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1.
Zootaxa ; 4772(3): zootaxa.4772.3.6, 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-33055605

RESUMO

A new barracuda, Sphyraena stellata, is described on the basis of 41 specimens [98.0-587.0 mm standard length (SL)] collected from the Indo-Pacific. The new species can be distinguished from all congeners in having the following combination of characters: one gill raker on first gill arch; pelvic-fin insertion located slightly before vertical through first dorsal-fin origin; pored lateral-line scales 134-141 (modally 137), total lateral-line scales 139-148 (146); scales above and below lateral line 15-17 (15) and 14-16 (15), respectively; snout comparatively short, its length 13.6-15.8 (mean 14.4) % SL; upper jaw short, its posterior tip not reaching to below anterior nostril, its length 10.0-12.2 (10.8) % SL; eye small, orbit diameter and depth 4.3-7.0 (4.9) and 3.9-5.6 (4.5) % SL, respectively; anal-fin base shortish, its length 6.9-8.1 (7.5) % SL; last dorsal- and anal-fin ray lengths 4.0-5.6 (4.7) and 3.6-5.6 (4.6) % SL, respectively; anus not close to anal-fin origin, anterior and posterior margins of former to anal-fin origin 7.5-11.9 (9.9) and 5.2-8.3 (6.8) % of head length, respectively; head sensory canal pores on suborbital area simple or slightly branched, their lowermost parts not close to margin of lacrimal bone, large smooth area lacking canal pores on mid-margin of lacrimal bone; two yellow stripes on lateral surface of body (remaining as black stripes in preserved specimens); and caudal fin gray. In addition, S. helleri Jenkins, 1901 and S. novaehollandiae Günther, 1860, both being closely related to the new species, are redescribed on the basis of 4 (243.3-545.8 mm SL) and 15 (270.8-598.0 mm SL) specimens, including holotypes, respectively, with new diagnostic characters proposed for both species.


Assuntos
Perciformes , Animais , Cor , Brânquias , Cabeça
2.
Zootaxa ; 4834(1): zootaxa.4834.1.5, 2020 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-33056133

RESUMO

A new species of toby fish, Canthigaster aziz, is described based on a single specimen collected from the northern Red Sea off Saudi Arabia. The holotype was trawled from a depth of 315 m, the second deepest record for the genus. The new species is distinguished from other species of the genus by the following combination of characters: 8 dorsal-fin rays; 8 anal-fin rays; 15 pectoral-fin rays; dorsal-fin origin opposite to anal-fin origin; five diffuse, saddle-like, black blotches along dark yellowish dorsal edge of body between nape and dorsal-fin origin; dorsal half of body light brown with concentrated dark pigments just behind eye and with a longitudinal, irregular, pale golden stripe running from area just behind eye to dorsal side of caudal peduncle; ventral half of posterior part of body pinkish with tiny subcutaneous black spots; head and ventral half of body before anus white; and all fins uniformly pale grey. A phylogenetic analysis of the mitochondrial COI barcoding region resulted in a new and unique evolutionary lineage for the new species that is sister to a clade composed of C. leoparda, C. pygmaea and C. valentini. It also shows C. aziz to be evolutionary deeply divergent from its closest congeners. In addition to the description of the new species, comparisons with congeners and a revised key to the Indo-Pacific species are provided.


Assuntos
Perciformes , Tetraodontiformes , Distribuição Animal , Animais , Oceano Índico , Filogenia
3.
Zootaxa ; 4834(1): zootaxa.4834.1.8, 2020 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-33056136

RESUMO

Corcyrogobius pulcher sp. nov. is described from off Île de Ngor, Dakar, Senegal. Corcyrogobius pulcher is distinguished from its two congeners by having the rear edge of the jaws ending posteriorly below mideye, second dorsal fin I/9, pectoral fin rays 17, pelvic fins oval or truncated posteriorly, scales in lateral series 26-27, anterior oculoscapular head canal with pore ß, suborbital row b of sensory papillae anteriorly beginning below vertical of posterior edge of eye, dark vertical caudal bar, branchiostegal membrane without intense dark spot, cheek with two oblique whitish stripes, the first going from the eye downwards and forward to the posterior jaws, the second on the preopercular, alternating with brown oblique stripe going from behind the eye downwards and forward across the cheek. Furthermore, mitochondrial COI-barcoding data unambiguously support the species-level distinctiveness of the three Corcyrogobius species. A key to the species of Corcyrogobius is provided.


Assuntos
Perciformes , Animais , Peixes , Cabeça , Senegal
4.
Zootaxa ; 4852(5): zootaxa.4852.5.2, 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-33056394

RESUMO

A taxonomic review of the Scorpaena papillosa species complex, defined here as having 10 dorsal-fin soft rays, coronal spines, and two upwardly directed spines on the lacrimal bone, resulted in the recognition of two species and two subspecies, Scorpaena papillosa (Schneider Forster, 1801) including two subspecies, i.e., S. papillosa papillosa (New Zealand) and S. papillosa ergastulorum Richardson, 1842a (southeastern Australia), and S. vesperalis n. sp. (southwestern Australia). Scorpaena p. papillosa and S. p. ergastulorum, are redescribed, with designation of a neotype for S. p. papillosa. Scorpaena vesperalis n. sp., described from coastal waters off southwestern Western Australia on the basis of 57 specimens, is characterized as follows: pectoral-fin rays 14-16; longitudinal scale rows 37-41; body depth 32.3-39.5 % of SL; upper-jaw length 19.6-22.5 % of SL; maxilla depth 5.7-7.3 % of SL; postorbital length 18.2-21.3 % of SL; least distance between interorbital ridges 1.4-2.7 % of SL; 1st anal-fin spine length 7.2-10.0 % of SL; anterior lacrimal spine simple, without additional small spinous points on its posterior margin; a single united pore behind the lower jaw symphysial knob; relatively large supraocular tentacle; all fins of preserved specimens usually uniformly whitish to translucent; and small body size (maximum recorded length 67.6 mm SL). The new species is likely endemic to southwestern Australia. Morphological ontogenetic changes in the relative lengths of some body proportions in the three taxa are also discussed.


Assuntos
Perciformes , Animais , Austrália , Peixes
5.
Zootaxa ; 4852(1): zootaxa.4852.1.8, 2020 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-33056713

RESUMO

The checklist by Robertson et al. (2017) of fishes from the tropical eastern Pacific included information on three members of the family Triglidae: Bellator loxias (Jordan, 1897), Prionotus ruscarius and P. stephanophrys Lockington, 1881. Unfortunately, the identification of four specimens as P. ruscarius is incorrect, as they are Bellator gymnostethus. We thank Benjamin Victor for bringing these misidentifications to our notice through his work with mtDNA sequence data from the Barcode of Life Database (BOLD: http://www.boldsystems.org). The photographs of the four specimens on the BOLD website clearly depict a Bellator species rather than a Prionotus. However, the photograph in the 2017 paper (Figure 75, page 78), is correctly identified and labelled as P. ruscarius, and this species was collected on the cruise of the Miguel Oliver discussed in Robertson et al. (2017), see Benavides Moreno et al. (2019). This correction brings the number of triglids collected on that cruise to four species.


Assuntos
Perciformes , Animais , DNA Mitocondrial , Peixes
6.
Zootaxa ; 4762(1): zootaxa.4762.1.1, 2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33056890

RESUMO

Eelpout species of the genus Lycenchelys Gill, 1884 recorded from Japanese waters are taxonomically revised. This study recognizes the following 11 species from Japanese waters as valid: Lycenchelys albomaculata Toyoshima, 1983, Lycenchelys aurantiaca Shinohara Matsuura, 1998, Lycenchelys hippopotamus Schmidt, 1950, Lycenchelys maculata Toyoshima, 1985, Lycenchelys makushok Fedorov Andriashev, 1993, Lycenchelys melanostomias Toyoshima, 1983, Lycenchelys rassi Andriashev, 1955, Lycenchelys remissaria Fedorov, 1995, Lycenchelys ryukyuensis Shinohara Anderson, 2007, Lycenchelys squamosa Toyoshima, 1983 and Lycenchelys tohokuensis Anderson Imamura, 2002. We redescribe species in detail based on type specimens as well as additional specimens in many cases. The synonymy of Lycenchelys brevimaxillaris Toyoshima, 1985 with L. melanostomias is supported in this study. Sexual dimorphism and changes with growth are revealed in L. albomaculata, L. aurantiaca, L. hippopotamus, L. makushok, L. melanostomias and L. rassi, all based on 10 or more specimens, for relative head length, head width, and upper and lower jaw lengths. In addition, we also found that the sizes at which sexual dimorphism can be recognized, and the tendencies for change with growth, differ among species. Furthermore, the dimorphism in head length is influenced by the snout length, eye diameter and/or postorbital length in L. albomaculata and L. aurantiaca.


Assuntos
Perciformes , Animais , Peixes , Japão , Mandíbula , Caracteres Sexuais
7.
PLoS One ; 15(8): e0230985, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32845879

RESUMO

Spearfishing is currently the primary approach for removing invasive lionfish (Pterois volitans/miles) to mitigate their impacts on western Atlantic marine ecosystems, but a substantial portion of lionfish spawning biomass is beyond the depth limits of SCUBA divers. Innovative technologies may offer a means to target deepwater populations and allow for the development of a lionfish trap fishery, but the removal efficiency and potential environmental impacts of lionfish traps have not been evaluated. We tested a collapsible, non-containment trap (the 'Gittings trap') near artificial reefs in the northern Gulf of Mexico. A total of 327 lionfish and 28 native fish (four were species protected with regulations) recruited (i.e., were observed within the trap footprint at the time of retrieval) to traps during 82 trap sets, catching 144 lionfish and 29 native fish (one more than recruited, indicating detection error). Lionfish recruitment was highest for single (versus paired) traps deployed <15 m from reefs with a 1-day soak time, for which mean lionfish and native fish recruitment per trap were approximately 5 and 0.1, respectively. Lionfish from traps were an average of 19 mm or 62 grams larger than those caught spearfishing. Community impacts from Gittings traps appeared minimal given that recruitment rates were >10X higher for lionfish than native fishes and that traps did not move on the bottom during two major storm events, although further testing will be necessary to test trap movement with surface floats. Additional research should also focus on design and operational modifications to improve Gittings trap deployment success (68% successfully opened on the seabed) and reduce lionfish escapement (56% escaped from traps upon retrieval). While removal efficiency for lionfish demonstrated by traps (12-24%) was far below that of spearfishing, Gittings traps appear suitable for future development and testing on deepwater natural reefs, which constitute >90% of the region's reef habitat.


Assuntos
Conservação dos Recursos Naturais/métodos , Recuperação e Remediação Ambiental/métodos , Espécies Introduzidas/tendências , Animais , Biomassa , Recifes de Corais , Ecossistema , Peixes/crescimento & desenvolvimento , Golfo do México , Perciformes/crescimento & desenvolvimento , Densidade Demográfica , Dinâmica Populacional , Comportamento Predatório
8.
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
9.
PLoS One ; 15(8): e0238167, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32857792

RESUMO

The ciliated protozoan Cryptocaryon irritans infects a wide range of marine fish and causes the highly lethal white spot disease. This parasite possesses three morphologically and physiologically distinct life stages: an infectious theront, a parasitic trophont, and an asexually reproductive tomont. In the past few years, several attempts have been made to help elucidate how C. irritans transforms from one stage to another using transcriptomic or proteomic approaches. However, there has been no research studying changes in transcription profiles between different time points of a single C. irritans life stage-the development of this parasite. Here we use RNA-seq and compare gene expression profiles of theront cells collected by 1 and 10 hrs after they emerged from tomonts. It has been shown that infectivity of theront cells declines 6-8 hours post-emergence, and we used this characteristic as a physiological marker to confirm the aging of theront cells. We identified a total of 41 upregulated and 90 downregulated genes that were differentially expressed between young and aging theront cells. Using Blast2Go to further analyze functions of these genes, we show that genes related to energy production are downregulated, but quite surprisingly many genes involved in transcription/translation processes are upregulated. We also show that expression of all nine detectable agglutination/immobilization antigen genes, with great sequence divergence, is invariably downregulated. Functions of other differentially expressed genes and indications are also discussed in our study.


Assuntos
Envelhecimento/metabolismo , Cilióforos/metabolismo , Cilióforos/patogenicidade , Animais , Cilióforos/genética , Cilióforos/crescimento & desenvolvimento , Infecções por Cilióforos/veterinária , Doenças dos Peixes/parasitologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Perciformes , Análise de Sequência de RNA , Transcriptoma
10.
PLoS One ; 15(8): e0237817, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32810160

RESUMO

Transitive inference (TI) is the ability to infer unknown relationships from previous information. To test TI in non-human animals, transitive responding has been examined in a TI task where non-adjacent pairs were presented after premise pair training. Some mammals, birds and paper wasps can pass TI tasks. Although previous studies showed that some fish are capable of TI in the social context, it remains unclear whether fish can pass TI task. Here, we conducted a TI task in cleaner wrasses (Labroides dimidiatus), which interact with various client fishes and conspecifics. Because they make decisions based on previous direct and indirect interactions in the context of cleaning interactions, we predicted that the ability of TI is beneficial for cleaner fish. Four tested fish were trained with four pairs of visual stimuli in a 5-term series: A-B+, B-C+, C-D+, and D-E+ (plus and minus denote rewards and non-rewards, respectively). After training, a novel pair, BD (BD test), was presented wherein the fish chose D more frequently than B. In contrast, reinforcement history did not predict the choice D. Our results suggest that cleaner fish passed the TI task, similar to mammals and birds. Although the mechanism underlying transitive responding in cleaner fish remains unclear, this work contributes to understanding cognitive abilities in fish.


Assuntos
Aprendizagem , Perciformes/fisiologia , Animais , Comportamento de Escolha , Feminino , Masculino , Recompensa
11.
PLoS One ; 15(8): e0237996, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32822408

RESUMO

Identifying juvenile habitats is critical for understanding a species' ecology and for focusing spatial fishery management by defining references like essential fish habitat (EFH). Here, we used vector autoregressive spatio-temporal models (VAST) to delineate spatial and temporal patterns in juvenile density for 13 commercially important species of groundfishes off the US west coast. In particular, we identified hotspots with high juvenile density. Three qualitative patterns of distribution and abundance emerged. First, Dover sole Microstomus pacificus, Pacific grenadier Coryphaenoides acrolepis, shortspine thornyhead Sebastolobus alascanus, and splitnose rockfish Sebastes diploproa had distinct, spatially-limited hotspots that were spatially consistent through time. Next, Pacific hake Merluccius productus and darkblotched rockfish Sebastes crameri had distinct, spatially limited hotspots, but the location of these hotspots varied through time. Finally, arrowtooth flounder Atheresthes stomias, English sole Parophrys vetulus, sablefish Anoplopoma fimbria, Pacific grenadier Coryphaenoides acrolepis, lingcod Ophiodon elongatus, longspine thornyhead Sebastolobus altivelis, petrale sole Eopsetta jordani, and Pacific sanddab Citharichthys sordidus had large hotspots that spanned a broad latitudinal range. These habitats represent potential, if not likely, nursery areas, the location of which will inform spatial management.


Assuntos
Ecossistema , Peixes/fisiologia , Animais , California , Peixes/crescimento & desenvolvimento , Linguado/fisiologia , Gadiformes/fisiologia , Perciformes/fisiologia
12.
PLoS One ; 15(8): e0237366, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32834000

RESUMO

The modern Gobioidei (Teleostei) comprise eight families, but the extinct †Pirskeniidae from the lower Oligocene of the Czech Republic indicate that further families may have existed in the past. However, the validity of the †Pirskeniidae has been questioned and its single genus †Pirskenius has been assigned to the extant family Eleotridae in previous works. The objective of this study is to clarify the status of the †Pirskeniidae. Whether or not the †Pirskeniidae should be synonymised with the Eleotridae is also interesting from a biogeographical point of view as Eleotridae is not present in Europe or the Mediterranean Sea today. We present new specimens and re-examine the material on which the two known species of †Pirskenius are based (†P. diatomaceus Obrhelová, 1961; †P. radoni Prikryl, 2014). To provide a context for phylogenetically informative characters related to the palatine and the branchiostegal rays, three early-branching gobioids (Rhyacichthys, Protogobius, Perccottus), an eleotrid (Eleotris) and a gobiid (Gobius) were subjected to micro-CT analysis. The new data justify revalidation of the family †Pirskeniidae, and a revised diagnosis is presented for both †Pirskenius and †Pirskeniidae. Moreover, we provide for the first time an attempt to relate a fossil gobioid to extant taxa based on phylogenetic analysis. The results indicate a sister-group relationship of †Pirskeniidae to the Thalasseleotrididae + Gobiidae + Oxudercidae clade. Considering the fossil record, the arrival of gobioids in freshwater habitats in the early Oligocene apparently had generated new lineages that finally were not successful and became extinct shortly after they had diverged. There is currently no evidence that the Eleotridae was present in the European ichthyofauna in the past.


Assuntos
Evolução Biológica , Perciformes , Filogenia , Animais , Geologia
13.
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
14.
Sci Total Environ ; 745: 140976, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-32736105

RESUMO

Osmotic stress is associated with heightened immune functions and altered microbiota in the fish intestine. In this study, we explored the effects of hypoosmotic stress on the intestine of euryhaline yellowfin seabream (Acanthopagrus latus) after acute exposure to brackish water, low-saline water, and freshwater environments. The results showed that hypoosmotic stress reshaped the composition of the microbial community and altered the gene expression in the intestine. Probiotics Lactobacillus and Pseudomonas showed higher relative abundance in a brackish water environment, whereas pathogenic bacteria, including Vibrio and Aeromonas, were more abundant in the freshwater environment. At the transcriptional level, osmoregulation-related genes were identified as up/down regulated differentially expressed genes (DEGs) as well as a series of immune-related DEGs associated with pathogen recognition, antimicrobial ability, pro-inflammatory cytokines, cell apoptosis, and antioxidant defense. Physiological analysis showed that Na+ K+-ATPase activity was significantly inhibited by hypoosmotic stress in freshwater. Meanwhile, the intestinal antioxidant defense system of yellowfin seabream was challenged. Correlation network analysis demonstrated the close interactions among intestinal microbes, differentially expressed genes, and physiological parameters. This study provides the critical insights into the function of the intestine fish encountering hypoosmotic stress.


Assuntos
Microbioma Gastrointestinal , Perciformes , Dourada , Vibrio , Animais , Antioxidantes
15.
Chemosphere ; 260: 127611, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32758780

RESUMO

Mercury (Hg) is known as a highly toxic heavy metal, and its toxicity varies depending on its form due to different toxicokinetics between inorganic and organic Hg. Limited information on comparison of Hg toxicity concerning its chemical form by oral exposure is currently available in cultured fishes. Therefore, we conducted a comparative study to have a better understanding of distinct toxic effects between mercuric chloride (HgCl2) and methylmercury chloride (CH3HgCl) in Korean rockfish. The 12-weeks dietary exposure of HgCl2 and CH3HgCl with its graded levels (0.4-6.4 ppm) (2 × 5 factorial design) in the young-of-the-year rockfish (initial weight: 82 ± 0.3 g) resulted in neither interactive nor main effects on whole-organism responses, including growth, feed utilization, and survival. However, the distinct pattern of Hg accumulation between the two forms in dorsal muscle, brain, liver and kidney tissues was observed, showing that the rockfish fed the CH3HgCl-contained diets exhibited the dose-dependent accumulation throughout the sampling points (1, 2, 4, 8, and 12 weeks post feeding), whereas those fed the HgCl2-contained diets did not show such response. The CH3HgCl exposure induced higher oxidative stress and immunotoxicity, reflected by the elevated plasma superoxide dismutase and lysozyme activities, respectively. In addition, the CH3HgCl-induced alteration in plasma measurements, including the plasma aspartate transaminase activity and total protein level was found. Taken together, the dietary exposure of methylmercury chloride had more pronounced toxic effects than mercuric chloride in the young-of-year rockfish, needed to be taken into consideration for regulation of maximum allowed levels for Hg by its chemical form.


Assuntos
Cloreto de Mercúrio/toxicidade , Compostos de Metilmercúrio/toxicidade , Perciformes/fisiologia , Poluentes Químicos da Água/toxicidade , Animais , Encéfalo/metabolismo , Dieta , Mercúrio/metabolismo , Estresse Oxidativo , Perciformes/metabolismo , República da Coreia , Superóxido Dismutase/metabolismo
16.
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
17.
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
18.
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
19.
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
20.
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
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