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1.
Sci Total Environ ; 756: 144052, 2021 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-33310223

RESUMO

Dam operations considerably influence water temperature regimes in rivers, which affects fish spawning activities. Previous studies have focused on the effects of critical temperature (CT) alterations during the spawning period, and largely ignored the effects of accumulated temperature (AT) alterations on gonadal development. Successful spawning relies on the simultaneous achievement of the two thermal requirements at appropriate times. River damming may cause a mismatch between the times of achieving CT and AT thresholds, and in turn influence fish reproduction. In the present study, spawning events of Coreius heterodon (C. heterodon) from 2009 to 2015 in the upper reaches of the Yangtze River, which are under the influence of cascade dams, were analysed based on the times of achievement of CT and AT thresholds. The CT and AT thresholds for C. heterodon spawning were 18.4 °C and 1324.9 °C·d, respectively. Under pre-impoundment conditions, the time of achievement of the AT threshold was 23 d on average later than that under post-impoundment conditions; however, the time of achievement of the CT threshold was similar under both conditions. The time of achievement of the AT threshold was 10 d earlier than that of achievement of the CT threshold in post-impoundment conditions. Earlier achievement of AT thresholds was followed by reduced spawning. The alteration of temperature rhythm caused by reservoir operations could be the major factor decreasing spawning abundance after river damming. The results of the present study could facilitate sustainable reservoir operations with regards to water temperature management, and thereby improve the conservation of fish resources.


Assuntos
Cyprinidae , Rios , Animais , Monitoramento Ambiental , Reprodução , Temperatura
2.
Sci Total Environ ; 751: 141634, 2021 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-32882550

RESUMO

Current research is increasingly focusing on the ecotoxicity of anthropogenic micro-pollutants and their degradation and transformation products resulting from biological and chemical treatment processes. These products enter the aquatic environment through various routes and may endanger aquatic organisms and plants. In this study, five neonicotinoids from the EU watchlist and their degradation products induced by UVC irradiation were examined. All identified photoinduced degradation or transformation products were subsequently submitted to Quantitative Structure Activity (QSAR) analysis. Among the investigated structures, 15 substances already identified in previous studies and eleven new transformation products were analyzed. By using QSAR analysis, it became possible to predict ecotoxicity of individual substances with mere computational effort. Starting from the chemical structure, lower toxicity against green algae and invertebrates was predicted for the transformation products in general. For other aquatic target organisms, such as branchiopoda, actinopterygii and fathead minnow, the residual hazardous effect as compared to the initial compound depends on the presence of specific structural elements. For the neonicotinoids investigated, the cleavage or elimination of the nitrile or nitro group through the degradation process, was predicted to increase toxicity.


Assuntos
Clorófitas , Cyprinidae , Poluentes Químicos da Água , Animais , Ecotoxicologia , Neonicotinoides , Relação Quantitativa Estrutura-Atividade , Poluentes Químicos da Água/toxicidade
3.
Sci Total Environ ; 752: 141542, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32889256

RESUMO

The occurrence of microplastics (MPs) in the digestive tract of commercial Kutum fish, Rutilus frisii kutum was investigated. Fish samples, ranging from 33 to 48.5 cm fork length which sold for human consumption, were collected from local fish markets in Bandar-e Torkaman (the south-eastern of Caspian Sea) on November 2017, and March 2018. The MPs were characterized using optical microscopy, NR staining, and SEM-EDS for number, shape, color, surface morphology, and elemental composition. On average, 11.4 MP items per fish (0.015 items per 1 g fish wet weight) were found in Kutum's stomach at an individual detection rate of 80%. Around 66% of all identified MP items were < 500 µm, and 53% possessed light colors. Morphological researches indicated that fish ingested the degradation fragments from larger plastic pieces, fibers, and manufactured microbeads. Microfibers are the most dominant items accounting for over 75% of all MPs. The SEM images indicated the various degrees of erosions upon environmental exposure. Some MPs had surface cracks, broken margins, scaly appearances, and obvious pores. Considering the commercial importance which the Kutum plays for Iran's fishery, the potential effect of MPs on the trophic food web, particularly for human consumption and health, should be urgently investigated.


Assuntos
Cyprinidae , Poluentes Químicos da Água , Animais , Mar Cáspio , Monitoramento Ambiental , Humanos , Irã (Geográfico) , Microplásticos , Plásticos , Poluentes Químicos da Água/análise
4.
Sci Total Environ ; 752: 141938, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32898804

RESUMO

Secondary salinization of freshwater ecosystems is of increasing global concern. One of the main causes are the effluents of the potash mining industry containing high concentrations of major ions (Cl-, Na+, Mg2+, K+). In Germany, the ongoing discharge of effluents into the River Werra led to a strong impoverishment of the biodiversity and abundance of local species. Young cohorts of many freshwater fish are completely absent suggesting reproductive failure under these conditions. Therefore, the aim of the study was to experimentally investigate the effects of high concentrations and imbalances of ions that are prevalent in potash mining effluents on reproductive traits of native freshwater teleosts. Sperm motility parameters of the common roach, Rutilus rutilus, and European perch, Perca fluviatilis, were assessed as well as fertilization rate, egg size, hatching, malformations and mortality of embryonic and larval stages of roach. Concentrations of the permitted thresholds (HT) and future thresholds (LT) as well as three ion solutions containing high Mg2+ (Mg), high K+ (K) and both in combination (Mg + K) were tested. Curvilinear velocity and linearity of perch spermatozoa were elevated with potentially adverse effects on fertilization success. Sperm motility parameters and fertilization rate of roach were not affected. However, egg sizes of roach were increased in all groups due to the osmotic action of ions and in LT, premature hatch was observed. Furthermore, all groups comprised a higher number of malformations including pericardial edema and spine curvatures and group HT exhibited a higher mortality rate compared to control. The results clearly demonstrated that particularly the sum of high concentrations of ions, as prevalent in HT and LT, rather than individual ion species exerts detrimental effects on early development of roach potentially increasing overall mortality under natural conditions. These results emphasize that currently permitted and future thresholds are exceeding tolerated ion concentrations.


Assuntos
Cyprinidae , Percas , Animais , Misturas Complexas , Ecossistema , Alemanha , Humanos , Íons , Masculino , Mineração , Motilidade Espermática
5.
Chemosphere ; 263: 127911, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33297010

RESUMO

Antilipidemic drugs are routinely detected in effluent and surface waters downstream of wastewater treatment plants. A mixture exposure study with nine environmentally relevant antilipidemic drugs was performed with zebrafish (Danio rerio, ZF) and fathead minnow (Pimephales promelas, FHM) embryos to investigate the effects on sensitive embryologic stages. Zebrafish embryos were exposed nominally to: (a) 0.005 µM, (b) 0.05 µM, or (c) 0.5 µM of each drug in the mixture. Fathead minnow embryos were exposed nominally to: (a) 0.0005 µM, (b) 0.005 µM, or (c) 0.05 µM of each drug in the mixture. Several of the individual drug concentrations were within ranges previously found in the environment. Multiple metrics demonstrate that (a) exposure of ZF and FHM embryos to antilipidemic drugs during embryonic development results in lethal and sublethal effects, (b) ZF were more sensitive than FHM based on median lethal concentration (LC50 0.02 µM and 0.05 µM, respectively), but FHM exhibited more severe abnormal sublethal morphologies than zebrafish embryos, and (c) the sublethal effects differed between the two species. This model identified novel specific endpoints for assessing sensitive, sublethal effects of pharmaceuticals in the environment. Abnormal myofiber birefringence pattern, hemorrhage, and heart rate are not included in standard evaluations but each of these metrics demonstrated a dose-dependent response in this study. Results demonstrate risk to fish development with potential repercussions at the population level, especially if environmental concentrations increase.


Assuntos
Cyprinidae , Inibidores de Hidroximetilglutaril-CoA Redutases , Preparações Farmacêuticas , Poluentes Químicos da Água , Animais , Desenvolvimento Embrionário , Ácidos Fíbricos , Morbidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra
6.
Environ Pollut ; 270: 116245, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33359871

RESUMO

To assess genetoxicity and the underlying mechanisms of carbamazepine (CBZ) toxicity in fish, adult Chinese rare minnows (Gobiocypris rarus) were exposed to 1, 10, and 100 µg/L CBZ for 28 d. Comet assays indicated that hepatic DNA damage was significantly increased in groups of minnows exposed to CBZ at all concentrations in a dose-dependent manner compared to those of the control groups (p < 0.05). Liver levels of 8-hydroxydeoxyguanosine (8-OHdG) were significantly increased at 10 and 100 µg/L CBZ (p < 0.05). TUNEL assays indicated that the average apoptotic rates of the livers of female and male minnows were significantly increased following exposure to CBZ at all concentrations for 28 d (p < 0.05). Significant increases in caspase 3 and 9 activities after CBZ exposure at all concentrations and caspase 8 at 10 and 100 µg/L CBZ exposure reflected the presence of mitochondrial apoptosis (p < 0.05). The mRNA levels of gadd45a, mdm2, casp3 and casp9 in female and male minnows exposed to CBZ at all concentrations were significantly increased compared with those in the control groups (p < 0.05). Significant increases in the levels of p21 in female minnows exposed to 1 and 100 µg/L CBZ, p53 in female minnows at all CBZ treatments and bcl2 in male minnows exposed to 1 and 100 µg/L CBZ were observed, indicating p53 pathway activation. The inhibition of ras levels in females and males exposed to CBZ at all concentrations and increased levels of raf1 in males exposed to CBZ at all concentrations indicated Ras/Raf1/MAPK (ERK) activation. Therefore, the present study demonstrates that CBZ at environmentally relevant levels induces DNA damage and apoptosis in Chinese rare minnows by the Ras/Raf/ERK/p53 signaling pathway.


Assuntos
Cyprinidae , Poluentes Químicos da Água , Animais , Apoptose , Grupo com Ancestrais do Continente Asiático , Carbamazepina/toxicidade , Dano ao DNA , Feminino , Humanos , Fígado , Masculino , Transdução de Sinais , Proteína Supressora de Tumor p53/genética , Poluentes Químicos da Água/toxicidade
7.
Sci Total Environ ; 754: 142142, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33254860

RESUMO

Fish swimming behavior is a critical parameter for the design of vertical slot fishways. Although Schizothorax prenanti is a significant reproductive potamodromous migratory fish species in the upper reaches of the rivers in Southwest China, its swimming behavior has not been extensively researched. Therefore, in this study, a comparative experiment was conducted in vertical slot fishways to analyze the behavior of Schizothorax prenanti in response to different flow patterns, with respect to different slot positions. The experimental model was designed with a length scale of 1:4, and a method for selecting the appropriate fish size in the scaled physical model was proposed. Based on these experiments, it was found that the typical upstream trajectories of Schizothorax prenanti are traceable to the sidewall of the pool, which are characterized by low velocity and turbulent kinetic energy (TKE). The hydraulic variables exhibited an asymmetric distribution within the vertical slot, and the fish were found to pass through the area with the lowest velocity and TKE. A flow pattern with a guide wall length-to-pool width ratio of P/B = 0.25, in which Schizothorax prenanti can immediately find the sidewall, is suitable for fish migration. Therefore, this is the recommended value for the construction of effective vertical-slot fishway structures.


Assuntos
Cyprinidae , Natação , Animais , China , Reprodução , Rios
8.
Food Chem ; 334: 127498, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32688179

RESUMO

In this work, ultrasound-assisted enzymatic extraction (UAEE) conditions of umami compounds from Labeo rohita head (LRH) was optimised using the combination of fractional factorial design (FFD) and central composite design (CCD). Six factors that can potentially influence the degree of hydrolysis (DH), equivalent umami concentration (EUC), and extraction yield (EY) of umami extract were screened through FFD. The three most significant variables were further optimised using the CCD. The developed models were successfully fitted to the experimental data and used to determine optimal extraction conditions. The optimum DH (22.73%), EUC (6.61 g MSG/100 g protein), and EY (76.34%) of umami extract were achieved with a liquid-solid ratio of 3 (v/w), ultrasonication time of 19.20 min and hydrolysis time of 140.45 min. Besides, UAEE umami extract exhibited higher DH, EUC, EY, and umami taste compared to that of the conventional enzymatic extraction (CEE).


Assuntos
Produtos Pesqueiros/análise , Sonicação , Aminoácidos/análise , Animais , Cromatografia Líquida de Alta Pressão , Cyprinidae , Proteínas de Peixes/metabolismo , Hidrólise , Projetos de Pesquisa
9.
Chemosphere ; 263: 127927, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32814137

RESUMO

Prymnesium parvum continues to spread globally, producing harmful algal blooms that release toxins known to cause fish kills. While previous work has identified possible P. parvum toxin(s) (e.g., prymnesins, fatty acids, fatty acid amides) and investigated treatment strategies targeted at minimizing cell abundance, studies examining efficacy of treatment approaches to remove toxins are lacking. To understand influences of sunlight on toxins stability and toxicity to fish, acutely toxic P. parvum cultures were exposed to three light scenarios (lab dark control, field dark, and field light) and then evaluated for acute toxicity to fish and prymnesins abundance. Previous work showed acute toxicity to fathead minnow larvae was ameliorated after 2 h of sunlight exposure, and results observed herein found an identical trend. Acute toxicity disappeared in light exposed filtrate, but filtrate exposed to 35 °C without sunlight remained acutely toxic to fish. Additionally, six prymnesins were identified through high-resolution mass spectrometry and abundance corresponded to acute toxicity levels. Prymnesins were present at the highest level in filtrate that was acutely toxic but diminished in filtrate that was exposed to light and correspondingly ameliorated acute toxicity to fish. These findings suggest prymnesins are responsible for measured acute toxicity and are photo-labile, which represents an important implication for treatment strategies.


Assuntos
Haptófitas/crescimento & desenvolvimento , Lipoproteínas/química , Luz Solar , Toxinas Biológicas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Cyprinidae , Ácidos Graxos , Proliferação Nociva de Algas , Larva , Espectrometria de Massas
10.
Ecotoxicol Environ Saf ; 207: 111250, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32920311

RESUMO

Perfluoroalkyl substances (PFAS), including perfluorooctanoic acid (PFOA), are industrial chemicals that are of concern due to their environmental presence, persistence, bioaccumulative potential, toxicity, and capacity for long-range transport. Despite a large body of research on environmental exposure, insufficient chronic aquatic toxicity data exist to develop water quality targets for clean-up of federal contaminated sites in Canada. Thus, our objective was to assess the aqueous toxicity of PFOA in chronic tests with Hyalella azteca (amphipod) and early-life stage tests with Pimephales promelas (fathead minnow). Toxicity data were analyzed based on measured PFOA concentrations. Amphipod exposures were 42 d (0.84-97 mg/L) and examined survival, growth, and reproduction. Fathead minnow exposures were 21 d (0.010-76 mg/L), which encompassed hatching (5 d) and larval stages until 16 d post-hatch; endpoints included hatching success, deformities at hatch, and larval survival and growth. Amphipod survival was significantly reduced at 97 mg/L (42-d LC50 = 51 mg/L), but growth and reproduction were more sensitive endpoints (42-d EC50 for both endpoints = 2.3 mg/L). Fathead minnows were less sensitive than amphipods, exhibiting no significant effects in all endpoints with the exception of uninflated swim bladder, which was significantly higher at 76 mg/L (15%) than controls (0%). Maximum concentrations of PFOA are generally in the ng/L range in global surface waters, but can reach the µg/L range in close proximity to major source inputs; therefore, environmental concentrations are well below those that caused toxicity in the current study. Our data will provide valuable information with which to assess the risk of PFOA at contaminated sites, and to set a target for site remediation.


Assuntos
Anfípodes , Caprilatos/análise , Fluorcarbonetos/análise , Poluentes Químicos da Água/análise , Animais , Canadá , Cyprinidae/crescimento & desenvolvimento , Larva/efeitos dos fármacos , Reprodução/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Qualidade da Água
11.
Zootaxa ; 4894(2): zootaxa.4894.2.5, 2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33311084

RESUMO

Rasbora neilgherriensis Day, long considered a synonym of Rasbora daniconius or Rasbora dandia, is re-described and shown to be a valid species based on an examination of type and recently-acquired topotypical specimens from the Western Ghats of India. The species is characterised by a complete lateral line with 32-34 pored scales on body, ½5-6/1/2½ scales in transverse line on body, a mid-lateral stripe that is 2½ scales wide anterior to the pelvic fin and 1-1½ scales wide on the caudal peduncle, and a caudal fin that is emarginate to forked with broadly rounded lobes. The species was recorded from the Cauvery River Basin in Kerala and Tamil Nadu, India, at elevations ranging from 710 m to 2015 m above sea level, in stream stretches with relatively denser riparian canopy cover.


Assuntos
Cyprinidae , Animais , Rios
12.
Zootaxa ; 4894(1): zootaxa.4894.1.7, 2020 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-33311096

RESUMO

Alburnus nasreddini described from Lake Eber in Central Anatolia is a junior synonym of A. escherichii, a widespread species in adjacent Sakarya River drainage. We found no morphological characters to distinguish Alburnus nasreddini from A. escherichii and both are poorly distinguished on a molecular level also.


Assuntos
Cyprinidae , Animais , Lagos , Rios
13.
Dis Aquat Organ ; 142: 75-82, 2020 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-33210614

RESUMO

A new myxobolid species, Myxobolus zaikae n. sp., was found in the connective tissue near the kidney and liver blood vessels of the common roach Rutilus rutilus, while fish myxosporean fauna were being investigated in Lake Baikal, Russia. The parasites were studied on the basis of spore morphology as well as with histological and molecular methods. Mature spores of M. zaikae n. sp. are round or ellipsoidal in the frontal view and lemon-shaped in the lateral view, measuring 11.37 ± 0.11 µm (10.2-14.0 µm) in length, 10.29 ± 0.10 µm (9.6-11.0 µm) in width, and 6.3 ± 0.08 µm (5.8-7.1 µm) in thickness (mean ± SD; n = 50). Polar capsules are equal and pyriform, measuring 4.5 ± 0.07 µm (3.4-5.2 µm) in length and 2.9 ± 0.03 µm (2.6-3.3 µm) in width. Polar capsules contained polar filaments coiled with 5 to 6 turns. Phylogenetic analysis showed that this newly described species clusters with other myxobolid species infecting the connective tissue of different organs from Palearctic cyprinid fish.


Assuntos
Cyprinidae , Doenças dos Peixes , Myxobolus , Parasitos , Doenças Parasitárias em Animais , Animais , Brânquias , Lagos , Myxobolus/genética , Doenças Parasitárias em Animais/epidemiologia , Filogenia
14.
Bull Environ Contam Toxicol ; 105(5): 699-704, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33006036

RESUMO

Transportation of crude oil across North America's boreal ecozone creates the potential for spills in freshwater where less is known about the sensitivity of resident fish than for marine systems. The sensitivity of wild fathead minnows (FHM) to residual concentrations (ppb range) of the water accommodated fraction (WAF) of diluted bitumen (dilbit) was assessed by exposing them for 21 days followed by a 14 days depuration. Target concentrations were well below detection limits for GC-MS, but were estimated by dilution factor (1:100,000 and 1:1,000,000 WAF:water) to contain less than 0.0003 µg/L of polycyclic aromatic compounds. Confinement and handling stress caused by transfer of wild fish into tanks much smaller than their natural range resulted in mortality and lower body condition among all groups, but interactive effects of oil exposures still resulted in females with smaller cortical alveolar oocytes, and males with larger testicular lobe lumen sizes. Additional studies examining the compounded effects of stress and environmentally relevant oil exposures in wild fishes are needed.


Assuntos
Cyprinidae/crescimento & desenvolvimento , Exposição Ambiental/análise , Hidrocarbonetos/análise , Poluição por Petróleo/análise , Petróleo/análise , Poluentes Químicos da Água/análise , Animais , Exposição Ambiental/efeitos adversos , Feminino , Água Doce/química , Hidrocarbonetos/toxicidade , Masculino , América do Norte , Óvulo/efeitos dos fármacos , Óvulo/patologia , Petróleo/toxicidade , Poluição por Petróleo/efeitos adversos , Testículo/efeitos dos fármacos , Testículo/patologia , Poluentes Químicos da Água/toxicidade
15.
Zootaxa ; 4819(1): zootaxa.4819.1.5, 2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-33055672

RESUMO

Vanmanenia intermedia, which has long been synonymized with V. pingchowensis since 1980, is here revalidated using morphological characters and molecular evidences, and redescribed on the basis of topotypic specimens. This species is distinguished from all other congeneric species by the following combination of characters: triangular-shaped rostral lobules without secondary rostral barbels; distal edge of dorsal-fin slightly concave; no longitudinal black stripe on the flank; a longer snout (length 52.6-64.5 % of HL); a more backwards-placed anus (the vent to anal distance 34.7-46.1% of the pelvic to anal distance); a slender caudal peduncle (depth 9.1-11.3 % of SL); a longer anal-fin base (length 7.5-9.5 % of SL); and a smaller gill opening with its upper extremity closer to the level of the lower margin of the orbit. The validity of V. intermedia is also confirmed by its significant cyt b gene sequence divergence with all sampled congeneric species and its monophyly recovered in the cyt b gene-based phylogenetic analysis.


Assuntos
Cyprinidae , Cipriniformes , Animais , China , Filogenia , Rios
16.
Zootaxa ; 4803(3): zootaxa.4803.3.9, 2020 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-33056011

RESUMO

Maharaja Barbs (Teleostei: Cyprinidae), endemic to the high-altitude streams of the northern Western Ghats are currently represented by a single species, Puntius sahyadriensis. Integrative taxonomic analysis of these fishes reveals them to form a distinct clade within the Cyprinidae, for which we propose the name Waikhomia gen. nov. Waikhomia differs from Puntius and other closely related genera by a combination of characters including: barbels absent; last unbranched dorsal-fin ray smooth, with highly segmented apex; total vertebrae 30 (17 abdominal and 13 caudal); post-epiphysial fontanelle absent, frontals elongated, parietals narrow; infraorbital 2-4 large, deep and wide, overlapping cheek and preopercle; opercle not overlapping the interopercle laterally; free uroneural 2 absent; lateral line complete, with 23-25 perforated scales; pelvic fins jet black with tip of fins white; and body coloration consisting of multiple (6-8) spots and blotches on side of body. We also describe a new species of Waikhomia from the west-flowing Kali river system in the northern part of the Western Ghats, India. The new species, Waikhomia hira is distinguished from W. sahyadriensis by a combination of characters including a distinct body coloration, consisting of 7-8 small, rhomboidal spots arranged across the lateral-line scale row; 23--25 perforated lateral line scales; 10 pre-dorsal scales and 2-3 sparsely spaced gill rakers on epibranchial 1. Further, W. hira differs from its sister taxon, W. sahyadriensis, by a raw genetic distance ranging from 4.3-4.9% in partial cytochrome oxidase subunit 1, and 7.0-8.2% in partial cytochrome b genes.


Assuntos
Cyprinidae , Nadadeiras de Animais , Animais , Citocromos b , Índia , Rios
17.
Zootaxa ; 4790(2): zootaxa.4790.2.8, 2020 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-33055845

RESUMO

Rhodeus flaviventris, a new species, is described from the Le-An River, a tributary flowing into Poyang Lake in the Yangtze River basin, in Jiangxi Province, China. It is distinguished from all congeners by the combination of characters: branched dorsal-fin rays 9 (9-10); branched anal-fin rays 9 (9-10); longest simple rays of dorsal and anal fins thick and stiff; longitudinal scale series 33-34; transverse scale series 11 (10-12); pored scales 4-7; vertebrae 32-34; spindle-shaped eggs with major axis of 3.1-3.7 mm; color pattern of nuptial males (iris yellowish, belly yellow, central part of caudal fin orange, dorsal and anal fins with reddish-orange stripe).


Assuntos
Cyprinidae , Animais , China , Cor , Masculino , Rios
18.
Aquat Toxicol ; 228: 105616, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33039795

RESUMO

Understanding internal dose metrics is integral to adequately assess effects environmental contaminants might have on aquatic wildlife, including fish. In silico toxicokinetic (TK) models are a leading approach for quantifying internal exposure metrics for fishes; however, they often do not adequately consider chemicals that are actively biotransformed and have not been validated against early-life stages (ELS) that are often considered the most sensitive to the exposure to contaminants. To address these uncertainties, TK models were parameterized for the rapidly biotransformed chemical benzo[a]pyrene (B[a]P) in embryo-larval and adult life stages of fathead minnows. Biotransformation of B[a]P was determined through measurements of in vitro clearance. Using in vitro-in vivo extrapolation, in vitro clearance was integrated into a multi-compartment TK model for adult fish and a one-compartment model for ELS. Model predictions were validated using measurements of B[a]P metabolites from in vivo flow-through exposures to graded concentrations of water-borne B[a]P. Significantly greater amounts of B[a]P metabolites were observed with exposure to greater concentrations of parent compound in both life stages. However, when assessing biotransformation capacity, no differences in phase I or phase II biotransformation were observed with greater exposures to B[a]P. Results of modelling suggested that biotransformation of B[a]P can be successfully implemented into in silico models to accurately predict life stage-specific abundances of B[a]P metabolites in either whole-body larvae or the bile of adult fish. Models developed increase the scope of applications in which TK models can be used to support environmental risk assessments.


Assuntos
Benzo(a)pireno/toxicidade , Cyprinidae/metabolismo , Larva/efeitos dos fármacos , Modelos Biológicos , Poluentes Químicos da Água/toxicidade , Animais , Benzo(a)pireno/metabolismo , Transporte Biológico , Simulação por Computador , Cyprinidae/crescimento & desenvolvimento , Larva/metabolismo , Desentoxicação Metabólica Fase I , Desintoxicação Metabólica Fase II , Toxicocinética , Poluentes Químicos da Água/metabolismo
19.
Zootaxa ; 4768(2): zootaxa.4768.2.3, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33056523

RESUMO

Sarcocheilichthys vittatus, a new species of gudgeon, is described from the Gan-Jiang and Fu-He flowing into the Poyang Lake Basin in Jiangxi Province, South China. It is similar to S. parvus and S. caobangensis in having a longitudinal black band extending from the snout tip to the caudal-fin base, a character separating them from all other congeneric species, but distinct from S. parvus in having more lateral-line scales, no longitudinal yellowish stripe above the lateral black band on the flank and no barbels, and from S. caobangensis in possessing two shorter lateral lobes of the lower lip restricted only to the side of the lower jaw, no black spots along the dorsal-fin base and a stouter caudal peduncle. Its validity was also warranted by a molecular phylogenetic analysis based on the cyt b gene. Critical notes were provided on some currently recognized Chinese congeners.


Assuntos
Cyprinidae , Animais , China , Lagos , Filogenia
20.
Zootaxa ; 4763(3): zootaxa.4763.3.6, 2020 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33056857

RESUMO

Alburnoides turani, new species, from the Filyos River drainage is described and the distribution of the nine other Alburnoides species known from the southern Black Sea basin is revised. Alburnoides turani is distinguished by having a naked ventral keel, or the keel is covered with 1-3 scales between the posterior pelvic-fin base and the anus, an interorbital distance wider than the eye diameter and the snout length, 48-55 total lateral-line scales, 5-6 scale rows between the anal-fin origin and the lateral line, 13½-14½ branched anal-fin rays, and 41-42 total vertebrae.


Assuntos
Cyprinidae , Animais , Mar Negro , Rios
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