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1.
J Invertebr Pathol ; 202: 108039, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38097037

RESUMO

The microbiome influences a variety of host-environment interactions, and there is mounting evidence of its significant role in biological invasions. During invasion, shifts in microbial diversity and function can occur due to both changing characteristics of the novel environment and physiological condition of the host. The signal crayfish (Pacifastacus leniusculus) is one of the most successful crayfish invaders in Europe. During range expansion, its populations often exhibit differences in many traits along the invasion range, including sex-composition, size-structure and aggressiveness, but to date it was not studied whether crayfish traits can also drive changes in the host microbiome. Thus, we used 16S rRNA gene amplicon sequencing to examine the effects of host-related traits, namely total length (TL), body condition index (FCF), hepatosomatic index (HSI) and sex on the microbial diversity of the signal crayfish. We examined both external (exoskeletal) and internal (intestinal, hepatopancreatic, hemolymph) microbiomes of 110 signal crayfish individuals from four sites along its invasion range in the Korana River, Croatia. While sex did not exhibit a significant effect on the microbial diversity in any of the examined tissues, exoskeletal, intestinal and hemolymph microbial diversity significantly decreased with increasing crayfish size. Additionally, significant effects of signal crayfish condition (FCF, HSI) on microbial diversity were recorded in the hepatopancreas, a main energy storage organ in crayfish that supports reproduction and growth and also regulates immune response. Our findings provide a baseline for evaluating the contribution of microbiome to an invader's overall health, fitness and subsequent invasion success.


Assuntos
Astacoidea , Humanos , Animais , RNA Ribossômico 16S/genética , Europa (Continente) , Croácia
2.
FEMS Microbes ; 4: xtad011, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37389204

RESUMO

The activity of the microbiome of fish mucosae provides functions related to immune response, digestion, or metabolism. Several biotic and abiotic factors help maintaining microbial homeostasis, with disruptions leading to dysbiosis. Diseases and antibiotic administration are known to cause dysbiosis in farmed fish. Pathogen infections greatly affect the production of gilthead seabream, and antibiotic treatment is still frequently required. Here, we employed a 16S rRNA high-throughput metataxonomics approach to characterize changes in the gut, skin, and gill microbiomes occurring due to infection with Photobacterium damselae subsp. piscicida and subsequent antibiotic treatment with oxytetracycline (OTC), as well as during recovery. Although microbiota response differed between studied tissues, overall changes in composition, diversity, structure, and predicted function were observed in all mucosae. The skin and gill microbiomes of diseased fish became largely dominated by taxa that have been frequently linked to secondary infections, whereas in the gut the genus Vibrio, known to include pathogenic bacteria, increased with OTC treatment. The study highlights the negative impacts of disease and antibiotic treatment on the microbiome of farmed fish. Our results also suggest that fish transportation operations may have profound effects on the fish microbiome, but further studies are needed to accurately evaluate their impact.

3.
Microb Ecol ; 83(3): 789-797, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34245329

RESUMO

The microbiota of fish skin, the primary barrier against disease, is highly dynamic and modulated by several factors. In fish aquaculture, disease outbreaks occur mainly during early-life stages, with associated high economic losses. Antibiotic treatments sometimes remain the best option to control bacterial diseases, despite many reported negative impacts of its use on fish and associated microbiota. Notwithstanding, studies monitoring the effects of disease and antibiotic treatment on the microbiota of fingerlings are scarce. We sequenced the bacterial 16S rRNA V4 gene region using a metabarcoding approach to assess the impact of a mixed infection with Photobacterium damselae ssp. piscicida and Vibrio harveyi and subsequent antibiotic treatment with flumequine, on the skin microbiota of farmed seabass (Dicentrarchus labrax) fingerlings. Both infection and antibiotic treatment led to a significant increase in bacterial diversity and core microbial communities and impacted microbiome structure. Dysbiosis was confirmed by changes in the abundance of potential pathogenic and opportunistic bacterial taxa. Skin bacterial metabolic function was also significantly affected by flumequine administration, suggesting a detriment to fish skin health. Our results add to an increasing body of literature, showing how fish microbiome response to infection and antibiotics cannot be easily predicted.


Assuntos
Bass , Doenças dos Peixes , Microbiota , Animais , Antibacterianos/farmacologia , Aquicultura/métodos , Bass/genética , Bass/microbiologia , Doenças dos Peixes/tratamento farmacológico , Doenças dos Peixes/microbiologia , Photobacterium/genética , RNA Ribossômico 16S/genética
4.
Anim Microbiome ; 3(1): 10, 2021 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-33499971

RESUMO

BACKGROUND: Important changes in microbial composition related to sexual maturation have been already reported in the gut of several vertebrates including mammals, amphibians and fish. Such changes in fish are linked to reproduction and growth during developmental stages, diet transitions and critical life events. We used amplicon (16S rRNA) high-throughput sequencing to characterize the skin and gill bacterial microbiota of farmed seabass and seabream belonging to three different developmental age groups: early and late juveniles and mature adults. We also assessed the impact of the surrounding estuarine water microbiota in shaping the fish skin and gill microbiota. RESULTS: Microbial diversity, composition and predicted metabolic functions varied across fish maturity stages. Alpha-diversity in the seabass microbiota varied significantly between age groups and was higher in older fish. Conversely, in the seabream, no significant differences were found in alpha-diversity between age groups. Microbial structure varied significantly across age groups; moreover, high structural variation was also observed within groups. Different bacterial metabolic pathways were predicted to be enriched in the microbiota of both species. Finally, we found that the water microbiota was significantly distinct from the fish microbiota across all the studied age groups, although a high percentage of ASVs was shared with the skin and gill microbiotas. CONCLUSIONS: We report important microbial differences in composition and potential functionality across different ages of farmed seabass and seabream. These differences may be related to somatic growth and the onset of sexual maturation. Importantly, some of the inferred metabolic pathways could enhance the fish coping mechanisms during stressful conditions. Our results provide new evidence suggesting that growth and sexual maturation have an important role in shaping the microbiota of the fish external mucosae and highlight the importance of considering different life stages in microbiota studies.

5.
Microorganisms ; 10(1)2021 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-35056514

RESUMO

Vermicomposting is the process of organic waste degradation through interactions between earthworms and microbes. A variety of organic wastes can be vermicomposted, producing a nutrient-rich final product that can be used as a soil biofertilizer. Giving the prolific invasive nature of the Australian silver wattle Acacia dealbata Link in Europe, it is important to find alternatives for its sustainable use. However, optimization of vermicomposting needs further comprehension of the fundamental microbial processes. Here, we characterized bacterial succession during the vermicomposting of silver wattle during 56 days using the earthworm species Eisenia andrei. We observed significant differences in α- and ß-diversity between fresh silver wattle (day 0) and days 14 and 28, while the bacterial community seemed more stable between days 28 and 56. Accordingly, during the first 28 days, a higher number of taxa experienced significant changes in relative abundance. A microbiome core composed of 10 amplicon sequence variants was identified during the vermicomposting of silver wattle (days 14 to 56). Finally, predicted functional profiles of genes involved in cellulose metabolism, nitrification, and salicylic acid also changed significantly during vermicomposting. This study, hence, provides detailed insights of the bacterial succession occurring during vermicomposting of the silver wattle and the characteristics of its final product as a sustainable plant biofertilizer.

6.
ISME Commun ; 1(1): 28, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-36739461

RESUMO

Fish microbiota are intrinsically linked to health and fitness, but they are highly variable and influenced by both biotic and abiotic factors. Water temperature particularly limits bacterial adhesion and growth, impacting microbial diversity and bacterial infections on the skin and gills. Aquaculture is heavily affected by infectious diseases, especially in warmer months, and industry practices often promote stress and microbial dysbiosis, leading to an increased abundance of potentially pathogenic bacteria. In this regard, fish mucosa health is extremely important because it provides a primary barrier against pathogens. We used 16 rRNA V4 metataxonomics to characterize the skin and gill microbiota of the European seabass, Dicentrarchus labrax, and the surrounding water over 12 months, assessing the impact of water temperature on microbial diversity and function. We show that the microbiota of external mucosae are highly dynamic with consistent longitudinal trends in taxon diversity. Several potentially pathogenic genera (Aliivibrio, Photobacterium, Pseudomonas, and Vibrio) were highly abundant, showing complex interactions with other bacterial genera, some of which with recognized probiotic activity, and were also significantly impacted by changes in temperature. The surrounding water temperature influenced fish microbial composition, structure and function over time (days and months). Additionally, dysbiosis was more frequent in warmer months and during transitions between cold/warm months. We also detected a strong seasonal effect in the fish microbiota, which is likely to result from the compound action of several unmeasured environmental factors (e.g., pH, nutrient availability) beyond temperature. Our results highlight the importance of performing longitudinal studies to assess the impact of environmental factors on fish microbiotas.

7.
Sci Rep ; 9(1): 18946, 2019 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-31831775

RESUMO

The mucosal surfaces of fish harbour microbial communities that can act as the first-line of defense against pathogens. Infectious diseases are one of the main constraints to aquaculture growth leading to huge economic losses. Despite their negative impacts on microbial diversity and overall fish health, antibiotics are still the method of choice to treat many such diseases. Here, we use 16 rRNA V4 metataxonomics to study over a 6 week period the dynamics of the gill and skin microbiomes of farmed seabass before, during and after a natural disease outbreak and subsequent antibiotic treatment with oxytetracycline. Photobacterium damselae was identified as the most probable causative agent of disease. Both infection and antibiotic treatment caused significant, although asymmetrical, changes in the microbiome composition of the gills and skin. The most dramatic changes in microbial taxonomic abundance occurred between healthy and diseased fish. Disease led to a decrease in the bacterial core diversity in the skin, whereas in the gills there was both an increase and a shift in core diversity. Oxytetracycline caused a decrease in core diversity in the gill and an increase in the skin. Severe loss of core diversity in fish mucosae demonstrates the disruptive impact of disease and antibiotic treatment on the microbial communities of healthy fish.


Assuntos
Antibacterianos/farmacologia , Bass/microbiologia , Surtos de Doenças , Doenças dos Peixes , Infecções por Bactérias Gram-Negativas , Microbiota/efeitos dos fármacos , Oxitetraciclina/farmacologia , Photobacterium/metabolismo , Animais , Aquicultura , Doenças dos Peixes/tratamento farmacológico , Doenças dos Peixes/epidemiologia , Doenças dos Peixes/microbiologia , Brânquias/microbiologia , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/epidemiologia , Infecções por Bactérias Gram-Negativas/veterinária , Pele/microbiologia
8.
Front Microbiol ; 10: 716, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31024495

RESUMO

The broadstripe cleaning goby Elacatinus prochilos has two alternative ecotypes: sponge-dwellers, which live in large groups and feed mainly upon nematode parasites; and coral-dwellers, that live in small groups or in solitude and behave as cleaners. Recent studies focusing on the skin and gut microbiomes of tropical fish showed that microbial communities are influenced mainly by diet and host species. Here, we compare the skin and gut microbiomes of the Caribbean broadstripe cleaning goby E. prochilos alternative ecotypes (cleaners and non-cleaners) from Barbados and predict that different habitat use and behavior (cleaning vs. non-cleaning) will translate in different bacterial profiles between the two ecotypes. We found significant differences in both alpha- and beta-diversity of skin and gut microbiomes belonging to different ecotypes. Importantly, the skin microbiome of obligate cleaners showed greater intra-sample diversity and harbored a significantly higher prevalence of potential fish pathogens. Likewise, potential pathogens were also more prevalent in the gut of obligate cleaners. We suggest that habitat use, diet, but also direct contact with potential diseased clientele during cleaning, could be the cause for these patterns.

9.
J. Phys. Educ. (Maringá) ; 30: e3067, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1286905

RESUMO

ABSTRACT This study aimed at carrying out a systematic review on violence with regard to vocational training in the fields of Education and Physical Education (PE) from 2000 to 2017. The following descriptors were used: formação profissional e violência , violência e docente; vocational training and violence, teacher training and violence, formación professional y violencia, formación del profesorado y violencia. After the methodological procedures, 25 articles were selected for analysis. Considering the fields mentioned, the results showed the shortage of productions on the subject. The social responsibility of educational institutions is emphasized in the sense of addressing the subject, whether regarding vocational training and/or continuing education.


RESUMO O objetivo desse trabalho foi realizar uma revisão sistemática sobre o tema violência no contexto da formação profissional nas áreas da Educação e da Educação Física (EF) no período entre 2000 e 2017. Para a busca, foram utilizados os seguintes descritores: formação profissional e violência, violência e docente, professional formation and violence, professional training and violence, vocational training and violence, violência e formação de professores, violence and teacher training e violencia and formación del profesorado. Após os procedimentos metodológicos, restaram 25 artigos para análise. Os resultados revelam a escassez de produções sobre o assunto nas áreas mencionadas. Enfatiza-se a responsabilidade social das instituições de ensino em abordarem o assunto, seja na formação profissional e/ou na formação continuada.


Assuntos
Capacitação de Professores , Violência de Gênero , Educação Física e Treinamento , Violência , Educação , Educação Continuada , Professores Escolares
10.
Licere (Online) ; 21(3): 57-89, set.2018. tab, graf
Artigo em Português | LILACS | ID: biblio-946409

RESUMO

Este estudo objetivou quantificar e analisar a produção científica sobre lazer de universitários entre os anos 2001-2016 nas bases de dados Scielo, BVS, Periódicos Capes e SportDiscus utilizando os descritores: lazer, universitário e o conector and. Os critérios de inclusão foram: artigos produzidos no século XXI, publicados em inglês, português ou espanhol. A análise dos dados foi feita com base em 13 categorias preestabelecidas. Catorze estudos foram selecionados, a maioria produzida nos últimos três anos; tiveram autoria coletiva; autores vinculados a Universidades Públicas; predominantemente em São Paulo; predominantemente ligados à área Psicologia; utilizam questionários adaptados com questões abertas e fechadas; são abordagens de estudo voltadas ao tipo de atividades desenvolvidas por estudantes nos momentos de lazer; e o maior número de publicações ocorreu na revista Licere.


The objective of this study was to quantify and analyze the scientific production on leisure of university students between 2001 and 2016 in the databases Scielo, BVS, Capes Periods and SportDiscus using the descriptors: leisure and university. The inclusion criteria were: produced in the 21st century, published in English, Portuguese or Spanish. Data analysis was based on 13 pre-established categories. Fourteen studies were selected, most were produced in the last three years; they had collective authorship; authors linked to Public Universities; predominantly in São Paulo; predominantly linked to the Psychology area; use questionnaires adapted with open and closed questions; the study approaches aimed at the type of activities developed by students in leisure time; and the largest number of publications occurred in Licere magazine.


Assuntos
Humanos , Recreação , Descanso , Estudantes , Domínios Científicos , Atividades Científicas e Tecnológicas , Atividades de Lazer
11.
Parasit Vectors ; 11(1): 63, 2018 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-29370873

RESUMO

BACKGROUND: The Apicomplexa from aquatic environments are understudied relative to their terrestrial counterparts, and the seminal work assessing the phylogenetic relations of fish-infecting lineages is mostly based on freshwater hosts. The taxonomic uncertainty of some apicomplexan groups, such as the coccidia, is high and many genera were recently shown to be paraphyletic, questioning the value of strict morphological and ecological traits for parasite classification. Here, we surveyed the genetic diversity of the Apicomplexa in several commercially valuable vertebrates from the North-East Atlantic, including farmed fish. RESULTS: Most of the sequences retrieved were closely related to common fish coccidia of Eimeria, Goussia and Calyptospora. However, some lineages from the shark Scyliorhinus canicula were placed as sister taxa to the Isospora, Caryospora and Schellakia group. Additionally, others from Pagrus caeruleostictus and Solea senegalensis belonged to an unknown apicomplexan group previously found in the Caribbean Sea, where it was sequenced from the water column, corals, and fish. Four distinct parasite lineages were found infecting farmed Dicentrarchus labrax or Sparus aurata. One of the lineages from farmed D. labrax was also found infecting wild counterparts, and another was also recovered from farmed S. aurata and farm-associated Diplodus sargus. CONCLUSIONS: Our results show that marine fish apicomplexans are diverse, and we highlight the need for a more extensive assessment of parasite diversity in this phylum. Additionally, parasites recovered from S. canicula were recovered as basal to their piscine counterparts reflecting hosts phylogeny.


Assuntos
Apicomplexa/classificação , Apicomplexa/isolamento & purificação , Organismos Aquáticos/classificação , Organismos Aquáticos/isolamento & purificação , Biodiversidade , Doenças dos Peixes/parasitologia , Infecções Protozoárias em Animais/parasitologia , Animais , Apicomplexa/genética , Organismos Aquáticos/genética , Oceano Atlântico , Peixes , Variação Genética
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