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1.
Environ Pollut ; 266(Pt 2): 115376, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32829125

RESUMO

Motorboats are a pervasive, growing source of anthropogenic noise in marine environments, with known impacts on fish physiology and behaviour. However, empirical evidence for the disruption of parental care remains scarce and stems predominantly from playback studies. Additionally, there is a paucity of experimental studies examining noise-mitigation strategies. We conducted two field experiments to investigate the effects of noise from real motorboats on the parental-care behaviours of a common coral-reef fish, the Ambon damselfish Pomacentrus amboinensis, which exhibits male-only egg care. When exposed to motorboat noise, we found that males exhibited vigilance behaviour 34% more often and spent 17% more time remaining vigilant, compared to an ambient-sound control. We then investigated nest defence in the presence of an introduced conspecific male intruder, incorporating a third noise treatment of altered motorboat-driving practice that was designed to mitigate noise exposure via speed and distance limitations. The males spent 22% less time interacting with the intruder and 154% more time sheltering during normal motorboat exposure compared to the ambient-sound control, with nest-defence levels in the mitigation treatment equivalent to those in ambient conditions. Our results reveal detrimental impacts of real motorboat noise on some aspects of parental care in fish, and successfully demonstrate the positive effects of an affordable, easily implemented mitigation strategy. We strongly advocate the integration of mitigation strategies into future experiments in this field, and the application of evidence-based policy in our increasingly noisy world.


Assuntos
Ruído , Perciformes , Animais , Recifes de Corais , Peixes , Masculino
2.
Aquat Toxicol ; 226: 105568, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32791376

RESUMO

An emerging Multi-Ion Toxicity (MIT) model for assessment of environmental salt pollution is based on the premise that major ion toxicity to aquatic organisms is related to a critical disturbance of the trans-epithelial potential across the gills (ΔTEP), which can be predicted by electrochemical theory. However, the model has never been evaluated physiologically. We directly tested key assumptions by examining the individual effects of eight different salts (NaCl, Na2SO4, MgCl2, MgSO4, KCl, K2SO4, CaCl2, and CaSO4) on measured TEP in three different fish species (fathead minnow, Pimephales promelas = FHM; channel catfish, Ictalurus punctatus = CC; bluegill, Lepomis macrochirus = BG). A geometric concentration series based on previously reported 96-h LC50 values for FHM was used. All salts caused concentration-dependent increases in TEP to less negative/more positive values in a pattern well-described by the Michaelis-Menten equation. The ΔTEP responses for different salts were similar to one another within each species when concentrations were expressed as a percentage of the FHM LC50. A plateau was reached at or before 100 % of the LC50 where the ΔTEP values were remarkably consistent, with only 1.4 to 2.2-fold variation. This relative uniformity in the ΔTEP responses contrasts with 28-fold variation in salt concentration (in mmol L-1), 9.6-fold in total dissolved solids, and 7.9-fold in conductivity at the LC50. The Michaelis-Menten Km values (salt concentrations causing 50 % of the ΔTEPmax) were positively related to the 96-h LC50 values. ΔTEP responses were not a direct effect of osmolarity in all species and were related to specific cation rather than specific anion concentrations in FHM. These responses were stable for up to 24 h in CC. The results provide strong physiological support for the assumptions of the MIT model, are coherent with electrochemical theory, and point to areas for future research.


Assuntos
Cyprinidae/fisiologia , Epitélio/fisiologia , Brânquias/efeitos dos fármacos , Potenciais da Membrana/efeitos dos fármacos , Perciformes/fisiologia , Sais/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Eletrodos , Brânquias/fisiologia , Concentração Osmolar
3.
Rev Bras Parasitol Vet ; 29(3): e001620, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32638834

RESUMO

More than 1.450 marine fish species are commercialized as ornamental fish and approximately 90% of these are wild-caught. Rainford's butterflyfish, Chaetodon rainfordi (McCulloch, 1923), is endemic to the western Pacific. This fish species belongs to one of the main ornamental fish families imported into Brazil. Haliotrema is a genus of the family Dactylogyridae. Species of this genus have very interesting host associations and geographic distributions. The aim of this study was to report on occurrences of exotic Haliotrema aurigae in diseased Rainford butterflyfish that were imported to Brazil. One Rainford's butterflyfish with suspected parasitic disease was euthanized and subjected to skin and gill scraping. The parasite specimens were mounted on semi-permanent slides with Hoyer's solution for morphological analysis of sclerotized structures. The hard-sclerotized structures of these specimens were compared and were identified as those of Haliotrema aurigae (Yamaguti, 1968). These results emphasize the importance of implementation of correct control measures at the country's borders, to avoid the introduction of exotic parasites. In addition, it can be emphasized that the easy adaptation of this parasite to new environments is a concern for ornamental fish farmers.


Assuntos
Doenças dos Peixes , Perciformes , Trematódeos , Animais , Ásia , Brasil , Doenças dos Peixes/parasitologia , Espécies Introduzidas , Oceano Pacífico , Perciformes/parasitologia , Trematódeos/anatomia & histologia , Trematódeos/fisiologia
4.
Proc Biol Sci ; 287(1930): 20201133, 2020 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-32635871

RESUMO

A central issue in evolutionary ecology is how patterns of dispersal influence patterns of relatedness in populations. In terrestrial organisms, limited dispersal of offspring leads to groups of related individuals. By contrast, for most marine organisms, larval dispersal in open waters is thought to minimize kin associations within populations. However, recent molecular evidence and theoretical approaches have shown that limited dispersal, sibling cohesion and/or differential reproductive success can lead to kin association and elevated relatedness. Here, we tested the hypothesis that limited dispersal explains small-scale patterns of relatedness in the pajama cardinalfish Sphaeramia nematoptera. We used 19 microsatellite markers to assess parentage of 233 juveniles and pairwise relatedness among 527 individuals from 41 groups in Kimbe Bay, Papua New Guinea. Our findings support three predictions of the limited dispersal hypothesis: (i) elevated relatedness within groups, compared with among groups and elevated relatedness within reefs compared with among reefs; (ii) a weak negative correlation of relatedness with distance; (iii) more juveniles than would be expected by chance in the same group and the same reef as their parents. We provide the first example for natal philopatry at the group level causing small-scale patterns of genetic relatedness in a marine fish.


Assuntos
Perciformes/fisiologia , Dinâmica Populacional , Distribuição Animal , Animais , Recifes de Corais , Peixes , Repetições de Microssatélites , Papua Nova Guiné
5.
Aquat Toxicol ; 226: 105566, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32682194

RESUMO

Cytochrome P450 (CYP) enzymes play important roles in the detoxification and bioactivation of environmental contaminants and are involved in the responses to pollution in fish. In this study, we cloned four new CYP1 genes, CYP1A, CYP1B, CYP1C1, and CYP1C2, from black rockfish (Sebastes schlegelii), a dominant and economically important fish species in Korea. This species is at a significant risk of exposure to petrohydrocarbons, such as benzo[a]pyrene(B[a]P), due to frequent oil spills along the Korean coast. Quantitative PCR analysis of CYP1 gene transcription in 12 organs of the fish revealed tissue-specific expression patterns. CYP1A was significantly expressed in the liver, heart, kidneys, and muscle, and CYP1B was significantly expressed in the gills, muscle, and heart. CYP1C1 and CYP1C2 showed similar tissue expression patterns, with the highest levels in the muscle. Furthermore, exposure to an aryl hydrocarbon receptor (AHR) agonist, B[a]P, at 2, 20, and 200 mg/kg body weight showed significant dysregulation of the CYP1A, CYP1B, CYP1C1, and CYP1C2 expression levels in the gills, liver, kidneys, and spleen. The mRNA expression levels of CYP1A and CYP1B were upregulated by 450- and 17-fold, respectively, in the spleen. Compared with their levels in the control, CYP1C1 increased by 45-fold, while CYP1C2 remained unchanged in the gills, indicating differential effects of the polycyclic aromatic hydrocarbon on CYP1 expression in different fish organs. The results suggested that expression profiles of inducible CYP1 enzymes in S. schlegelii might be used as indicators for assessing aquatic contamination by AHR agonists. Determination of the basal and induced expression levels, as well as substrate specificity, of the four CYP1 enzymes may contribute to a better understanding of their roles in the metabolization of toxicants or drugs.


Assuntos
Benzo(a)pireno/toxicidade , Citocromo P-450 CYP1A1/metabolismo , Expressão Gênica/efeitos dos fármacos , Perciformes/metabolismo , Poluentes Químicos da Água/toxicidade , Animais , Citocromo P-450 CYP1A1/genética , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Perciformes/genética , Perciformes/crescimento & desenvolvimento , Receptores de Hidrocarboneto Arílico/metabolismo , República da Coreia
6.
PLoS Pathog ; 16(7): e1008670, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32678830

RESUMO

Increasing evidence suggests important roles for long noncoding RNAs (lncRNAs) as new gene modulators involved in various biological processes. However, the function roles of lncRNAs in lower vertebrates are still unknown. Here, we firstly identify a lncRNA, named MAVS antiviral-related lncRNA (MARL), as a key regulator for antiviral immunity in teleost fish. The results indicate that fish MAVS play essential roles in host antiviral responses and inhibition of Siniperca chuatsi rhabdovirus (SCRV) replication. miR-122 reduces MAVS expression and suppress MAVS-mediated antiviral responses, which may help viruses evade host antiviral responses. Further, MARL functions as a competing endogenous RNA (ceRNA) for miR-122 to control protein abundance of MAVS, thereby inhibiting SCRV replication and promoting antiviral responses. Our data not only shed new light on understanding the function role of lncRNA in biological processes in lower vertebrates, but confirmed the hypothesis that ceRNA regulatory networks exist widely in vertebrates.


Assuntos
MicroRNAs/metabolismo , Perciformes/imunologia , RNA Longo não Codificante/imunologia , Infecções por Rhabdoviridae/imunologia , Animais , Regulação para Baixo , Perciformes/virologia , Rhabdoviridae/imunologia
7.
Food Chem ; 332: 127373, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32619941

RESUMO

In the present study, effects of riboflavin (RF) and kelp polyphenol extracts (KPE) on mackerel (Scomberomorus Niphonius) myofibrillar protein (MP) gel were studied with or without ultraviolet A (UVA) irradiation treatment. The gel strength was increased with the addition of RF and KPE under UVA irradiation. Analysis of the proteins in the gel indicated that the carbonyl content increased, while the contents of total sulfhydryl and amino groups decreased. The proteins appeared to have no α-helix structures, and the endogenous tryptophan content appeared to decrease. The results of SDS-PAGE indicated that the RF and KPE treated samples under UVA irradiation showed massive MP cross-linking by covalent bonds. Electron spin resonance (ESR) results indicated that UVA irradiation generated free radicals in RF and KPE, which ultimately led to an improvement in MP gel properties. It also indicated that KPE could prevent the occurrence of peroxidation to improve the gel properties.


Assuntos
Proteínas de Peixes/química , Kelp/química , Perciformes , Polifenóis/química , Riboflavina/química , Raios Ultravioleta , Animais , Radicais Livres/química , Géis
8.
Dis Aquat Organ ; 140: 47-54, 2020 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-32614330

RESUMO

Healthy and/or moribund farmed and wild ballan wrasse Labrus bergylta (>0.5 to 900 g) were sampled from hatcheries (n = 2) and Atlantic salmon Salmo salar cage sites (n = 8) in Scotland between February 2016 and October 2018. Less than half of the sampled individuals (n = 43; 32.3%) had been vaccinated (autogenous polyvalent vaccine; dip and/or injection) against atypical furunculosis (type V and VI), while 20 (15.0%) fish were not vaccinated, and the rest (70 individuals, 52.7%) were of unknown vaccination status. Swab samples from skin lesions, gill, liver, spleen and kidney were inoculated onto a variety of bacteriological agar plates, and bacteriology identification and sequencing analysis was performed on significant bacterial colonies. Atypical Aeromonas salmonicida (aAs) vapA type V was the predominant bacterial species (70/215 bacterial isolates, 32.5% of bacterial samples; 43/117 positive individual fish, 36.8%) isolated in this survey followed by Vibrio species, which were the most geographically prevalent bacteria. Photobacterium indicum/profundum was also isolated from L. bergylta for the first time during this study. The collection of these bacterial isolates provides useful information for disease management. Identifying the aAs isolates involved in disease in ballan wrasse could provide vital information for improving/updating existing autogenous vaccines.


Assuntos
Aeromonas salmonicida , Doenças dos Peixes , Infecções por Bactérias Gram-Negativas/veterinária , Perciformes , Vibrioses/veterinária , Vibrio , Animais , Photobacterium , Escócia
9.
Dis Aquat Organ ; 140: 55-72, 2020 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-32614331

RESUMO

Amoebic gill disease (AGD), caused by the marine amoeba Paramoeba perurans, is an important disease of farmed Atlantic salmon Salmo salar L. in Norway. The use of wrasse as cleaner fish in salmon net pens raises questions about interspecies transmission of pathogens such as P. perurans. In this study, cohabitant transmission of clonal isolates of P. perurans between Atlantic salmon and ballan wrasse Labrus bergylta Ascanius was examined, using isolates originating from both salmon and wrasse. The challenges resulted in AGD in both species, although less severely in wrasse. The amoeba isolate originating from ballan wrasse was more virulent than that originating from salmon, suggesting P. perurans strain-related virulence differences. The isolate originating from salmon showed limited proliferation in bath-challenged wrasse and salmon, and limited transfer to cohabitants. Our results support previous observations suggesting that salmon may be more susceptible to P. perurans and AGD than ballan wrasse. Treatment of P. perurans infection in wrasse is challenging, as it is a strictly marine fish species. In this study, brackish water (<15‰ seawater) treatment of AGD affected salmon and wrasse was examined. Both salmon and wrasse were treated for short periods (3 h and 24 h), and treatment of wrasse over longer periods (3-5 d) was also examined. Short exposure to brackish water was not enough to remove P. perurans, although the 24 h treatment reduced amoeba levels. It was not possible to culture or detect P. perurans from wrasse exposed to brackish water for 3 d, suggesting that this treatment would be effective in controlling the parasite.


Assuntos
Amebíase/veterinária , Doenças dos Peixes , Perciformes , Salmo salar , Animais , Brânquias , Noruega
10.
Dis Aquat Organ ; 140: 13-24, 2020 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-32618284

RESUMO

Isopodiosis in cultured meagre Argyrosomus regius was investigated at 3 farms in the northern lakes of Egypt throughout 2018, based upon prevalence rate, parasitological examination, and molecular identification by PCR targeting the large ribosomal subunit 16S of the rRNA gene. Further, the susceptibility of A. regius to isopod infection was experimentally evaluated under hyposalination of 25, 15, and 8 ppt for 1 wk. The isolated isopod stages were morphologically identified as Livoneca redmanii Leach, 1818 with prevalence rates of 77.05 and 77.9% in Al-Madiyyah and Sidi Krir, respectively. The highest prevalence and salinity of 78.85% and 30-34 ppt were reported in El Matareya. DNA sequencing and molecular analysis confirmed the identification of L. redmanii. A. regius experimentally infected with L. redmanii under a hyposalination protocol at 15 and 8 ppt showed marked reduction in mortality (20 and 50%, respectively), and infection prevalence (40 and 63.33%, respectively). The serum lysozyme concentration and nitric oxide of treated fish at 15 and 8 ppt were significantly increased compared to those held at 25 and 33 ppt, whereas serum osmolality levels were higher at 25 and 33 ppt. To our knowledge, this is the first molecular characterization of L. redmanii in cultured A. regius in Egypt.


Assuntos
Isópodes , Perciformes , Animais
11.
Mar Pollut Bull ; 157: 111162, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32658660

RESUMO

Previous laboratory feeding experiments, representing the state-of-the-art methodology to investigate microplastic (MP) ingestion and its impact for fish, tend to disregard both the significance of applying realistic MP densities and the potential relevance of biofilm-coating for ingestion probability. This experiment assessed the uptake of either pristine or biofilm-coated MP particles and the physiological impacts for juvenile white seabream for MP concentrations consistent with those found in the field along with natural prey over a course of 3.5 weeks. Results indicate the ability of juvenile D. sargus to discriminate between edible and non-edible prey. A distinct preference for biofilm-coated over pristine particles could not be verified. No significant impact on growth and condition was found except for high levels of MP ingestion. The outcomes highlight the importance of performing MP feeding experiments mimicking natural conditions to reliably assess the impact of MP on early life stages of fish.


Assuntos
Perciformes , Dourada , Animais , Microplásticos , Plásticos
12.
An Acad Bras Cienc ; 92(2): e20190161, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32578665

RESUMO

Trichiurus lepturus (Actinopterygii, Perciformes) is a commercially and economically important fish. A total of 60 specimens of this cutlassfish were collected of the coast the municipalities of Niterói and Cabo Frio, state of Rio de Janeiro, Brazil. The fish were measured, necropsied, filleted and had their organs investigated for digenetic trematodes. Taxonomic identification was based on morphological and morphometric characters. The specimens of T. lepturus were parasitized with adult specimens of Lecithochirium monticellii. Parasite indices of prevalence, intensity, mean intensity, abundance, mean abundance, range of infection, and site of infection of parasitic species were evaluated. Notes on the taxonomy of the parasite were also included. This is the first report of L. monticellii parasitizing T. lepturus in Brazil.


Assuntos
Perciformes , Trematódeos , Animais , Brasil , Peixes
13.
Parasitol Res ; 119(7): 2139-2147, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32476061

RESUMO

Coccidian parasites of fish have received considerably less attention than their terrestrial counterparts, and within piscine hosts, most studies have focused on freshwater fish. The present study aimed to describe oocyst morphology, phylogenetic affinities, and the impacts of coccidian parasites infecting the internal organs of a commercially valuable marine fish, the blue whiting (Micromesistius poutassou), captured off the Portuguese coast. As part of the phylogenetic analysis, sequences from coccidians infecting the pout (Trisopterus luscus) and the Atlantic chub mackerel (Scomber colias) were included, and the oocyst morphology of the coccidians infecting the former was also reported. Results showed that the prevalence of coccidiosis in the blue whiting was very high (> 82%), occurring in all analyzed organs, despite being more abundant in the liver. A significant negative correlation was found between the abundance of the parasites in the liver and host condition index (p < 0.05), which indicates a negative effect on the fitness of this host. Phylogenetic analyses of the parasites found in all three species examined identified three different species of Goussia, closely related to Goussia clupearum. Adding to previous research, we propose the existence of a fourth group of Goussia, the clupearum type, able to infect multiple organs and phylogenetic related with G. clupearum.


Assuntos
Coccidiose/veterinária , Eimeriidae/classificação , Eimeriidae/patogenicidade , Doenças dos Peixes/parasitologia , Gadiformes/parasitologia , Animais , Coccidiose/parasitologia , Eimeriidae/citologia , Eimeriidae/genética , Fígado/parasitologia , Oocistos/classificação , Oocistos/citologia , Oocistos/genética , Perciformes/parasitologia , Filogenia , Portugal , Alimentos Marinhos/parasitologia
14.
Environ Sci Pollut Res Int ; 27(29): 36799-36815, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32572740

RESUMO

The objective of this study was to determine how the short-term exposure to a supraphysiological concentration of waterborne 17ß-estradiol (E2) influences on melatonin (Mel) and thyroxine (T4) concentrations in plasma and E2 and 11-ketotestosterone (11-KT) concentrations in plasma and gonads in both sexes of round goby (Neogobius melanostomus) during the pre-spawning, spawning, late spawning and non-spawning phases. The experimental protocol was based on short-term, repeated exposures of fish to a supraphysiological dose of waterborne E2. Mel level was unchanged on exposure to E2 during the investigated phases, and its role in determining a time frame for spawning in both sexes of round goby seems to be stable in those conditions. T4 and sex steroids (E2 and 11-KT) were sensitive to the exposure of E2, and those changes influence gonads by accelerating oocyte development, ovulation and regression and inhibiting spermatogenesis in this species. The results demonstrate that the physiological responses of fish in all investigated phases were altered over a short window of exposure, indicating that short-term exposure to a supraphysiological dose of E2 may impact fish in the wild. Furthermore, round goby can be recommended as a very suitable model for studying endocrine disruptors, which is sensitive to even short exposure to E2.


Assuntos
Estradiol , Perciformes , Animais , Estrogênios , Feminino , Peixes , Gônadas , Masculino
15.
PLoS One ; 15(6): e0234083, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32569296

RESUMO

Globally, rising temperatures have resulted in numerous examples of poleward shifts in species distribution patterns with accompanying changes in community structure and ecosystem processes. In the Gulf of Mexico, higher mean temperatures and less frequent winter freezes have led to the expansion of tropics-associated marine organisms. Our objectives were to quantify changing environmental conditions and the poleward expansion of the common snook Centropomus undecimalis into the Cedar Keys area of Florida, USA (29 deg N). The snook is an economically and recreationally important sport fish found from southern Brazil to south Florida. Cedar Key and the Lower Suwannee River are north of the snook's historically documented range, likely due to lethal water temperatures during winter. Using data from a long-term monitoring program, we report an increase in catches of snook in this area since 2007. The spatial and temporal expansion of the species began with adult fish in 2007. By 2018, snook of all sizes were found in the region, and we found strong evidence of local reproduction during 2016-2018. The locations of nursery habitat and winter thermal refuges (e.g., freshwater springs) need to be identified and have implications for land-use policy and minimum-flow regulations for rivers. The arrival of the snook in the northern Gulf of Mexico could affect food web ecology and habitat interactions among estuarine predators, and future studies should evaluate snook's food habits and competitive interactions with resident fishes in this expanded range. Our study provides an example of how species range expansions due to changing temperatures should result in new research priorities to evaluate impacts of climate change on coastal systems.


Assuntos
Ecossistema , Perciformes/crescimento & desenvolvimento , Animais , Mudança Climática , Cadeia Alimentar , Golfo do México , Estações do Ano
16.
Proc Biol Sci ; 287(1929): 20200239, 2020 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-32576103

RESUMO

Animals display remarkable variation in social behaviour. However, outside of rodents, little is known about the neural mechanisms of social variation, and whether they are shared across species and sexes, limiting our understanding of how sociality evolves. Using coral reef butterflyfishes, we examined gene expression correlates of social variation (i.e. pair bonding versus solitary living) within and between species and sexes. In several brain regions, we quantified gene expression of receptors important for social variation in mammals: oxytocin (OTR), arginine vasopressin (V1aR), dopamine (D1R, D2R) and mu-opioid (MOR). We found that social variation across individuals of the oval butterflyfish, Chaetodon lunulatus, is linked to differences in OTR,V1aR, D1R, D2R and MOR gene expression within several forebrain regions in a sexually dimorphic manner. However, this contrasted with social variation among six species representing a single evolutionary transition from pair-bonded to solitary living. Here, OTR expression within the supracommissural part of the ventral telencephalon was higher in pair-bonded than solitary species, specifically in males. These results contribute to the emerging idea that nonapeptide, dopamine and opioid signalling is a central theme to the evolution of sociality across individuals, although the precise mechanism may be flexible across sexes and species.


Assuntos
Expressão Gênica , Perciformes/fisiologia , Comportamento Social , Animais , Recifes de Corais , Perciformes/genética , Telencéfalo , Vasopressinas
17.
Parasitol Res ; 119(8): 2463-2471, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32529296

RESUMO

Members of the genus Sphaeromyxa Thélohan, 1892 have been reported from a wide variety of fish species worldwide. In the present study, specimens of rusty blenny, Parablennius sanguinolentus, collected from Sinop on the Turkish Black Sea coast were investigated for myxosporean parasites by using both conventional and molecular methods. Sphaeromyxa sevastopoli Naidenova 1970 was the only myxosporean parasite found in the gall bladder of host fishes. The morphology peculiarities of obtained S. sevastopoli spores are in good agreement with those of original description and the morphometric data overlapped in spore length and width but differed in polar capsule length and width; however, they were within the ranges previously reported from 18 host fish species. Moreover, in the present study, molecular analysis of the 18S rDNA gene of S. sevastopoli isolate in our P. sanguinolentus as well as isolates from shore rockling Gaidropsarus mediterraneus and knout goby Mesogobius batrachocephalus which were previously morphologically identified and reported by Okkay and Özer (Acta Zool Bulg 72(1):123-130, 2020) was done for the first time and our three S. sevastopoli genotypes were allocated to the "balbianii" group which is characterized by straight or slightly curved and fusiform or ovoid spores with ovoid polar capsules.


Assuntos
Cnidários/anatomia & histologia , Cnidários/genética , Doenças dos Peixes/parasitologia , Doenças Parasitárias em Animais/parasitologia , Perciformes/parasitologia , Animais , Mar Negro , Cnidários/classificação , DNA Ribossômico/genética , Vesícula Biliar/parasitologia , Especificidade da Espécie , Turquia
18.
Mar Pollut Bull ; 158: 111214, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32568074

RESUMO

Microplastics (<5 mm) are present in marine ecosystems worldwide where they can be ingested by a wide range of organisms from different trophic levels. In this study we analyzed the gastrointestinal tract of 443 specimens of Stellifer brasiliensis (124 juveniles, 254 subadults, and 65 adults) sampled in tropical beaches adjacent to the Paraíba River estuary. We found 1-3 microplastics in 42 fishes (9.48%), averaging 1.31 ± 0.52 microplastics per fish. The number of ingested microplastics by the different ontogenetic stages was statistically similar, but the adults had a higher ingestion frequency (13.8%). Among subadults, the condition factor of fishes that ingested microplastics was significantly smaller (p < 0.05) than those that had not ingested them. The ingestion of microplastics by the different ontogenetic stages of S. brasiliensis reflects the availability of this pollutant in the studied environment and highlights the vulnerability of fishes and other organisms through food webs.


Assuntos
Perciformes , Poluentes Químicos da Água/análise , Animais , Ecossistema , Monitoramento Ambiental , Peixes , Microplásticos , Plásticos
19.
Sci Total Environ ; 737: 140226, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32575024

RESUMO

Bioaccumulation of pharmaceuticals in fish exposed to contaminated water can be shaped by their capability to metabolize these xenobiotics, affecting their toxicity and animal welfare. In this study the in vivo metabolization of the antidepressant venlafaxine by the juvenile marine fish meagre (Argyrosomus regius) was evaluated using a combined target and suspect screening analytical approach. Thirteen venlafaxine metabolites were identified, namely N-desmethylvenlafaxine and N,N-didesmethylvenlafaxine, which were unequivocally identified using analytical standards, and 11 more tentatively identified by suspect screening analysis, including two Phase II metabolites formed by amino acid conjugation. All of them were detected in the liver, while in plasma and brain only 9 and 6 metabolites, respectively, were detected. Based on these findings, for the first time, a tentative metabolization pathway of venlafaxine by A. regius is proposed. Contrarily to what happen in humans, N-demethylation was identified as the main route of metabolization of venlafaxine by fish. Our findings highlight species-specificity in the metabolization of venlafaxine and allow a better understanding of venlafaxine's toxicokinetic in fish. These results emphasize the need to investigate the biotransformation of xenobiotics by non-target organisms to have an integrated overview of their environmental exposure and to improve future evaluations of environmental risk assessment.


Assuntos
Perciformes , Animais , Antidepressivos , Peixes , Cloridrato de Venlafaxina
20.
Sci Total Environ ; 735: 139462, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32474249

RESUMO

Environmental DNA (eDNA) can exist in water with various sizes and states. Among them, relative to extra-cellular DNA, intra-cellular DNA such as cell and tissue fragments can mainly be detected at larger size fractions, and may be protected from enzymatic DNA degradation processes. Here, we verified the hypothesis that the selective collection of such large-sized eDNA enhances the efficiency of capturing less-degraded eDNA, based on a tank experiment using Japanese Jack Mackerel (Trachurus japonicus) as a model species. We concentrated different volumes of rearing water using the filters with different pore sizes (0.7 µm and 2.7 µm), and quantified the copy number of short and long mitochondrial and short nuclear DNA fragments of target species in water samples. As a result, the ratio of long to short eDNA concentrations was higher in the larger pore size filter, which would support our stated hypothesis. In addition, the ratio of nuclear to mitochondrial eDNA was lower in the larger pore size filter. These results imply a difference in the persistence of nuclear and mitochondrial DNA between intra- and extra-cellular environments. Moreover, larger filter pore size did not necessarily decrease the yields of eDNA, and there was little difference in yields in smaller filtration volumes. The findings of this study indicate the potential to select information from eDNA signals by focusing on eDNA of specific size and state, which may contribute to efficient utilization of the information on species taxonomy and physiology in water samples.


Assuntos
DNA Ambiental , Perciformes , Animais , DNA Mitocondrial , Filtração , Peixes
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