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1.
Braz. J. Biol. ; 83: 1-18, 2023. mapas, ilus, tab, graf
Artigo em Inglês | VETINDEX, VETINDEX | ID: vti-765565

RESUMO

This study was conducted to estimate the diversity and the occurrence of commercially important finfish species collected by twenty fish sampling site of Sindh and Baluchistan coasts of the Arabian Sea in Pakistan from January to December 2019. Additionally, physicochemical characteristics of seawater were analyzed from these selected sites and found to be within suitable ranges required for fish growth and survive. A total of 81287 fish individuals were collected and identified as 49 species belonging to 26 families in our study. The most diversified family was Sparidae (13 species) followed by Carangidae and Lutjanidae (4 species), Mullidae, Serranidae, Ariidae (3 species), and Sciaenidae (2 species). The remaining 20 families were represented by only one species. The values of Shannon diversity index calculated for the four selected habitats revealed that high fish diversity was reported at Sonmiani Coast (H=1.81), while less at Ormara Coast (H=0.23). Likewise, Evenness index (E) was high at Sonmiani Coast (E=0.50) and less fish diversity was reported at Ormara Coast (E=0.06). Reducing risks to threatened marine species in coastal habitats also requires conservation actions at multiple scales. Thus, it was concluded that our study could be valuable in providing the more informations regarding to the diversity of finfish species and their occurrence along the Pakistan Coast. Further, to better understand the effects, regular monitoring and conservation measures should be taken to mitigate the influence of anthropogenic activities and protect finfish diversity from further decline.(AU)


Este estudo foi conduzido para estimar a diversidade e a ocorrência de espécies de peixes comercialmente importantes coletadas por vinte locais de amostragem de peixes nas costas de Sindh e Baluchistão do mar da Arábia, no Paquistão, de janeiro a dezembro de 2019. Além disso, as características físico-químicas da água do mar foram analisadas a partir desses peixes locais selecionados e considerados dentro dos intervalos adequados necessários para o crescimento e sobrevivência dos peixes. Um total de 8.1287 indivíduos de peixes foi coletado e identificado como 49 espécies pertencentes a 26 famílias em nosso estudo. A família mais diversificada foi Sparidae (13 espécies), seguida por Carangidae e Lutjanidae (4 espécies), Mullidae, Serranidae, Ariidae (3 espécies) e Sciaenidae (2 espécies). As 20 famílias restantes foram representadas por apenas uma espécie. Os valores do índice de diversidade de Shannon calculados para os quatro habitats selecionados revelaram que uma alta diversidade de peixes foi relatada na costa Sonmiani (H = 1,81), enquanto menos na costa Ormara (H = 0,23). Da mesma forma, o índice de regularidade (E) foi alto na costa de Sonmiani (E = 0,50) e menos diversidade de peixes foi relatada na costa de Ormara (E = 0,06). A redução dos riscos para as espécies marinhas ameaçadas em habitats costeiros também requer ações de conservação em várias escalas. Assim, concluiu-se que nosso estudo pode ser valioso para fornecer mais informações sobre a diversidade de espécies de peixes finos e sua ocorrência ao longo da costa do Paquistão. Além disso, para compreender melhor os efeitos, medidas regulares de monitoramento e conservação devem ser tomadas para mitigar a influência das atividades antropogênicas e proteger a diversidade de peixes finos de um declínio maior.(AU)


Assuntos
Animais , Biodiversidade , Peixes/classificação , Peixes/crescimento & desenvolvimento , Água do Mar/química , Fenômenos Químicos
2.
Braz. J. Biol. ; 83: 1-5, 2023. mapas, tab
Artigo em Inglês | VETINDEX, VETINDEX | ID: vti-765542

RESUMO

This study estimated the length–weight relationships of 16 fish species occurring close to the shores of sandy beaches along the lower Negro River basin, Brazilian Amazon. The specimens were captured for one day each month, in October to November 2016, early in the morning and early evening, using trawl net (20 m length and 3.5 m height, 5 mm mesh between opposite knots). Measurements were taken for standard length (SL 0.1 cm precision) and total weight (TW 0.01 g precision). The parameters a and b of the equation WT = a.LTb were estimated. The a values ranged from 0.0018 to 0.0226 and b values ranged from 2.5271 to 3.3244. This study also provides new data on of maximum lengths for six species, Amazonsprattus scintilla, Brycon pesu, Moenkhausia megalops, Pachyurus paucirastrus, Reganella depressa and Trachydoras microstomus, and new reports of the LWRs parameters of 15 fish species.(AU)


Este estudo estimou as relações comprimento-peso de 16 espécies de peixes que ocorrem às margens de praias arenosas ao longo da bacia do baixo Rio Negro, Amazônia brasileira. As espécies foram capturadas durante um dia de cada mês, de outubro a novembro de 2016, no início da manhã e no início da noite, usando rede de cerco (20 m de comprimento e 3,5 m de altura, 5 malha mm entre nós opostos). As medidas foram feitas para comprimento padrão (SL - precisão de 0,1 cm) e peso total (TW - precisão de 0,01 g). Os parâmetros a e b da equação WT = a.LTb foram estimados. Os valores de a variaram de 0,0018 a 0,0226 e os valores de b variaram de 2,5271 a 3,3244. Este estudo também fornece novos dados sobre comprimentos máximos para seis espécies, Amazonsprattus scintilla, Brycon pesu, Moenkhausia megalops, Pachyurus paucirastrus, Reganella depressa e Trachydoras microstomus, e novos reportes dos parâmetros da LWRs de 15 espécies de peixes.(AU)


Assuntos
Animais , Peixes/anatomia & histologia , Peixes/crescimento & desenvolvimento
3.
Braz. J. Biol. ; 83: 1-10, 2023. mapas, tab, graf, ilus
Artigo em Inglês | VETINDEX, VETINDEX | ID: vti-765404

RESUMO

The colonization pattern of fish assemblages in streams is often studied in the context of environmental filters. On the other hand, when fish assemblages are subjected to anthropogenic effects, variables associated with environmental quality assume more importance. Therefore, this work evaluated the richness and composition of fish from streams sampled at different urbanization levels, aiming to determine any direct effects on the structure of fish assemblages. To accomplish this, samples were collected from 2003 to 2011 at 31 sites distributed among 3 microbasins in the Rio Ivinhema Basin, Alto Rio Paraná. Based on environmental variables, physicochemical of the water and analysis of the use and occupation of the soil, the microbasins were classified into different urbanization levels (low, medium and high). A total of 4,320 individuals were sampled, out of which 57 fish species were recorded. Sampled sites with medium urbanization level presented higher richness compared to sampled sites with high urbanization level which presented lower richness. Species richness in these sites was explained mainly by water temperature and water velocity. Results confirmed that urbanization does directly affect environmental integrity, which, in turn, can lead to the homogenization of stream assemblages.(AU)


Estudos sobre assembleias de peixes em riachos enfatizam o papel dos filtros ambientais associados ao padrão de colonização das assembleias, por outro lado, quando a assembleia está sujeita aos efeitos antropogênicos, as variáveis ambientais associadas à qualidade ambiental assumem maior importância. Dessa forma, o objetivo deste estudo foi analisar a riqueza e a composição de peixes de riachos amostrados em diferentes níveis de urbanização, buscando evidenciar se o efeito reflete diretamente na estrutura das assembleias. As amostragens foram realizadas em 31 locais distribuídos em três microbacias na bacia Rio Ivinhema, Alto Rio Paraná, no período de 2003 a 2011. Com base nas variáveis ambientais, físico-químicos da água e análise do uso e ocupação do solo as microbacias foram classificadas em diferentes níveis de urbanização (baixo, médio e alto). Foram amostrados um total 4.320 indivíduos, dos quais foram registradas 57 espécies de peixes. Os locais amostrados com influência média da urbanização apresentaram maior riqueza de espécies, entretanto, os locais amostrados com alta influência da urbanização apresentaram menor riqueza de espécies. Dessa forma, constatamos que a urbanização influencia diretamente na integridade ambiental, que pode levar a homogeneização das assembleias de riachos.(AU)


Assuntos
Animais , Peixes/classificação , Peixes/crescimento & desenvolvimento , Bacias Fluviais/análise , Urbanização , Água/análise , Água/química , Usos do Solo , Análise do Solo , Poluição Ambiental/análise
4.
Int J Mol Sci ; 23(1)2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35008920

RESUMO

The objective of the present research was to study the effect of cold shock (3 °C and 6 °C) on fertilized eggs of the sterlet, Acipenser ruthenus L. Cold shock was applied for various durations (30, 60 and 90 min) and the ploidy levels, survival, and genotypes of the treated embryos/larvae were recorded. Analysis of ploidy levels confirmed the presence of diploid, triploid, and mosaic (1n/2n, 2n/3n, and 1n/2n/3n) genotypes in experimental groups, while it was strictly diploid in control groups. Microsatellite genotyping confirmed both the incidence of polyspermy and retention of the 2nd polar body in experimental groups. However, patterns of inheritance in all diploid offspring in experimental and control groups revealed classical Mendelian disomic inheritance. Interestingly, the observed mosaic sterlets had normal morphology and were alive. However, some larvae had abnormal morphology which may be due to haploid syndrome. In all treatment groups (treatments: 3 °C-30 min; 3 °C-60 min; 3 °C-90 min; 6 °C-60 min), where the percentage of polyploid/mosaic larvae were high, the mortality was also high. Whereas, in the control groups (where there were only diploid (2n) larvae), the mortality was relatively low.


Assuntos
Resposta ao Choque Frio/fisiologia , Peixes/crescimento & desenvolvimento , Peixes/genética , Ploidias , Alelos , Animais , Segregação de Cromossomos , Desenvolvimento Embrionário , Peixes/embriologia , Larva/crescimento & desenvolvimento , Repetições de Microssatélites/genética , Análise de Sobrevida
5.
PLoS One ; 17(1): e0262357, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34982802

RESUMO

To date, more than 2400 valid fish species have been recorded in the Amazon basin. However, some regions remain poorly documented. This is the case in the Beni basin and in particular in one of its main sub-basins, the Tuichi, an Andean foothills rivers flowing through the Madidi National Park in the Bolivian Amazonia. The knowledge of its ichthyological diversity is, however, essential for the management and protection of aquatic ecosystems, which are threatened by the development of infrastructures (dams, factories and cities), mining and deforestation. Environmental DNA (eDNA) has been relatively little used so far in the Amazon basin. We sampled eDNA from water in 34 sites in lakes and rivers in the Beni basin including 22 sites in the Tuichi sub-basin, during the dry season. To assess the biogeographical patterns of the amazonian ichthyofauna, we implemented a metabarcoding approach using two pairs of specific primers designed and developed in our laboratory to amplify two partially overlapping CO1 fragments, one of 185bp and another of 285bp. We detected 252 fish taxa (207 at species level) among which 57 are newly identified for the Beni watershed. Species compositions are significantly different between lakes and rivers but also between rivers according to their hydrographic rank and altitude. Furthermore, the diversity patterns are related to the different hydro-ecoregions through which the Tuichi flows. The eDNA approach makes it possible to identify and complete the inventory of the ichthyofauna in this still poorly documented Amazon basin. However, taxonomic identification remains constrained by the lack of reference barcodes in public databases and does not allow the assignment of all OTUs. Our results can be taken into account in conservation and management strategies and could serve as a baseline for future studies, including on other Andean tributaries.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Código de Barras de DNA Taxonômico/métodos , Ecossistema , Monitoramento Ambiental/métodos , Peixes/genética , Animais , Brasil , Peixes/crescimento & desenvolvimento , Estações do Ano
6.
PLoS One ; 17(1): e0262281, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34995331

RESUMO

Ensuring the accuracy of age estimation in fisheries science through validation is an essential step in managing species for long-term sustainable harvest. The current study used Δ14 C in direct validation of age estimation for queen triggerfish Balistes vetula and conclusively documented that triggerfish sagittal otoliths provide more accurate and precise age estimates relative to dorsal spines. Caribbean fish samples (n = 2045) ranged in size from 67-473 mm fork length (FL); 23 fish from waters of the southeastern U.S. (SEUS) Atlantic coast ranged in size from 355-525 mm FL. Otolith-based age estimates from Caribbean fish range from 0-23 y, dorsal spine-based age estimates ranged from 1-14 y. Otolith-based age estimates for fish from the SEUS ranged from 8-40 y. Growth function estimates from otoliths in the current study (L∞ = 444, K = 0.13, t0 = -1.12) differed from spined-derived estimates in the literature. Our work indicates that previously reported maximum ages for Balistes species based on spine-derived age estimates may underestimate longevity of these species since queen triggerfish otolith-based ageing extended maximum known age for the species by nearly three-fold (14 y from spines versus 40 y from otoliths). Future research seeking to document age and growth population parameters of Balistes species should strongly consider incorporating otolith-based ageing in the research design.


Assuntos
Peixes/fisiologia , Membrana dos Otólitos/química , Envelhecimento , Animais , Radioisótopos de Carbono/análise , Pesqueiros , Peixes/anatomia & histologia , Peixes/crescimento & desenvolvimento , Longevidade , Membrana dos Otólitos/anatomia & histologia , Datação Radiométrica
7.
Braz. J. Biol. ; 82: 1-7, 2022. ilus, tab, graf
Artigo em Inglês | VETINDEX, VETINDEX | ID: vti-18689

RESUMO

The present study was conducted for the taxonomic, morphometric and limnological assessment of the commercially important ichthyofauna of Sakhakot Stream, Malakand, Pakistan. The study area was divided into three sites along the water course namely Dargai Stream, Sakhakot Stream and Shergarh Stream. Fish samples were collected randomly during January to August 2017 with the help of fish gears. A taxonomic key was designed for the collected fish specimens. Ten fish species were identified belonging to 3 orders and 4 families. Family Cyprinidae was the dominant family with seven representative species while families Siluridae, Nemacheilidae and Mastacembelidae were represented by one species each. Lower mean total length and standard length was recorded in Puntius conchonius (Hamilton, 1822) as 9.2 ± 0.6 cm and 7.3 ± 0.6 cm respectively, while highest mean total length and standard length was recorded in Mastacembelus armatus (Lacepede, 1800) as 28.1 ± 1.7 cm and 15.9 ± 2.4 cm respectively. Mean pH of the water ranged from 6.1 at Shergarh Stream in August to 8.7 at Sakhakot Stream in January. Average temperature range was recorded from 10.9 °C in January at Dargai Stream to 18.7 °C in August at Shergarh Stream. No statistically significant difference was found for temperature (p = 0.96) and pH (p = 0.14) in the three water streams. The present study will provide a baseline for the rearing and enhancement of wild stock of the commercially important ichthyofauna in the field of aquaculture and fisheries.(AU)


O presente estudo foi realizado para a avaliação taxonômica, morfométrica e limnológica da ictiofauna comercialmente importante do Riacho Sakhakot, Malakand, Paquistão. A área de estudo foi dividida em três locais ao longo do curso de água, nomeadamente Riacho Dargai, Riacho Sakhakot e Riacho Shergarh. As amostras de peixes foram coletadas aleatoriamente durante janeiro e agosto de 2017, com a ajuda de artes de peixes. Uma chave taxonômica foi projetada para os espécimes de peixes coletados. Foram identificadas dez espécies de peixes pertencentes a 3 ordens e 4 famílias. A família Cyprinidae foi a família dominante, com sete espécies representativas, enquanto as famílias Siluridae, Nemacheilidae e Mastacembelidae foram representadas por uma espécie cada. O comprimento total médio mais baixo e o comprimento padrão foram registrados em Puntius conchonius (Hamilton, 1822) como 9.2 ± 0.6 cm e 7.3 ± 0.6 cm, respectivamente, enquanto o comprimento total médio e o comprimento padrão mais altos foram registrados em Mastacembelus armatus (Lacepede, 1800) como 28.1 ± 1.7 cm e 15.9 ± 2.4 cm, respectivamente. O pH médio da água variou de 6.1 no Riacho Shergarh em agosto a 8.7 no Riacho Sakhakot em janeiro. A faixa de temperatura média foi registrada de 10.9 °C em janeiro no Riacho Dargai a 18.7 °C em agosto no Riacho Shergarh. Não foi encontrada diferença estatisticamente significativa para temperatura (p = 0,96) e pH (p = 0,14) nos três cursos de água. O presente estudo fornecerá uma linha de base para a criação e aprimoramento do estoque selvagem da ictiofauna comercialmente importante no campo da aquicultura e pesca.(AU)


Assuntos
Animais , Peixes/anatomia & histologia , Peixes/crescimento & desenvolvimento , Cyprinidae/crescimento & desenvolvimento , Peixes-Gato , Classificação/métodos
8.
Artigo em Inglês | MEDLINE | ID: mdl-34626804

RESUMO

Aquatic hypoxia is both a naturally-occurring and anthropogenically-generated event. Fish species have evolved different adaptations to cope with hypoxic environments, including gill modifications and air breathing. However, little is known about the molecular mechanisms involved in the respiration of embryonic and larval fishes during critical windows of development. We assessed expression of the genes hif-1α, fih-1, nhe1, epo, gr and il8 using the developing tropical gar as a piscine model during three developmental periods (fertilization to hatch, 1 to 6 days post hatch (dph) and 7 to 12 dph) when exposed to normoxia (~7.43 mg/L DO), hypoxia (~2.5 mg/L DO) or hyperoxia (~9.15 mg/L DO). All genes had higher expression when fish were exposed to either hypoxia or hyperoxia during the first two developmental periods. However, fish continuously exposed to hypoxia had increased expression of the six genes by hatching and 6 dph, and by 12 dph only hif-1α still had increased expression. The middle developmental period was the most hypoxia-sensitive, coinciding with several changes in physiology and morphology. The oldest larvae were the most resilient to gene expression change, with little variation in expression of the six genes compared. This study is the first to relate the molecular response of an air-breathing fish to oxygen availability to developmental critical windows and contributes to our understanding of some molecular responses of developing fish to changes in oxygen availability.


Assuntos
Doenças dos Peixes/genética , Peixes/genética , Hiperóxia/veterinária , Hipóxia/veterinária , Animais , Aquicultura , Eritropoetina/genética , Feminino , Doenças dos Peixes/fisiopatologia , Proteínas de Peixes/genética , Peixes/crescimento & desenvolvimento , Peixes/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Hiperóxia/genética , Hiperóxia/fisiopatologia , Hipóxia/genética , Hipóxia/fisiopatologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Interleucina-8/genética , Masculino , Receptores de Glucocorticoides/genética , Fenômenos Fisiológicos Respiratórios , Trocador 1 de Sódio-Hidrogênio/genética
9.
Sci Rep ; 11(1): 23470, 2021 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-34873242

RESUMO

Marine reserves are known to impact the biomass, biodiversity, and functions of coral reef fish communities, but the effect of protective management on fish traits is less explored. We used a time-series modelling approach to simultaneously evaluate the abundance, biomass, and traits of eight fish families over a chronosequence spanning 44 years of protection. We constructed a multivariate functional space based on six traits known to respond to management or disturbance and affect ecosystem processes: size, diet, position in the water column, gregariousness, reef association, and length at maturity. We show that biomass increased with a log-linear trend over the time-series, but abundance only increased after 20 years of closure, and with more variation among reserves. This difference is attributed to recovery rates being dependent on body sizes. Abundance-weighted traits and the associated multivariate space of the community change is driven by increased proportions over time of the trait categories: 7-15 cm body size; planktivorous; species low in the water column; medium-large schools; and species with high levels of reef association. These findings suggest that the trait compositions emerging after the cessation of fishing are novel and dynamic.


Assuntos
Peixes/crescimento & desenvolvimento , Peixes/fisiologia , Animais , Biodiversidade , Biomassa , Tamanho Corporal/fisiologia , Conservação dos Recursos Naturais/métodos , Recifes de Corais , Ecossistema , Fenótipo
10.
Braz. J. Biol. ; 81(4): 962-968, Oct.-Dec. 2021. tab, graf
Artigo em Inglês | VETINDEX, VETINDEX | ID: vti-762606

RESUMO

The tambaqui (Colossoma macropomum) is a fish of primary importance in South American aquaculture, principally in the Amazon region and has a particularly unique diet in the wild. Oryza spp, or Wild rice as it is commonly known, is native to the floodplains of muddy rivers in the Amazon region. The aim of this study was to analyze the physical performance and the effects of dietary levels of Oryza spp. via the hematological parameters, total food intake, conversion efficiency, growth ratio and swimming performance of this fish. Diets containing 45% Oryza spp. induced the best performance in tambaqui. Diets containing 15% and 30% did not affect these indices, thus indicating that this amount of Oryza can be used as an alternative energy source for this important species within Brazilian aquaculture.(AU)


O tambaqui Colossoma macropomum é um peixe de importância na aquicultura brasileira, especialmente na região amazônica. O arroz silvestre é comum nas planícies inundadas dos rios de aguas barrentas da Amazônia. O objetivo deste trabalho foi analisar os efeitos combinados do treinamento físico e dos níveis dietéticos de Oryza spp. nos parâmetros hematológicos, consumo de alimentos, eficiência de conversão, taxa de crescimento e desempenho de natação deste peixe. Dietas contendo 45% de arroz apresentaram o melhor desempenho para tambaquis. As dietas contendo 15% e 30% não afetaram esses índices, indicando que alguma quantidade de arroz pode ser usada como fonte de energia alternativa para esta importante espécie dentro da aquicultura.(AU)


Assuntos
Animais , Peixes/crescimento & desenvolvimento , Peixes/sangue , Oryza , Dieta/veterinária , Aquicultura
11.
Int J Mol Sci ; 22(22)2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34830486

RESUMO

Spermatogenesis is a process of self-renewal and differentiation in spermatogonial stem cells. During this process, germ cells and somatic cells interact intricately to ensure long-term fertility and accurate genome propagation. Spermatogenesis has been intensely investigated in mammals but remains poorly understood with regard to teleosts. Here, we performed single-cell RNA sequencing of ~9500 testicular cells from the male, orange-spotted grouper. In the adult testis, we divided the cells into nine clusters and defined ten cell types, as compared with human testis data, including cell populations with characteristics of male germ cells and somatic cells, each of which expressed specific marker genes. We also identified and profiled the expression patterns of four marker genes (calr, eef1a, s100a1, vasa) in both the ovary and adult testis. Our data provide a blueprint of male germ cells and supporting somatic cells. Moreover, the cell markers are candidates that could be used for further cell identification.


Assuntos
Peixes/genética , Organismos Hermafroditas/genética , Espermatogênese/genética , Testículo/crescimento & desenvolvimento , Animais , Proteínas de Peixes/genética , Peixes/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento/genética , Células Germinativas/metabolismo , Organismos Hermafroditas/crescimento & desenvolvimento , Masculino , RNA-Seq , Diferenciação Sexual/genética , Análise de Célula Única , Testículo/patologia
12.
PLoS One ; 16(11): e0260192, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34793569

RESUMO

In this study, we determined the effects of dietary chitosan on the growth, biochemical composition, gut microbiota, and hematological and histological parameters of juvenile Barbonymus gonionotus. Three test diets containing three different concentrations (1, 2, and 3 g kg-1 feed) of dietary chitosan were formulated. A basal diet without dietary chitosan was considered a control, and the fish were reared for 60 days. Comparing the effects of the dietary chitosan-containing diets with those of the control diet, we found that dietary chitosan significantly improved the muscle growth, nutrient and mineral contents, hematological parameters, lactic acid bacterium abundance, and digestive enzyme activities of B. gonionotus. Moreover, dietary chitosan significantly inhibited the growth of pathogenic bacteria in fish. Interestingly, an increase in the dietary chitosan level significantly enhanced the protein contents of the muscles and inversely significantly decreased the lipid contents compared to those with the basal diet. Quantitative study revealed that dietary chitosan significantly enhanced the length of intestinal villi, and qualitative study showed that dietary chitosan considerably reduced the fat content in the liver and improved the morphology of the kidney compared to those with the basal diet. Taken together, our results suggest that the application of dietary chitosan at a dose of 1 g kg-1 feed produced the highest benefit to treated B. gonionotus, indicating its potential for safe use in aquaculture.


Assuntos
Quitosana/administração & dosagem , Peixes/crescimento & desenvolvimento , Peixes/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Intestinos/efeitos dos fármacos , Animais , Dieta , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Intestinos/metabolismo , Rim/efeitos dos fármacos , Rim/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Músculos/efeitos dos fármacos , Músculos/metabolismo , Nutrientes/administração & dosagem
13.
Emerg Microbes Infect ; 10(1): 2128-2140, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34702148

RESUMO

Vibrio vulnificus is a pathogen of public health concern that causes either primary septicemia after ingestion of raw shellfish or secondary septicemia after wound exposure to seawater. In consequence, shellfish and seawater are considered its main reservoirs. However, there is one aspect of its biology that is systematically overlooked: its association with fish in its natural environment. This association led in 1975 to the emergence of a zoonotic clade within phylogenetic lineage 2 following successive outbreaks of vibriosis in farmed eels. Although this clade is now worldwide distributed, no new zoonotic clades were subsequently reported. In this work, we have performed phylogenetic, genomic and functional studies to show that other zoonotic clades are in fact present in 4 of the 5 lineages of the species. Further, we associate these clades, most of them previously but incompletely described, with the acquisition of a family of fish virulence plasmids containing genes essential for resistance to the immune system of certain teleosts of interest in aquaculture. Consequently, our results provide several pieces of evidence about the importance of this species as a zoonotic agent linked to fish farms, as well as on the relevance of these artificial environments acting as drivers that accelerate the evolution of the species.


Assuntos
Zoonoses Bacterianas/microbiologia , Doenças dos Peixes/microbiologia , Plasmídeos/genética , Vibrioses/microbiologia , Vibrioses/veterinária , Vibrio vulnificus/genética , Vibrio vulnificus/patogenicidade , Animais , Aquicultura , Zoonoses Bacterianas/transmissão , Peixes/crescimento & desenvolvimento , Peixes/microbiologia , Humanos , Filogenia , Plasmídeos/metabolismo , Vibrioses/transmissão , Vibrio vulnificus/classificação , Vibrio vulnificus/metabolismo , Virulência
14.
J Therm Biol ; 100: 103063, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34503801

RESUMO

This article reports on the thermal tolerance, metabolic capacity and performance of juvenile meagre (Argyrosomus regius) reared under three high water temperatures (24, 29 and 34 °C) for three months. The analysis includes the thermal effects on the growth performance, metabolism and physiology of meagre, including a range of molecular, haematological, metabolic, enzymatic and hormonal indicators, as well as the effects on the proximate composition and ingestion speed. Meagre performs best between 24 and 29 °C while the temperature of 34 °C is very close to the upper end of its temperature tolerance range. At 34 °C meagre exhibits a poor growth performance and physiological status, increased blood clotting, high mortality rates and a diminished capacity for aerobic metabolism, as indicated by its low aerobic scope (129 mg kg-1 h-1). Meagre may tolerate short exposures to high temperatures after sufficient acclimation (Critical thermal maximum of 37.5 °C after acclimation to 29 °C) but its overall performance declines under prolonged exposure, suggesting that this emerging aquaculture species may be vulnerable to global warming. Our work corroborates previous findings on the thermal preferences of the species, identifies critical biological thresholds, and provides insights into the effects of prolonged exposure to high temperature regimes.


Assuntos
Peixes/fisiologia , Termotolerância , Animais , Metabolismo Basal , Coagulação Sanguínea , Peso Corporal , Respiração Celular , Pesqueiros , Peixes/crescimento & desenvolvimento , Peixes/metabolismo , Natação
15.
Nat Commun ; 12(1): 5413, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34526495

RESUMO

Numerous studies have focused on the need to expand production of 'blue foods', defined as aquatic foods captured or cultivated in marine and freshwater systems, to meet rising population- and income-driven demand. Here we analyze the roles of economic, demographic, and geographic factors and preferences in shaping blue food demand, using secondary data from FAO and The World Bank, parameters from published models, and case studies at national to sub-national scales. Our results show a weak cross-sectional relationship between per capita income and consumption globally when using an aggregate fish metric. Disaggregation by fish species group reveals distinct geographic patterns; for example, high consumption of freshwater fish in China and pelagic fish in Ghana and Peru where these fish are widely available, affordable, and traditionally eaten. We project a near doubling of global fish demand by mid-century assuming continued growth in aquaculture production and constant real prices for fish. Our study concludes that nutritional and environmental consequences of rising demand will depend on substitution among fish groups and other animal source foods in national diets.


Assuntos
Peixes/crescimento & desenvolvimento , Abastecimento de Alimentos/estatística & dados numéricos , Alimentos , Renda/estatística & dados numéricos , Alimentos Marinhos/estatística & dados numéricos , África , Animais , Aquicultura/métodos , Ásia , Europa (Continente) , Abastecimento de Alimentos/métodos , Água Doce , Geografia , Saúde Global , Humanos , Modelos Teóricos , América do Norte , Alimentos Marinhos/provisão & distribuição , América do Sul
16.
Biol Open ; 10(10)2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34590124

RESUMO

The morphogenesis of the vertebrate eye consists of a complex choreography of cell movements, tightly coupled to axial regionalization and cell type specification processes. Disturbances in these events can lead to developmental defects and blindness. Here, we have deciphered the sequence of defective events leading to coloboma in the embryonic eye of the blind cavefish of the species Astyanax mexicanus. Using comparative live imaging on targeted enhancer-trap Zic1:hsp70:GFP reporter lines of both the normal, river-dwelling morph and the cave morph of the species, we identified defects in migratory cell behaviours during evagination that participate in the reduced optic vesicle size in cavefish, without proliferation defect. Further, impaired optic cup invagination shifts the relative position of the lens and contributes to coloboma in cavefish. Based on these results, we propose a developmental scenario to explain the cavefish phenotype and discuss developmental constraints to morphological evolution. The cavefish eye appears as an outstanding natural mutant model to study molecular and cellular processes involved in optic region morphogenesis.


Assuntos
Cegueira/genética , Olho/crescimento & desenvolvimento , Peixes/crescimento & desenvolvimento , Morfogênese/genética , Animais , Evolução Molecular
17.
Artigo em Inglês | MEDLINE | ID: mdl-34478847

RESUMO

This study aimed to investigate the effects of replacing fish meal (FM) with soybean protein concentrates (SPC) on the intermediary metabolism and health of Totoaba macdonaldi juveniles. Fish (initial weight 50 ± 1 g) were fed for 60 days with eight diets: a reference diet (RD) and seven experimental diets where FM was replaced gradually with 15 to 100% SPC (SPC15, SPC30, SPC45, SPC60, SPC75, SPC90, and SPC100, respectively). Hexokinase (HK), glucokinase (GK), and alanine aminotransferase (ALT) enzyme activities showed highly significant differences (p < 0.01) between fish fed RD (0% SPC) compared to fish fed the diets with 60, 75, 90, and 100% SPC. The ALT enzyme shows a highly significant (p < 0.01) decrease in activity for fish fed 75, 90, and 100% SPC inclusions compared to fish fed the RD. The aspartate aminotransferase AST/ALT ratio showed a significant increase in activity for fish fed 100% soybean compared only with fish fed the control diet. The histological organization of the liver in totoaba juveniles fed RD, SPC15, SPC30 and SPC45 diets were similar. Totoaba fed with SPC90 and SPC100 showed histological alterations in hepatic and pancreatic parenchyma. Overall, according to the findings in this study, 45% of dietary FM could be replaced by SPC without causing adverse changes in metabolism, histological organization of liver, and health of juveniles of totoaba when cultured for 60 days. However, levels greater than 60% of SPC could compromise the health status of fish.


Assuntos
Metabolismo Energético , Peixes/metabolismo , Fígado/metabolismo , Valor Nutritivo , Proteínas de Soja/administração & dosagem , Alanina Transaminase/metabolismo , Ração Animal , Animais , Aspartato Aminotransferases/metabolismo , Proteínas de Peixes/metabolismo , Peixes/crescimento & desenvolvimento , Glucoquinase/metabolismo , Hexoquinase/metabolismo , Fígado/patologia , Pâncreas/patologia , Proteínas de Soja/metabolismo , Proteínas de Soja/toxicidade , Fatores de Tempo , Ganho de Peso
18.
Braz. J. Biol. ; 81(3): 765-775, July-Sept. 2021. mapas, tab, graf
Artigo em Inglês | VETINDEX, VETINDEX | ID: vti-762658

RESUMO

In aquatic environments, dams are considered one of the main threats to fish species, acting as an environmental filter for certain functional traits. Although there is some predictability in the composition of the functional traits in reservoirs, it is hypothesized that the environmental filters imposed by evolutionary processes, linked to the characteristics of the basins, are determinant for the functional composition of the traits in reservoirs. For this we performed a PCoA using the functional traits composition matrix of the reservoirs. We used PERMANOVA to test the difference in functional composition between basins. We performed the same process for the species composition matrix to compare the patterns. In this study, there were taxonomic and functional differences among reservoirs inserted in different basins. It was observed that the basin is a determining factor for the functional structure of fish assemblage in reservoirs. When compared, functional and taxonomic structures follow the same pattern, although functionally the reservoir tends to be more similar. These results reinforce the idea that reservoirs act as filters for functional traits (e.g., related with reproduction, feeding and habitat use), although there is a great influence of evolutionary processes related to the basins characteristics and origin of the ichthyofaunistic province.(AU)


Em ambientes aquáticos, a construção de barragens é considerada uma das principais ameaças para as espécies de peixes, atuando como filtro ambiental para determinados traços funcionais. Assim, embora exista certa previsibilidade na composição dos traços funcionais em reservatórios, é hipotetizado que os filtros ambientais impostos pelos processos evolutivos, ligados as características das bacias, são determinantes para a composição funcional dos traços nos reservatórios. Para isso realizamos uma PCoA utilizando a matriz de composição de traços funcionais dos reservatórios. Utilizamos a PERMANOVA para testar a diferença da composição funcional entre as bacias. Realizamos o mesmo processo para a matriz de composição de espécies para comparar os padrões. Foi possível observar que a bacia hidrográfica é um fator determinante para a estruturação funcional da assembleia de peixe em reservatórios. Quando comparadas, a estrutura funcional e taxonômica, ambas seguem o mesmo padrão, embora funcionalmente os ambientes tendem a ser mais semelhantes. Esses resultados reforçam a ideia de que reservatórios atuam como filtros para determinados traços funcionais (e.g., relacionados à reprodução, alimentação e uso de habitat), embora exista uma grande influência dos processos evolutivos ligados a característica da bacia e da origem da província ictiofaunística.(AU)


Assuntos
Animais , Peixes/crescimento & desenvolvimento , Bacias Hidrográficas/efeitos adversos , Barragens/efeitos adversos , Zona Tropical
19.
PLoS One ; 16(8): e0255879, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34403437

RESUMO

Taking advantage of published data on life-history traits and short-term information on fishery parameters from 3132 records for 644 fish stocks along the coast of India, we calculated resilience (R) and vulnerability (V). Further, we developed an Index of Resilience and Vulnerability (IRV) for 133 species of tropical finfishes, crustaceans, and molluscs. Using 7 resilience and 6 vulnerability attributes, two-dimensional scatter plots of the resilience and vulnerability scores were generated and the Euclidean distance and angle from the origin to each point were calculated to determine IRV and the effect of fishing on fish species. By ranking the species, the top 10 highly resilient, highly vulnerable, and high-risk species (low IRV) were identified. While small-sized species with fast growth rate and low trophic level were among the highly resilient species, large predatory species such as sharks and barracudas were among the highly vulnerable and high-risk species. More than 100 of the 133 species were resilient-yet-vulnerable, and most crustaceans showed high resilience. Differences in IRV scores among species within the same family were discernible, indicating the differences in the biological characteristics and response to fishing. Sensitivity analysis indicated that an abridged IRV with 6 attributes works similar to 13 attributes and can be used in data-deficient situations. Comparison of R and V of IRV with other assessments showed different results because of divergences in the objectives, number and types of attributes, and thresholds used. These assessments do not convey the same information and therefore great care must be taken for reproducing these frameworks to other fisheries. The results of IRV analysis can be useful for stock assessments and in developing effective management measures in combination with other complementary information.


Assuntos
Pesqueiros , Peixes/fisiologia , Animais , Conservação dos Recursos Naturais , Ecossistema , Peixes/crescimento & desenvolvimento , Índia , Longevidade , Moluscos/fisiologia , Reprodução/fisiologia
20.
Artigo em Inglês | MEDLINE | ID: mdl-34411697

RESUMO

Tropical gar (Atractosteus tropicus) thrives in aquatic habitats with high levels of total nitrogen (TAN) and unionized ammonia (NH3). However, the tolerance of TAN and NH3, the excretion mechanisms involved, and the effects of these chemicals on routine metabolism are still unknown. Therefore, our objectives were to assess the acute toxicity of TAN and NH3 in A. tropicus juveniles after a 96-h exposure (LC50-96 h) to NH4Cl and after chronic exposure to two concentrations (15% and 30% of LC50-96 h TAN) for 12 days, as well as to evaluate the transcriptional effects associated with Rhesus proteins (rhag, rhbg, rhcg) and ion transporters (NHE, NKA, NKCC, and CFTR) in gills and skin; and to determine the effects of TAN and NH3 on routine metabolism through oxygen consumption (µM g-1 h-1) and gill ventilation frequency (beats min-1). LC50-96 h values were 100.20 ± 11.21 mg/L for TAN and 3.756 ± 0.259 mg/L for NH3. The genes encoding Rhesus proteins and ion transporters in gills and skin showed a differential expression according to TAN concentrations and exposure time. Oxygen consumption on day 12 showed significant differences between treatments with 15% and 30% TAN. Gill ventilation frequency on day 12 was higher in fish exposed to 30% TAN. In conclusion, A. tropicus juveniles are highly tolerant to TAN, showing upregulation of the genes involved in TAN excretion through gills and skin, which affects routine oxygen consumption and energetic cost. These findings are relevant for understanding adaptations in the physiological response of a tropical ancestral air-breathing fish.


Assuntos
Amônia/toxicidade , Proteínas de Transporte/metabolismo , Proteínas de Peixes/metabolismo , Peixes/metabolismo , Nitrogênio/toxicidade , Animais , Proteínas de Transporte/genética , Proteínas de Peixes/genética , Peixes/crescimento & desenvolvimento , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Brânquias/patologia , Transporte de Íons , Larva , Pele/efeitos dos fármacos , Pele/metabolismo , Pele/patologia , Poluentes Químicos da Água/toxicidade
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