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1.
Sci Total Environ ; 804: 150050, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34509851

RESUMO

Fish larvae play an important structuring role for their prey and show ontogenetic shifts in diet. Changes in diet differ between species and habitats and may also be affected by turbidity (eutrophication). We investigated the diet (stomach content) and the food selection (ratio of ingested prey and prey availability) of roach and perch larvae in a clear lake and of roach, perch and pikeperch larvae in a turbid lake multiple times during spring to autumn. The diet of the fish larvae changed with size, and for roach and perch larvae between the lakes. Coexisting species of fish larvae had different diets in the two lakes, pointing to resource partitioning; yet, in the clear lake, medium-sized larvae had a high diet overlap, suggesting a competitive relationship at this developmental stage. In the clear lake, roach larvae showed diel differentiation in diet, while perch demonstrated diet shifts between habitats, which probably aided in reducing competition and also evidenced an effect of light on the larval prey capture and/or predator-fish larvae interactions. In the turbid lake, roach and perch larvae did not reveal differences in diet between habitats or time of the day, owing to homogeneity of food items and poor light conditions. However, the diet of pikeperch larvae differed between day and night following daily variations in the abundance of its preferred prey. The roach larvae were highly selective for Bosmina, Daphnia and benthic cladocerans, perch larvae generally consumed what was available, while pikeperch primarily preyed on cyclopoid copepodites. We conclude that turbidity acted as a cover for fish larvae in the turbid lake. Under eutrophication-induced turbidity scenarios the effects of fish larvae on their prey are stronger (i.e., high selectivity for several resources) than that of larvae in clear waters, creating a negative feedback on the path to restore water clarity.


Assuntos
Lagos , Percas , Animais , Dieta , Preferências Alimentares , Larva , Água
2.
Sci Total Environ ; 802: 149800, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34525752

RESUMO

Aquaculture is one of the fastest growing food producing industries globally, providing ~50% of fish for human consumption. However, the rapid growth of aquaculture presents a range of challenges including balancing environmental impact that can be influenced by variations in climatic conditions. Monitoring of physicochemical parameters is traditionally used to evaluate aquaculture output quality; however, this approach does not indicate the cumulative ecotoxicological effects on receiving waters. Specifically, this case study investigated the relationship between measuring traditional physicochemical parameters and the health of the alga Pseudokirchneriella subcapitata in order to evaluate the potential ecotoxicological effects of freshwater aquaculture on the receiving aquatic ecosystem in the Irish midlands. This constituted the first 2-year longitudinal study conducted in 2018 and 2019 that reports on the efficacy of using algae as a natural bioindicator to monitor and assess freshwater aquaculture wastewater from a traditional flow-through fish farm producing Eurasian Perch (Perca fluviatilis); monitoring was compared over a same six-month period in the same location each year. Findings demonstrated significant differences between the two monitoring periods when using P. subcapitata for assessing the quality of aquaculture intake (P = 0.030) and output (P = 0.039). No stimulatory effects were observed during 2019 unlike >50% rates experienced the previous year. These observations coincided with changes in climatic conditions whereby the 2018 period experienced extended levels of drought; whereas non-drought conditions were observed during 2019. Findings suggest that reliance upon traditional monitoring techniques may not provide sufficient robustness or versatility to address emerging issues, such as extremes in climate variance, which may influence the future intensive sustainability of freshwater aquaculture. This research supports the complementary use of P. subcapitata as a rapid and simple early-warning bioindicator for measuring aquaculture output quality on receiving aquatic ecosystems.


Assuntos
Microalgas , Percas , Animais , Aquicultura , Ecossistema , Biomarcadores Ambientais , Humanos , Irlanda , Estudos Longitudinais , Águas Residuárias
3.
Sci Total Environ ; 802: 149620, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34461474

RESUMO

Triggered by the adoption of the Water Framework Directive, a variety of fish-based systems were developed throughout Europe to assess the ecological status of lakes. This paper provides a comprehensive overview of all existing systems and summarizes sampling methods, fish community traits (metrics) and the relevant anthropogenic pressures assessed by them. Twenty-one European countries developed fish-based assessment systems. Three countries each developed two distinct systems to approach different ecoregions, either to use different data, or to assess different lake types leading to a total number of 24 systems. The most common approach for the setting of reference conditions, used in seventeen systems, was the utilisation of fish communities in comparably undisturbed natural lakes as reference. Eleven used expert judgment, nine historical data and eight modelled relationships. Fourteen systems combined at least two approaches. The most common fish sampling method was a standardized fishing procedure with multimesh-gillnets. Many countries applied combinations of fishing methods, e.g. non-standard gillnets, fyke nets and electrofishing. Altogether 177 metrics were used for index development and each system combined 2-13 metrics. The most common ones were total standardized catches of number and biomass, relative abundance of Perca fluviatilis, Rutilus rutilus, and Abramis brama, feeding preferences, sensitive species, and non-natives. The pressure-response-relationships for these metrics were supported with both correlations established during system development and scientific publications. However, the metrics and their combinations were highly diverse and no metric was applied universally. Our analysis reveals that most fish-based assessment systems address multiple pressures (eutrophication, hydromorphological alterations, fishery pressure and occurrence of non-natives), whilst few are pressure-specific, tackling only eutrophication or acidification. We argue that the value of fish-based systems for lakes lies in their capacity to capture the effect of many different pressures and their interactions which is lacking for most assessment systems based on other biota.


Assuntos
Lagos , Percas , Animais , Ecossistema , Monitoramento Ambiental , Eutrofização , Pesqueiros , Peixes
4.
Sci Total Environ ; 806(Pt 4): 151267, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34715227

RESUMO

The bioaccumulation of cyclic volatile methylsiloxanes (D3 to D6) as well as linear siloxanes (L3 to L5) was studied in a food web in the St. Lawrence River downstream of the effluent of the municipal wastewater treatment plant in Montreal, Canada. For most species, differences in δ15N in fish and prey showed a clear separation of individual fish feeding in food webs influenced by the wastewater plume from those feeding outside the plume. Cyclic siloxanes were detected in all biotic samples from the individuals identified as feeding in the effluent plume. Siloxane D5 accounted for more than 80% of the total siloxanes. Linear siloxane L5 was also abundant in walleye and gull eggs. Total siloxane concentrations in suspended sediments were 17.3 times higher than in surface sediments in the region of the river in the effluent plume. Caged freshwater mussels (Elliptio sp.), placed in the effluent plume, bioaccumulated 43 times more total siloxanes than PBDEs in 30 days, demonstrating how readily siloxanes are taken up in biota and what a significant component of the contaminant body burden they can account for. The sediment-biota accumulation factors (BSAF) for total siloxanes (∑ D3 to D6 and L3 to L5) showed values of 65.4, 27.8, 9.9 and 6.4 for walleye, northern pike, yellow perch and round goby respectively.


Assuntos
Percas , Poluentes Químicos da Água , Animais , Bioacumulação , Monitoramento Ambiental , Humanos , Siloxanas/análise , Águas Residuárias , Poluentes Químicos da Água/análise
5.
Zootaxa ; 4996(3): 513-524, 2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34810512

RESUMO

A new splendid perch, Grammatonotus bianchi sp. nov. is described on the basis of two specimens (45.968.7 mm SL) collected at 184 m depth in the Andaman Sea off the coast of Myanmar during bottom surveys conducted by the R/V Dr Fridtjof Nansen in 2018. The new species can be distinguished from all congeners by its large head (37.738.6% SL), large orbit (14.415.3% SL), caudal-fin shape, and fresh coloration. A key to Indian Ocean species of Grammatonotus is provided.


Assuntos
Percas , Perciformes , Animais , Oceano Índico , Mianmar , Cauda
6.
Zootaxa ; 4996(1): 49-82, 2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34810545

RESUMO

Three new species of anthiadine species are described from specimens trawled from Australian waters. Pseudanthias paralourgus n. sp. is described from five specimens collected off southeastern Queensland. It resembles P. elongatus (Franz, 1910) from Japan to the South China Sea, but differs in male live coloration. The remaining two species are assigned to the genus Tosana Smith Pope, 1906, which is newly diagnosed to include the two new species and the type species from southern Japan to the South China Sea, T. niwae Smith Pope, 1906. The two new species, T. dampieriensis n. sp. described from three specimens from off Western Australia and T. longipinnis n. sp. described from 42 specimens from off eastern Australia, differ from each other and from T. niwae in various meristic and morphometric details. Pseudanthias paralourgus co-occurs with T. longipinnis. Molecular phylogenetic analysis of mitochondrial COI yielded a tree with the three Tosana species forming the sister group of a clade consisting of P. paralourgus n. sp., P. elongatus and the type species of Pseudanthias Bleeker, 1871, P. pleurotaenia (Bleeker, 1857). Our preliminary phylogenetic analyses suggest that Pseudanthias comprises a polyphyletic assemblage of species that also includes Nemanthias Smith, 1954, Luzonichthys Herre, 1936, Tosanoides Kamohara, 1953, Odontanthias Bleeker, 1873, and Serranocirrhitus Watanabe, 1949, thus highlighting the need for a revised generic classification of species currently assigned to Pseudanthias.


Assuntos
Bass , Percas , Animais , Austrália , Peixes , Masculino , Filogenia
7.
Aquat Toxicol ; 240: 105984, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34627023

RESUMO

Hydroxylated polybrominated diphenyl ethers (OH-PBDEs), naturally produced by algae and cyanobacteria in the Baltic Sea, are potent disrupters of energy metabolism as well as endocrine disruptors and neurotoxins. In this study, European perch (Perca fluviatilis) from the Baltic Sea were sampled from May until October. OH-PBDEs and ten biomarkers were measured in each individual (n = 84 over 18 sampling time points) to study potential correlations between exposure to OH-PBDEs and changes in biomarkers. Several biomarkers showed significant non-linear seasonal variation. In the perch, ethoxyresorufin-O-deethylase (EROD) activity, plasma lactate concentration, and plasma glucose concentration showed a significant positive log-linear correlation with OH-PBDEs, whereas lipid percentage and liver somatic index showed a significant negative log-linear correlation with OH-PBDEs. These results strengthen the concern that OH-PBDEs could cause negative health effects for fish in the Baltic Sea.


Assuntos
Percas , Poluentes Químicos da Água , Animais , Biomarcadores , Monitoramento Ambiental , Éteres Difenil Halogenados/análise , Estações do Ano , Poluentes Químicos da Água/toxicidade
8.
Ecotoxicol Environ Saf ; 226: 112790, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34653840

RESUMO

The organophosphorus (OP) and carbamate (CB) insecticides are responsible for inhibition of the Acetylcholinesterase (AChE) enzyme. The AChE activity, therefore, has been demonstrated to be a potent biomarker for these insecticides in terrestrial and aquatic environments. The objective of this study was to investigate the response of AChE in the brain of four-week old fingerlings of silver perch, Bidyanus bidyanus exposed to OP and CB insecticides. The fish fingeling were exposed to three OPs and one CB insecticide as individual and their binary mixtures for 48 h. The OP insecticides with oxon (PO) as well as thion (PS) group gets oxidized to oxon analogs in biological systems. The 50% AChE inhibition (48 h EC50) in fingerling exposed to chlorpyrifos (CPF) and triazophos (TRZ) was evident at 2.3 and 6.7 µg/L, respectively. The toxicological interaction of three OPs and one CB insecticide was evaluated using the toxic unit method. A strong synergism was observed for binary combination of CPF with profenofos (PRF), and CPF with TAZ. In contrast, the mixture of TAZ with PRF and carbofuran (CBF) with CPF and PRF showed antagonistic behavior. Although OP and CB insecticides can break down rapidly in the environment, this study suggests that non-target aquatic biota may be exposed to mixtures of ChE-inhibiting insecticides for a period of several months, in agricultural regions where insecticides are applied for extended periods of the year. And at environmentally relevant concentrations such mixtures may lead to deleterious effects in non-target organisms.


Assuntos
Clorpirifos , Inseticidas , Percas , Acetilcolinesterase , Animais , Clorpirifos/toxicidade , Inibidores da Colinesterase/toxicidade , Inseticidas/toxicidade
9.
J R Soc Interface ; 18(183): 20210445, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34665974

RESUMO

A long-term, yet detailed view into the social patterns of aquatic animals has been elusive. With advances in reality mining tracking technologies, a proximity-based social network (PBSN) can capture detailed spatio-temporal underwater interactions. We collected and analysed a large dataset of 108 freshwater fish from four species, tracked every few seconds over 1 year in their natural environment. We calculated the clustering coefficient of minute-by-minute PBSNs to measure social interactions, which can happen among fish sharing resources or habitat preferences (positive/neutral interactions) or in predator and prey during foraging interactions (agonistic interactions). A statistically significant coefficient compared to an equivalent random network suggests interactions, while a significant aggregated clustering across PBSNs indicates prolonged, purposeful social behaviour. Carp (Cyprinus carpio) displayed within- and among-species interactions, especially during the day and in the winter, while tench (Tinca tinca) and catfish (Silurus glanis) were solitary. Perch (Perca fluviatilis) did not exhibit significant social behaviour (except in autumn) despite being usually described as a predator using social facilitation to increase prey intake. Our work illustrates how methods for building a PBSN can affect the network's structure and highlights challenges (e.g. missing signals, different burst frequencies) in deriving a PBSN from reality mining technologies.


Assuntos
Carpas , Percas , Animais , Ecossistema , Água Doce , Comportamento Predatório
10.
Biol Lett ; 17(10): 20210388, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34610252

RESUMO

Anticipatory behaviour is the expectation of a near-future event based on information processed in the past and influences an animal's tactical decisions, particularly when there are significant fitness consequences. The grass lizard (Takydromus viridipunctatus) perches on blades of grass at night which likely reduces the probability of predation by terrestrial predators such as snakes, rodents and shrews. During twilight (starting 30 min before sunrise), they move from above the grass to within grass clumps and this is thought to afford the lizard protection while reducing detection by avian predators. Here, we examined how lizards shift their behaviour as a function of visual detectability to their primary predator, the cattle egret (Bubulcus ibis). We show that the lizards shift from their perch site during twilight at the earliest time at which egrets depart communal roosts. At the same time, visual modelling shows a dramatic increase in the detectability of the lizards to the visual system of egrets. Therefore, anticipatory behaviour in response to environmental cues acts to reduce predation risk as lizards become more conspicuous and predators become more active. Grass lizard anticipatory behaviour appears to be finely tuned by natural selection to adjust to temporal changes in predation risk.


Assuntos
Lagartos , Percas , Animais , Aves , Bovinos , Comportamento Predatório , Serpentes
11.
Artigo em Inglês | MEDLINE | ID: mdl-34501623

RESUMO

This paper describes the study of the fatty acid (FA) composition of three fish species (roach, perch, and pike) from Lake Gusinoe (western Transbaikalia). Using principal component analysis, the fatty acid composition of the studied fish species was shown to be species specific. The muscle tissue of roach, perch, and pike was found to contain high levels of polyunsaturated fatty acids (PUFA), including essential docosahexaenoic (DHA), eicosapentaenoic (EPA), and arachidonic acids. Indicators of nutritional quality based on the fatty acid composition showed that the values of the hypocholesterolemic/hypercholesterolemic (HH) ratio indices were sufficiently high. The atherogenicity (AI) and thrombogenicity (TI) indices, which are indicators for the nutritional value, were less than 1 in the studied fish. In terms of flesh lipid quality (FLQ), pike and perch had the highest proportion of total EPA + DHA. According to the obtained data for the composition of fatty acids in the muscle tissue of the studied fish from Lake Gusinoe, the anthropogenic load exerted on Lake Gusinoe has not yet statistically significantly affected the fish muscle quality.


Assuntos
Percas , Animais , Esocidae , Ácidos Graxos , Ácidos Graxos Insaturados , Lagos
12.
PLoS One ; 16(9): e0257882, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34591910

RESUMO

Angler trip success and catch rates are dependent upon a fishes' vulnerability to angling. Angling vulnerability can be influenced by angler-specific attributes (i.e., bait choice, lure size, use of a guide), and individual fish traits (i.e., boldness, aggression, stress responsiveness, and memory retention). The mechanisms that function in a fishes' angling vulnerability, and contribute to catch rate, are likely correlated with environmental factors however, the influence of environmental factors on angling vulnerability are not well understood. We used the long-term (1946 -present) compulsory creel dataset from Escanaba Lake, WI, USA to test for interactions between angling vulnerability (i.e., angler trip success and catch rates) and environmental factors to better understand these dynamics in recreational fisheries. Our objective was to test for the influence of angler associated variables and environmental factors on open water angler trip success (i.e., catch ≥ one fish) and catch rate of walleye Sander vitreus and muskellunge Esox masquinongy during 2003-2015 using a hurdle model approach. Fishing trip success and catch rates for both species were most strongly influenced by angler-related variables (i.e., guide status, bait type, the proportion of the fish population previously caught). Environmental factors associated with lower light intensity (i.e., diel period, mean daily solar radiation, solar-Julian day interaction) had a positive influence on walleye vulnerability. Lower air temperatures and lunar position (moon overhead or underfoot) and phase (gibbous' and full moon) also had a positive effect on walleye angling. Muskellunge trip success and catch rate were positively influenced by light metrics (i.e., diel period and mean daily solar radiation) and increased with air temperature. Lunar variables (position and phase), as well as wind speed and direction also influenced muskellunge angling vulnerability. A better understanding of the influence of environmental factors on angling vulnerability is an important component of fisheries management as management goals focus on balancing fish populations and creating satisfactory catch rates to enhance the angling experience. Our results suggest that angler-specific variables, light, temperature, lunar, and weather conditions influenced species-specific angling vulnerability for walleye and muskellunge.


Assuntos
Conservação dos Recursos Naturais/métodos , Esocidae/fisiologia , Percas/fisiologia , Animais , Pesqueiros , Atividades Humanas , Humanos , Modelos Biológicos , Recreação , Temperatura , Tempo (Meteorologia)
13.
Arch Environ Contam Toxicol ; 81(4): 621-636, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34562110

RESUMO

We conducted acute toxicity studies using semi-static protocols to examine the lethal responses of Australian bass and silver perch exposed to antimony (Sb) oxidation states in Sb(III) (10.5-30.5 mg L-1) and Sb(V) (95.9-258.7 mg L-1). Bioavailability and the effects of Sb on body ion regulation (Na, Ca, Mg, and K) were also investigated. Antimony species-specific effects were observed with exposure to both Sb oxidation states. Median lethal concentrations (LC50s) for Sb(III) were 13.6 and 18 mg L-1 for Australian bass and silver perch, respectively, and the LC50 for Sb(V) in Australian bass was 165.3 mg L-1. The LC50 could not be calculated for silver perch exposed to Sb(V) as the maximum exposure concentrations produced 40% mortality but a larger-than value of > 258.7 mg L-1 was estimated. Relative median potency values derived from the LC50s were 0.1 Sb(III) and 12.2 and 16.6 Sb(V) for Australian bass and silver perch, respectively, demonstrating greater toxicity of Sb(III) to both fish species. Antimony uptake in fish was observed. Median critical body residue (CBR50) values of 77.7 and 26.6 mg kg-1 for Sb(III) were estimated for Australian bass and silver perch, respectively, and 628.1 mg kg-1 for Sb(V) in Australian bass. Bioconcentration factors (BCFs) for both Sb(III) and Sb(V) did not change with exposure but the greater BCFs for fish exposed to Sb(III) indicate that it is more bioavailable than Sb(V) in acute exposure. No effects on whole-body Na, Ca, Mg, or K ions were observed with fish exposure to either Sb species.


Assuntos
Bass , Percas , Animais , Antimônio/toxicidade , Austrália , Água Doce , Homeostase
14.
Cells ; 10(9)2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-34571938

RESUMO

Promising efforts are ongoing to extend genomics resources for pikeperch (Sander lucioperca), a species of high interest for the sustainable European aquaculture sector. Although previous work, including reference genome assembly, transcriptome sequence, and single-nucleotide polymorphism genotyping, added a great wealth of genomic tools, a comprehensive characterization of gene expression across major tissues in pikeperch still remains an unmet research need. Here, we used deep RNA-Sequencing of ten vital tissues collected in eight animals to build a high-confident and annotated trancriptome atlas, to detect the tissue-specificity of gene expression and co-expression network modules, and to investigate genome-wide selective signatures in the Percidae fish family. Pathway enrichment and protein-protein interaction network analyses were performed to characterize the unique biological functions of tissue-specific genes and co-expression modules. We detected strong functional correlations and similarities of tissues with respect to their expression patterns-but also significant differences in the complexity and composition of their transcriptomes. Moreover, functional analyses revealed that tissue-specific genes essentially play key roles in the specific physiological functions of the respective tissues. Identified network modules were also functionally coherent with tissues' main physiological functions. Although tissue specificity was not associated with positive selection, several genes under selection were found to be involved in hypoxia, immunity, and gene regulation processes, that are crucial for fish adaption and welfare. Overall, these new resources and insights will not only enhance the understanding of mechanisms of organ biology in pikeperch, but also complement the amount of genomic resources for this commercial species.


Assuntos
Regulação da Expressão Gênica , Redes Reguladoras de Genes , Percas/metabolismo , Mapas de Interação de Proteínas , Seleção Genética , Transcriptoma , Animais , Genoma , Anotação de Sequência Molecular , Especificidade de Órgãos , Percas/genética
15.
Artigo em Inglês | MEDLINE | ID: mdl-34574365

RESUMO

BACKGROUND: The Ruff 2 and 7 Selective Attention Test (RSAT) is designed to measure selective attention. It tests automatic detection speed (ADS), automatic detection errors (ADE), automatic detection accuracy (ADA), controlled search speed (CSS), controlled search errors (CSE), and controlled search accuracy (CSA). The purpose of this study was to examine the test-retest reliability, practice effect, and minimum detectable change (MDC) of the RSAT in patients with schizophrenia. METHODS: A total of 101 patients with schizophrenia completed the RSAT twice at a 4-week interval. The intra-class correlation coefficient (ICC), paired t test, and effect size were used to examine the test-retest reliability and practice effect. The standard error of measurement (SEM) and MDC were calculated. RESULTS: The difference scores between the two assessments were significant in all the indexes. The absolute effect sizes were 0.14 to 0.30. The ICCs of the RSAT ranged from 0.69 to 0.91. The MDC% in the indexes of ADS, ADA, and CSA of the RSAT were <30%. CONCLUSIONS: The RSAT is reliable for assessing selective attention in patients with schizophrenia. The RSAT has good to excellent test-retest reliability, a trivial to small practice effect, and indexes of ADS, ADA, and CSA, representing acceptable random measurement error.


Assuntos
Percas , Esquizofrenia , Animais , Atenção , Humanos , Reprodutibilidade dos Testes , Esquizofrenia/diagnóstico
16.
Sci Rep ; 11(1): 16272, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34381143

RESUMO

The objective of the present study was to compare skeletal muscle proteomic profiles, histochemical characteristics, and expression levels of myogenic regulatory factors (MRFs) between fast- versus slow-growing yellow perch Perca flavescens and identify the proteins/peptides that might play a crucial role in the muscle growth dynamic. Yellow perch were nursed in ponds for 6 weeks from larval stage and cultured in two meter diameter tanks thereafter. The fingerlings were graded to select the top 10% and bottom 10% fish which represented fast- and slow-growing groups (31 yellow perch per each group). Our statistical analyses showed 18 proteins that had different staining intensities between fast- and slow-growing yellow perch. From those proteins 10 showed higher expression in slow-growers, and 8 demonstrated higher expression in fast-growers. Fast-growing yellow perch with a greater body weight was influenced by both the muscle fiber hypertrophy and mosaic hyperplasia compared to slow-growing fish. These hyperplastic and hypertrophic growth in fast-grower were associated with not only metabolic enzymes, including creatine kinase, glycogen phosphorylase, and aldolase, but also myoD and myogenin as MRFs. Overall, the results of the present study contribute to the identification of different expression patterns of gene products in fast- and slow-growing fish associated with their muscle growth.


Assuntos
Expressão Gênica , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/metabolismo , Percas/anatomia & histologia , Percas/genética , Proteômica , Animais , Creatina Quinase/metabolismo , Frutose-Bifosfato Aldolase/metabolismo , Glicogênio Fosforilase/metabolismo , Músculo Esquelético/crescimento & desenvolvimento , Fatores de Regulação Miogênica/genética , Fatores de Regulação Miogênica/metabolismo , Percas/crescimento & desenvolvimento , Percas/metabolismo
17.
J Comp Physiol B ; 191(5): 881-894, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34373935

RESUMO

It is well known that carnivorous fish cannot use plant-proteins efficiently. They affect lipid metabolism of fish and cause serious problems to fish health. The reasons for this deficiency of fish metabolism are not known well. Chinese perch, a carnivorous fish, can accept artificial diet after domestication and is also considered as a novel model of fish for nutrition studies. Therefore, the aim of this study was to explore the effect of fish meal replacement by low- or high-rapeseed meal on lipid and glucose metabolism of Chinese perch. Three experimental diets were formulated with 0, 10%, and 30% rapeseed meal, named as Control, RSL, and RSH groups, respectively. After 8-weeks of the feeding trial, the inhibition of growth and fat deposition were observed in Chinese perch fed with rapeseed meal diets compared to the control group. Fish fed with RSL diets showed decreased food intake, serum low density lipoprotein (LDL), phosphorylated Grb10 (P < 0.05), inhibited fatty acid (FA) transport (lipoprotein lipase (LPL)), and glycerol synthesis (phosphoenol pyruvate carboxykinase (PEPCK)) in the liver. In addition, fish fed with RSL diets were also inhibited FA synthesis (fatty acid synthase (FAS), sterol regulatory element binding protein 1 (SREBP1), and Acetyl-CoA carboxylase (ACC1)), lipid uptake (hepatic lipase (HL)), ß-oxidation (carnitine palmitoyltransferase I (CPT1)), and glycerol synthesis (PEPCK) in the visceral adipose tissue. Fish fed with RSH diets showed phosphorylated AMPK, inhibited FA synthesis (SREBP1, ACC1, and FAS), while enhanced lipolysis (hormone-sensitive lipase (HSL)), and then reduced Acetyl-CoA pool. In turn, ß-oxidation (peroxisome proliferator-activated receptor-a (PPARα) and CPT1) was inhibited, while glycolysis (glucose-6-phosphatase (G6PD) and pyruvate carboxylase (PC)) were enhanced, consequently the lipid accumulation was decreased in the liver. Fish were also inhibited lipid uptake (LPL), that caused inhibiting of FA synthesis (SREBP1), ß-oxidation (CPT1), glycerol synthesis (PEPCK), and in turn improved lipolysis (HSL) in the visceral adipose tissue. Our study suggested that both RSL and RSH diets decreased lipid accumulation in Chinese perch; however, the mechanism of lipid metabolism was different. Fish accepted less diet in RSL group, which inhibited lipid metabolism in the liver and in the visceral adipose tissues, while fish in RSH group activated AMPK pathway, inhibited FA synthesis, and enhanced lipolysis, which reduced Acetyl-CoA pool in the liver. Subsequently, lipid uptake and metabolism were inhibited in the visceral adipose tissue of RSH fish.


Assuntos
Brassica napus , Percas , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Brassica napus/metabolismo , China , Dieta/veterinária , Metabolismo dos Lipídeos , Fígado/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo
18.
Animal ; 15(9): 100340, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34450509

RESUMO

This study aimed to assess the effect of constant darkness applied to fish during controlled breeding on reproductive traits in domesticated females of Eurasian perch. Based on the assumption that keeping fish in constant darkness during the reproduction operation may reduce stress, suspected to be responsible for variable spawning effectiveness in this species. Two conditions were assessed (16 h light per day [group 16L] and constant darkness [group 0L], two tank replicates per condition). The reproductive protocol involved a 7-day-long adaptation period for group 0L where photoperiod was reduced by 2.3 h a day down to constant darkness. After the adaptation period, two hormone injections (salmon gonadoliberin analogue) were applied to both groups: priming (10 µg/kg) and resolving (25 µg/kg) with a 7-day interval between them. During the study, morphometric indices were recorded and blood, brain, and pituitary samples were collected to assess stress markers and determine hypothalamic-pituitary-gonadal axis functioning via measuring blood plasma hormones, as well as gonadoliberin and gonadotropins (luteinising hormone [LH] and follicle-stimulating hormone [FSH]) transcript abundance (n = 7 for each group at each sampling point). In addition, kinetics of the final oocyte maturation (FOM) process, ovulation rate, and egg quality of each group was monitored (n = 12 for each group). The results indicated that there were no differences in terms of morphometry, FOM kinetics, and most stress indices between groups throughout the experiment, except haematocrit, which increased immediately following the acclimation period in fish kept in darkness. Constant darkness negatively affected plasma levels of 17α,20ß-dihydroxy-4-pregnen-3-one (DHP) and LH transcript expression at the time of the second hormone injection. This indicated that exposure to constant darkness negatively affected priming of the hormonal dose applied, resulted in the disruption of ovulation, and reduced ovulation rates (50%) for group 0L, as compared to 16L (91%). The findings of this study clearly indicate that constant darkness may have significant deleterious effects on reproductive traits throughout out-of-season induced, hormonally supported, controlled reproduction. Therefore, we advise against the use of constant darkness when managing broodstock reproduction in domesticated Eurasian perch.


Assuntos
Percas , Animais , Escuridão , Feminino , Hormônio Liberador de Gonadotropina , Gonadotropinas , Reprodução
19.
Ecotoxicol Environ Saf ; 222: 112495, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34265536

RESUMO

The environment contains a multitude of man-made chemicals, some of which can act as endocrine disruptors (EDCs), while others can be immunotoxic. We evaluated thyroid disruption and immunotoxic effects in wild female perch (Perca fluviatilis) collected from two contaminated areas in Sweden; one site contaminated with per- and polyfluoroalkyl substances (PFASs) and two sites contaminated with polychlorinated biphenyls (PCBs), with one reference site included for each area. The hepatic mRNA expression of thyroid receptors α and ß, and the thyroid hormone metabolising iodothyronine deiodinases (dio1, dio2 and dio3) were measured using real-time PCR, while the levels of thyroid hormone T3 in plasma was analysed using a radioimmunoassay. In addition, lymphocytes, granulocytes, and thrombocytes were counted microscopically. Our results showed lower levels of T3 as well as lower amounts of lymphocytes and granulocytes in perch collected from the PFAS-contaminated site compared to reference sites. In addition, expressions of mRNA coding for thyroid hormone metabolising enzymes (dio2 and dio3) and thyroid receptor α (thra) were significantly different in these fish compared to their reference site. For perch collected at the two PCB-contaminated sites, there were no significant differences in T3 levels or in expression levels of the thyroid-related genes, compared to the reference fish. Fish from one of the PCB-contaminated sites had higher levels of thrombocytes compared with both the second PCB lake and their reference lake; hence PCBs are unlikely to be the cause of this effect. The current study suggests that lifelong exposure to PFASs could affect both the thyroid hormone status and immune defence of perch in the wild.


Assuntos
Fluorcarbonetos , Percas , Bifenilos Policlorados , Poluentes Químicos da Água , Animais , Feminino , Humanos , Lagos , Bifenilos Policlorados/análise , Bifenilos Policlorados/toxicidade , Glândula Tireoide/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
20.
Arch Virol ; 166(9): 2627-2632, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34255185

RESUMO

In this study, a novel picornavirus (perchPV/M9/2015/HUN, GenBank accession no. MW590713) was detected in eight (12.9%) out of 62 faecal samples collected from three (Perca fluviatilis, Sander lucioperca, and Ameiurus melas) out of 13 freshwater fish species tested and genetically characterized using viral metagenomics and RT-PCR methods. The complete genome of perchPV/M9/2015/HUN is 7,741 nt long, excluding the poly(A) tail, and has the genome organization 5'UTRIRES-?/P1(VP0-VP3-VP1)/P2(2A1NPG↓P-2A2H-box/NC-2B-2C)/P3(3A-3BVPg-3CPro-3DPol)/3'UTR-poly(A). The P1, 2C, and 3CD proteins had 41.4%, 38.1%, and 47.3% amino acid sequence identity to the corresponding proteins of Wenling lepidotrigla picornavirus (MG600079), eel picornavirus (NC_022332), and Wenling pleuronectiformes picornavirus (MG600098), respectively, as the closest relatives in the genus Potamipivirus. PerchPV/M9/2015/HUN represents a potential novel fish-origin species in an unassigned genus in the family Picornaviridae.


Assuntos
Ictaluridae/virologia , Percas/virologia , Filogenia , Infecções por Picornaviridae/veterinária , Infecções por Picornaviridae/virologia , Picornaviridae/classificação , Picornaviridae/isolamento & purificação , Regiões 3' não Traduzidas , Regiões 5' não Traduzidas , Sequência de Aminoácidos , Animais , Fezes/virologia , Água Doce , Genoma Viral , Hungria , Picornaviridae/genética , RNA Viral/genética , Análise de Sequência , Proteínas Virais/genética
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