaminant Exposure Models (CEMs) were developed to predict population-level tissue contaminant concentrations in fishes by pairing sediment-bound contaminant concentrations (DDTs, PCBs) and fine-scale acoustic telemetry data from a habitat-associated species (Vermilion Rockfish, Sebastes miniatus), nomadic flatfish species (Hornyhead Turbot, Pleuronichthys verticalis), and nomadic benthic/midwater schooling species (White Croaker, Genyonemus lineatus) tagged near wastewater outfalls in southern California. Model results were compared to contaminant concentrations in tissue samples. The CEMs developed require further refinement before implementation into management efforts but may act as steppingstones to help shift primary monitoring methods away from the regular field collection of fish for tissue contaminant analyses and towards behavioral modeling and habitat mapping. We also developed Kernel Density Estimates that can be used by managers immediately to identify regions that contribute most to contaminant exposure in species of concern. Prioritizing remediation efforts in these areas are likely to be most effective at improving fish health.


Assuntos
Linguado , Perciformes , Poluentes Químicos da Água , Acústica , Animais , Monitoramento Ambiental , Telemetria , Águas Residuárias , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
4.
Biol Lett ; 17(8): 20210201, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34343439

RESUMO

In many species, males can rapidly adjust their ejaculate performance in response to changing levels of sperm competition, an ability that is probably mediated by seminal fluid adaptive plasticity. In the black goby, Gobius niger, territorial males attach viscous ejaculate trails to the nest roof, from which sperm are slowly released into the water during the long-lasting spawning events. Sneaker males release their sperm in the vicinity of the nest, and territorial males try to keep them at a distance by patrolling their territory. We show here that territorial males' ejaculate trails released a higher proportion of their sperm in the presence of a single sneaker, but this proportion decreased when there were three sneakers, an effect that is most likely mediated by a change in the seminal fluid composition. Field observations showed that when multiple sneaking attempts occurred, territorial males spent more time outside the nest, suggesting that ejaculation rate and territory defence are traded-off. Altogether, these results suggest that the adjustment of sperm release from the ejaculate may be strategic, guaranteeing a more continuous concentration of the territorial male's sperm in the nest, although at a lower level, when he is engaged in prolonged territory defence outside the nest.


Assuntos
Perciformes , Comportamento Sexual Animal , Animais , Masculino , Espermatozoides , Territorialidade
5.
Ecotoxicol Environ Saf ; 222: 112462, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34217113

RESUMO

Endocrine disrupting chemicals (EDCs) including 17ß-estradiol (E2) are widely distributed in the aquatic environment and are known to negatively affect the reproductive system of many animals, including fish. EDCs leading to feminization, altered sex ratio and reduced fecundity, it is possibly posing potential risks to the ecosystems. To investigate the potentially toxic effects of E2 exposure on little yellow croaker (Larimichthys polyactis, L. poliactis) who have a unique gonadal development pattern that males undergo a hermaphroditic stage. An experiment was set up where L. poliactis were maintained in tanks and exposed to E2 concentrations of 10 µg/L or no E2 exposure (the ethanol and control groups) from 30 to 90 days post-hatching (dph). After exposure, the E2 withdrawal and continual cultured to 150 and 365 dph. The morphological and histological analyses were used to compare the changes in the fish body and gonad under E2 exposure. The results showed that E2 exposure caused three major phenotypes at 30 and 60 days after treatment (dat), including ovary, ovotestis and gonadal development retardation compared with the control groups. The average ratio of these three phenotypes is 60.6%, 11.97% and 27.43%, respectively. The body length and weight of E2 exposure groups were repressed during the E2 exposure period, while it can recover after E2 withdrawal. However, the gonadal development (Gonadosomatic Index) of E2 exposure groups testis were retarded at 60 dat and doesn't recover until 365 dph. The sex determination/differentiation-related genes erα, erßI, erßII, fshß and cyp11b2 were significantly decreased in E2-exposure male fish. This research highlights the E2 leads to feminization, disrupts testis maturation and spermatogenesis, this effect persisted into the stage of sexual maturity. Collectively, our findings provide insights into the molecular mechanisms underlying E2 disturbance of a marine economic fish reproduction.


Assuntos
Estradiol , Perciformes , Animais , Ecossistema , Estrogênios , Feminino , Gônadas , Masculino
6.
Aquat Toxicol ; 237: 105848, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34274866

RESUMO

Control of invasive sea lamprey (Petromyzon marinus) in the Laurentian Great Lakes of North America uses lampricides, which consist of 3-trifluoromethyl-4-nitrophenol (TFM) and niclosamide. Lampricides are thought to inhibit aerobic energy synthesis, with TFM having a relatively greater selective action against lampreys. While the toxicity and physiological effects of TFM are known, the impacts associated with exposure to niclosamide and TFM:niclosamide mixtures are poorly characterized in fishes. Therefore, focusing on energy metabolism, we quantified the physiological responses of larval sea lamprey and bluegill (Lepomis macrochirus), a non-target, native species. Exposures consisted of each lampricide alone (TFM at the species-specific 24 h LC10; niclosamide at 1.5% of the mixture's TFM concentration) or a mixture of the two (larval sea lamprey at TFM 24 h LC10 + 1.5% niclosamide; bluegill at sea lamprey's TFM 24 h LC99.9 + 1.5% niclosamide) for 24 h. Tissues (brain, skeletal muscle, and liver) were sampled at 6, 12, and 24 h of exposure and assayed for concentrations of ATP, phosphocreatine, glycogen, lactate, and glucose and tissue lampricide levels. In larval sea lamprey, TFM had little effect on brain and skeletal muscle, but niclosamide resulted in a depletion of high energy substrates in both tissues. Mixture-exposed lamprey showed depletion of high energy substrates, accumulation of lactate, and high mortality rates. Bluegill were largely unaffected by toxicant exposures. However, bluegill liver showed lower glycogen and lactate under all three toxicant exposures suggesting increased metabolic turnover. Bluegill also had lower concentrations of TFM and niclosamide in their tissues when compared to lamprey. Our results indicate that lampricide toxicity in sea lamprey larvae is mediated through a depletion of high energy substrates because of impaired aerobic ATP synthesis. We also confirmed that non-target bluegill showed high tolerance to lampricide exposure, an effect potentially mediated through a high detoxification capacity relative to lampreys.


Assuntos
Perciformes , Petromyzon , Poluentes Químicos da Água , Animais , Lagos , Larva , Poluentes Químicos da Água/toxicidade
7.
Ultrason Sonochem ; 76: 105657, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34229120

RESUMO

This research evaluated the effects of multi-frequency ultrasound assisted freezing (UAF) on the freezing rate, structural characteristics, and quality properties of cultured large yellow croaker. The freezing effects with triple ultrasound-assisted freezing (TUF) at 20, 28 and 40 kHz under 175 W was more obvious than that of single ultrasound-assisted freezing (SUF) at 20 kHz and dual ultrasound-assisted freezing (DUF) at 20 and 28 kHz. The results showed that UAF significantly increased the freezing rate and better preserved the quality of frozen large yellow croaker samples. Specifically, the quality parameters of the TUF-treated samples were closer to those of the fresh samples, with greater texture characteristics, a larger water holding capacity (lower thawing loss and cooking loss), lower K values and lower thiobarbituric acid reactive substances values. Light microscopy observation images revealed that the ice crystals formed by TUF were fine and evenly distributed, resulting in less damage to the frozen large yellow croaker samples. Therefore, multi-frequency UAF could improve the quality properties of the large yellow croaker samples.


Assuntos
Qualidade dos Alimentos , Congelamento , Perciformes , Ondas Ultrassônicas , Animais
8.
Sci Total Environ ; 794: 148805, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34323774

RESUMO

The surrounding environments that animals inhabit shape their behavioral phenotypes, physiological status and molecular processes. As one of the driving forces for the adaptation and evolution of marine animals, environmental complexity has been shown to affect several behavioral characteristics in fish. However, little is known about the effects of environmental complexity on fish spatial cognition and about the relevant regulatory mechanisms. To address this theoretical gap, black rockfish Sebastes schlegelii, which is a typical rock fish species, were exposed to laboratory-based small-scale contrasting environments (i.e., spatially complex environment vs. spatially barren environment) for seven weeks. Subsequently, the spatial cognitive abilities and behavioral performance during captive period were determined, and transcriptome sequencing and analyses for fish telencephalon were conducted. In general, the fish from barren environment had significantly lower spatial learning and memory abilities compared with the fish from complex environment (i.e., the complex fish exited the maze faster). During the whole captive period, the frequency of aggressive behavior among barren fish was significantly higher than complex fish. And meanwhile, the group dispersion index of barren group was also significantly higher than complex group, which indicated that complex fish tended to distribute in a more homogeneous pattern than barren fish. Through transcriptomic analyses, a series of differentially expressed genes and pathways which may underpin the damaged effects of barren environment on fish spatial cognition were identified, and these genes mainly related to stress response, metabolism, organism systems and neural plasticity. However, no significant differences in growth performance, locomotor activity (indicated by swimming behavior and rotatory behavior) between treatments were detected. Based on these results, mechanisms in the levels of behavior and molecule were proposed to explain the environmental effects on fish cognition. This study may provide fundamental information for deeply understanding the environmental effects on marine animals.


Assuntos
Perciformes , Transcriptoma , Animais , Cognição , Peixes
9.
Dis Aquat Organ ; 145: 165-172, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34263731

RESUMO

Meagre Argyrosomus regius is a potential candidate for Mediterranean aquaculture diversification, although several health issues still represent important bottlenecks for its sustainable production, including systemic granulomatosis (SG). To evaluate the SG progression in meagre during a 10 mo period of cage ongrowing, a histopathological investigation was carried out on 108 meagre fed 3 different diets (commercial pellets, hydrated commercial pellets and defrosted sardines). Histological sections of the gills and visceral organs were examined and lesions referable to SG scored from 1-3 according to the severity of the granulomatosis. The kidney and liver were the most affected organs, showing the highest percentage of positivity for granulomas and severity of lesions along the whole observation period. Using a statistical mixed model (GLMM) followed by odds ratio analysis, an effect of diet and temperature was found: the severity of liver and digestive tract SG scores decreased in the Cage 3 group (defrosted sardines) and with increasing temperature (p < 0.05, negative estimates, odds ratio <1). These observations, in accordance with the literature, suggest that SG in meagre could be related to nutritional-metabolic factors with the possible influence of environmental factors such as temperature.


Assuntos
Perciformes , Animais , Aquicultura , Dieta/veterinária , Brânquias , Fígado
10.
Mol Ecol ; 30(17): 4259-4275, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34181798

RESUMO

Depth separation is a proposed driver of speciation in marine fishes, with marine rockfish (genus Sebastes) providing a potentially informative study system. Sebastes rockfishes are commercially and ecologically important. This genus encompasses more than one hundred species and the ecological and morphological variance between these species provides opportunity for identifying speciation-driving adaptations, particularly along a depth gradient. A reduced-representation sequencing method (ddRADseq) was used to compare 95 individuals encompassing six Sebastes species. In this study, we sought to identify regions of divergence between species that were indicative of divergent adaptation and reproductive barriers leading to speciation. A pairwise comparison of S. chrysomelas (black-and-yellow rockfish) and S. carnatus (gopher rockfish) FST values revealed three major regions of elevated genomic divergence, two of which were also present in the S. miniatus (vermilion rockfish) and S. crocotulus (sunset rockfish) comparison. These corresponded with regions of both elevated DXY values and reduced nucleotide diversity in two cases, suggesting a speciation-with-gene-flow evolutionary model followed by post-speciation selective sweeps within each species. Limited whole-genome resequencing was also performed to identify mutations with predicted effects between S. chrysomelas and S. carnatus. Within these islands, we identified important SNPs in genes involved in immune function and vision. This supports their potential role in speciation, as these are adaptive vectors noted in other organisms. Additionally, changes to genes involved in pigment expression and mate recognition shed light on how S. chrysomelas and S. carnatus may have become reproductively isolated.


Assuntos
Genoma , Perciformes , Adaptação Fisiológica , Animais , Deriva Genética , Especiação Genética , Humanos , Perciformes/genética , Filogenia
11.
Free Radic Biol Med ; 172: 213-225, 2021 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-34116177

RESUMO

Lipid overload-induced hepatic steatosis is a major public health problem worldwide. However, the potential molecular mechanism is not completely understood. Herein, we found that high-fat diet (HFD) or oleic acid (OA) treatment induced oxidative stress which prevented the entry of hepatocyte nuclear factor 4 alpha (HNF4α) into the nucleus by activating protein kinase C delta (PKCδ) in vivo and in vitro in large yellow croaker (Larimichthys crocea). This reduced the level of microsomal triglyceride transfer protein (MTP) transcription, resulting in the impaired secretion of very-low-density lipoprotein (VLDL) and the abnormal accumulation of triglyceride (TG) in hepatocytes. Meanwhile, the detrimental effects induced by lipid overload could be partly alleviated by pretreating hepatocytes with Go6983 (PKCδ inhibitor) or N-acetylcysteine (NAC, reactive oxygen species (ROS) scavenger). In conclusion, for the first time, we revealed that lipid overload impaired hepatic VLDL secretion via oxidative stress-mediated PKCδ-HNF4α-MTP pathway in fish. This study may provide critical insights into potential intervention strategies against lipid overload-induced hepatic steatosis of fish and human beings.


Assuntos
Lipoproteínas VLDL , Perciformes , Animais , Proteínas de Transporte , Hepatócitos/metabolismo , Humanos , Lipoproteínas VLDL/metabolismo , Fígado/metabolismo , Estresse Oxidativo , Perciformes/metabolismo
12.
Sci Total Environ ; 791: 148250, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34118674

RESUMO

Large reef-associated predatory fishes play important roles in aquatic ecosystem along coast because of their ecological functions and economic values to recreational and commercial fisheries. This study was carried out to assess the function of artificial reefs as alternative habitats for two common reef-associated predatory fishes in the north of Yellow Sea, China, Fat Greenling Hexagrammos otakii and Korean rockfish Sebastes schlegelii. According to the catch per unit effort (CPUE), the biomass of predatory fishes at the artificial reef was comparable (H. otakii) to or higher (S. schlegelii) than the natural reef, highlighting the environmental fitness of the artificial reef. Gut content analysis (GCA) showed that H. otakii preyed primarily on Decapod and Amphipoda, while S. schlegelii exhibited higher dependence on fish (Blinniidae and Gobiidae) and Decapod. Collectively, prey richness and diversity were greater at the natural reef relative to the artificial reef, and prey availability may be different between the two reef types. Stable isotopic analysis (SIA) in conjunction with the Bayesian mixing model (MixSIAR) revealed spatial and interspecific difference on the diet composition of H. otakii and S. schlegelii as well. Based on GCA and MixSIAR result, the habitat-specific effect on the prey availability was confirmed. Additionally, comparisons on trophic niche breadth and niche overlap indicated higher trophic diversity but relatively lower food resources partitioning degree for both species at the natural reef than at the artificial reef. Our results suggest that artificial reefs may harbor a different prey assemblage comparing to natural reef but can support large populations of predatory reef-associated fishes and accommodate their coexistence.


Assuntos
Ecossistema , Perciformes , Animais , Teorema de Bayes , China , Recifes de Corais , Peixes
13.
Fish Physiol Biochem ; 47(4): 1133-1147, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34059979

RESUMO

Hypoxia has gradually become common in aquatic ecosystems and imposes a significant challenge for fish farming. The loss of equilibrium (LOE), 50% lethal time (LT50), plasma cortisol, glucose, red blood cells (RBC), hemoglobin (Hb), gill histological alteration, and related parameters (lamellar length [SLL] and width [SLW], interlamellar distance [ID], basal epithelial thickness [BET], lamellar surface area [LA], and gill surface area [GSA]); respiratory rate; the proportion of the secondary lamellae available for gas exchange (PAGE); and hypoxia-inducible factor (hif-1α, hif-2α) mRNA expression were determined during progressive hypoxia and reoxygenation (R-0, R-12, R-24 h) to illustrate the underlying physiological response mechanisms in black rockfish Sebastes schlegelii. Results showed that the DO concentration significantly decreased during progressive hypoxia, while DO at LOE and LT50 were 2.42 ± 0.10 mg L-1 and 1.67 ± 0.38 mg L-1, respectively. Cortisol and glucose were significantly increased at LOE and LT50, with the highest levels observed at LT50, and then gradually recovered to normal within reoxygenation 24 h. RBC number and Hb results were like those of glucose. Hypoxia stress resulted in lamellar clubbing, hypertrophy, and hyperplasia. Respiratory frequency significantly increased at LOE and decreased at LT50. Lamellar perimeters, SLL, ID, LA, GSA, and PAGE, significantly increased at LOE and LT50, with the highest values observed at LT50. However, SLW and BET significantly decreased at LOE, LT50, and R-0. These parameters recovered to nearly normal levels at R-24 h. hif-1α mRNAs in gill and liver were significantly upregulated at LOE and LT50, and recovery to normal after reoxygenation 24 h. hif-2α mRNAs in gill was similar to that of hif-1α, whereas hepatic hif-2α mRNAs remained unchanged during hypoxia-reoxygenation. These results indicated that progressive hypoxia stress elevated RBC number, Hb, cortisol, and glucose levels, induced the alteration of gill morphology, increased LA and GSA, stimulated respiratory frequency and PAGE, and upregulated the transcription of hif-1α and hif-2α in gill and liver. Reoxygenation treatment for 24 h alleviated the stress mentioned above effects. These findings expand current knowledge on hypoxia tolerance in black rockfish Sebastes schlegelii.


Assuntos
Brânquias/patologia , Oxigênio , Perciformes/fisiologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Glicemia/análise , Contagem de Eritrócitos , Expressão Gênica , Brânquias/metabolismo , Hemoglobinas , Hidrocortisona/sangue , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Oxigênio/análise , Perciformes/anatomia & histologia , Perciformes/sangue , Perciformes/genética , Estresse Fisiológico/genética , Estresse Fisiológico/fisiologia
14.
Mar Pollut Bull ; 170: 112661, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34182302

RESUMO

There are many toxicological studies on microplastics, but little is known about the effect of nanoplastics (NPs). Here, we evaluated the oxidative stress responses induced by NPs (10, 104 and 106 particles/l) in juvenile Larimichthys crocea during 14-d NPs exposure followed by a 7-d recovery. After exposure, the activities of antioxidant enzymes (SOD, CAT, GPx) and MDA levels increased in the liver of fish at the highest NPs concentration. SOD and CAT activities remained elevated above the baseline after recovery under high-concentration NPs but returned to the baseline in two other NP treatments. Although lipid peroxidation in liver was reversible, juvenile fish in NPs treatments exhibited a lower survival rate than the control during both exposure and recovery. Furthermore, IBR value and PCA analysis showed the potential adverse effects of NPs. Considering that NPs can reduce the survival of fish juveniles, impacts of NPs on fishery productivity should be considered.


Assuntos
Microplásticos , Perciformes , Animais , Proteínas de Peixes/metabolismo , Fígado/metabolismo , Estresse Oxidativo , Perciformes/metabolismo , Plásticos/metabolismo
15.
Environ Pollut ; 284: 117449, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34098369

RESUMO

Plastics in the oceans can break up into smaller size and shape resembling prey or particles selected for ingestion by marine organisms. Plastic polymers may contain chemical additives and contaminants, including known endocrine disruptors that may be harmful for the marine organisms, in turn posing potential risks to marine ecosystems, biodiversity and food availability. This study assesses the presence of plastics in the contents of the gastrointestinal tract (GIT) of a commercial fish species, the Atlantic horse mackerel, Trachurus trachurus, sampled from two different fishing areas of central Mediterranean Sea. Adverse effect of plastics occurrence on T. Trachurus health were also assessed quantifying the liver expression of vitellogenin (VTG), a biomarker for endocrine disruption. A total of 92 specimens were collected and morphometric indices were analysed. A subgroup was examined for microplastics (MP < 1 mm) and macroplastics (MaP >1 cm) accumulation in the GIT and for VTG expression. Results indicated that specimens from the two locations are different in size and maturity but the ingestion of plastic is widespread, with microplastics (fragments and filaments) abundantly present in nearly all samples while macroplastics were found in the larger specimens, collected in one of the two locations. Spectroscopic analysis revealed that the most abundant polymers in MP fragments were polystyrene, polyethylene and polypropylene, whereas MP filaments were identified mainly as nylon 6, acrylic and polyester. MaP were composed mainly of weathered polyethylene or polypropylene. The expression of VTG was observed in the liver of 60% of all male specimens from both locations. The results of this study represent a first evidence that the ingestion of plastic pollution may alter endocrine system function in adult fish T. Trachurus and warrants further research.


Assuntos
Perciformes , Poluentes Químicos da Água , Animais , Ingestão de Alimentos , Ecossistema , Sistema Endócrino , Monitoramento Ambiental , Masculino , Mar Mediterrâneo , Plásticos , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
16.
Braz J Biol ; 83: e246180, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34190762

RESUMO

In fisheries, the phenomenon known as fishing down food webs is supposed to be a consequence of overfishing, which would be reflected in a reduction in the trophic level of landings. In such scenarios, the resilience of carnivorous, top predator species is particularly affected, making these resources the first to be depleted. The Serra Spanish mackerel, Scomberomorus brasiliensis, exemplifies a predator resource historically targeted by artisanal fisheries on the Brazilian coast. The present work analyzes landings in three periods within a 50-year timescale on the Parana coast, Southern Brazil, aiming to evaluate whether historical production has supposedly declined. Simultaneously, the diet was analyzed to confirm carnivorous habits and evaluate the trophic level in this region. Surprisingly, the results show that from the 1970's to 2019 Serra Spanish mackerel production grew relatively to other resources, as well as in individual values. The trophic level was calculated as 4.238, similar to other Scomberomorus species, consisting of a case where landings increase over time, despite the high trophic level and large body size of the resource. The results agree with a recent global assessment that has demystified a necessary correlation between high trophic level and overexploitation, but possible factors acting on the present findings are discussed.


Assuntos
Pesqueiros , Perciformes , Animais , Brasil , Conservação dos Recursos Naturais , Cadeia Alimentar
17.
Food Chem ; 362: 130159, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34167065

RESUMO

The sequential fractionation by supercritical-CO2 (SC-CO2) was applied to obtain fractions enriched in bioactive compounds of pomegranate peel, and we investigated if pomegranate peel extract and fractions would be effective to inhibit lipid and protein oxidation, and discolouration of bluefish patties stored at 4 °C for 9 days, after UV-C irradiation. The non-fractionated SC-CO2 extract from pomegranate peel was rich in phenolic compounds, mainly ellagitannins, besides, it possessed lipophilic compounds such as tocopherols and ß-carotene. These compounds were successfully separated by the fractionation protocols, in a lipid fraction concentrated in lipophilic compounds, and one or two fractions enriched with phenolic compounds, especially ellagitannins. The lipid fraction and the high phenolics fraction from pomegranate peel were then as effective as the synthetic antioxidant BHT in avoiding bluefish patties oxidation during refrigerated storage. Our data indicates that pomegranate peel fractions could be used to replace a synthetic antioxidant in fish meat.


Assuntos
Antioxidantes/química , Fracionamento Químico/métodos , Produtos Pesqueiros , Perciformes , Romã (Fruta)/química , Animais , Antioxidantes/análise , Dióxido de Carbono/química , Cor , Proteínas de Peixes da Dieta/química , Conservação de Alimentos/métodos , Frutas/química , Taninos Hidrolisáveis/análise , Lipídeos/química , Oxirredução , Fenóis/análise , Extratos Vegetais/química , Tocoferóis/análise , Raios Ultravioleta
18.
Fish Shellfish Immunol ; 115: 7-13, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34062236

RESUMO

Tumor necrosis factor receptor-associated factor 5 (TRAF5) is an intracellular protein that binds to the cytoplasmic portion of tumor necrosis factor receptors and mediates the activation of downstream nuclear factor-kappa B (NF-κB), interferon regulatory factor 3, and mitogen activated protein kinase signaling pathways. Compared with other TRAF proteins, TRAF5 is largely unknown in teleosts. In the present study, a TRAF5 homologue (HgTRAF5) from the hybrid grouper (Epinephelus fuscoguttatus♂ × Epinephelus lanceolatus♀) was cloned and characterized. The open reading frame of HgTRAF5 consists of 1743 nucleotides encoding a 581 amino acid protein with a predicted molecular mass of 64.90 kDa. Similar to its mammalian counterpart, HgTRAF5 contains an N-terminal RING finger domain, a zinc finger domain, and a C-terminal TRAF domain, including a coiled-coil domain and a MATH domain. HgTRAF5 shares 99.83% identity with giant grouper (Epinephelus lanceolatus) TRAF5. Quantitative real-time PCR analysis indicated that HgTRAF5 mRNA was broadly expressed in all examined tissues. The expression of HgTRAF5 increased after Singapore grouper iridovirus (SGIV) infection in grouper spleen (GS) cells. Intracellular localization analysis demonstrated that the full-length HgTRAF5 protein mainly distributed in the cytoplasm. HgTRAF5 overexpression also promoted SGIV replication during viral infection in vitro. HgTRAF5 significantly promoted the activities of interferon-ß, interferon-sensitive response element, and NF-κB. Taken together, these results are important for a better understanding of the function of TRAF5 in fish and reveal its involvement in the host response to immune challenge by SGIV.


Assuntos
Doenças dos Peixes/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Perciformes/genética , Perciformes/imunologia , Fator 5 Associado a Receptor de TNF/genética , Fator 5 Associado a Receptor de TNF/imunologia , Sequência de Aminoácidos , Animais , Bass , Infecções por Vírus de DNA/imunologia , Proteínas de Peixes/química , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Perfilação da Expressão Gênica/veterinária , Filogenia , Ranavirus/fisiologia , Alinhamento de Sequência/veterinária , Fator 5 Associado a Receptor de TNF/química
19.
Zootaxa ; 4991(3): 434-466, 2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34186835

RESUMO

Five new species of Stellifer are described from the Caribbean Sea and tropical southwestern Atlantic. Among the previously recognized stelliferine genera, Stellifer is unique by having a pair of variably developed appendages on the posterior margin of the anterior gas chamber, which is lacking in Bairdiella, Corvula, Elattarchus, Odontoscion and Ophioscion. However, recent genetic studies indicated that Stellifer and Ophioscion are not monophyletic. The genus Ophioscion Gill, 1863 is recognized herein as a junior synonym of Stellifer Oken, 1817. Of the five new species described, Stellifer cervigoni n. sp., S. collettei n. sp., and S. musicki n. sp. have a pair of knob-like diverticula along the posterior margin of the anterior gas chamber, which is absent in S. macallisteri n. sp., and S. menezesi n. sp. Stellifer cervigoni n. sp. is found along the southern Caribbean coast of Colombia and Venezuela; it can be distinguished from other species by having a jet-black roof of mouth and inner opercular lining. Stellifer collettei n. sp. is found from Surinam to southeastern Brazil, while S. musicki n. sp. is endemic to northern Brazil. Stellifer macallisteri n. sp. has an oblique, terminal mouth and it is found in Colombia, Venezuela and Dominican Republic. Stellifer menezesi n. sp. has a subterminal mouth and is found from northeastern to southeastern Brazil. These results bring the number of valid species of Stellifer in the Atlantic to 18, and a key to the identification of these species is included.


Assuntos
Perciformes/classificação , Animais , Oceano Atlântico , Brasil , Colômbia , República Dominicana , Venezuela
20.
Zootaxa ; 4974(1): 79115, 2021 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-34186868

RESUMO

Two species that had previously been referred to as Glossogobius giuris from Australia are redescribed and tentatively treated as Glossogobius giuris and Glossogobius laticeps. The two species are largely allopatric in Australia with G. laticeps found on the east coast of Queensland and some rivers of the Northern Territory, while G. giuris is distributed from the Northern Territory to rivers of the west coast of Western Australia. The two species are known to be genetically distinct and with some differences in colour patterns. Morphological features separating the species are minor and there is considerable overlap in many of the characters separating them. High variation in the Hammersley Ranges and Kimberley region of Western Australia further complicates separation of the species. The status of the Glossogobius giuris group from India is discussed as a key area to resolving an overall "giuris" species complex. Information is provided on the current identity of a number of species that had previously been considered synonyms of Glossogobius giuris. Extant types and difficulties assigning the types of known species are also discussed. A key is provided to aid identification of Australian species of Glossogobius.


Assuntos
Perciformes/classificação , Animais , Austrália
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...