Effects of leaf quality and colonization time on the abundance of bacteria in an experimental design

Small rivers, henceforth streams, depend on organic matter (nutrients and energy) from riparian vegetation. The quality of such allochthonous debris is determinant for the transformation of organic matter compounds, where the bacterial community has a crucial role in the final decomposition of the substrate. During bacterial colonization, debris with higher concentration of nutrients (more palatable) is prioritized, which accelerates the process. This study investigated the effects of leaf palatability of two native trees on bacterial colonization (abundance) over time, through a laboratory experiment that lasted 60 days. Values of C, N, P, C:N, C:P, polyphenols, tannins, lignin, lignin:N and leaf toughness of both species were compared. Bacterial abundance was higher in species with higher nitrogen values, although they had higher leaf toughness and more polyphenols, which differs from studies indicating that high leaf toughness represents low nutritional quality. The colonization time did not influence bacterial abundance. Therefore, processes degrading riparian vegetation and reducing nutritional quality can affect local decomposition, decreasing bacterial abundance.(AU)

Characterization of Enterococcus spp. isolated from a fish farming environment in southern Brazil / Caracterização de Enterococcus spp. isolado de um ambiente de piscicultura no sul do Brasil

The aim of present study is to characterize the resistance and virulence profile of enterococci isolated from aquaculture excavated ponds and masonry tanks (6 samples) in southern Brazil. Samples were cultured in selective medium, 10 colonies were randomly selected from each sample, which were identified by MALDI-TOF and tested against 13 antimicrobials. The presence of resistance (tetL, tetM, tetS, ermB and msrC) and virulence (ace, esp, agg, cylA and gelE) genes were determined by PCR. A total of 79 enterococci were identified, and Entecococcus faecalis (44.3%) and E. casseliflavus (36.7%) were the most prevalent species isolated. Sixty-five strains (82.3%) were resistant to at least one of the antimicrobials tested, whereas 27 (34.2%) strains were multiresistant. The overall percentages of antimicrobial resistant isolates were: 58.2% to rifampicin, 40.5% to fluoroquinolones, 36.7% to erythromycin and 30.4% to tetracycline. The tetL and tetM genes were found in 57.7% of the tetracycline-resistant strains; and msrC in 31.01% of erythromycin-resistant strains. The most frequently detected virulence factors were ace and gelE genes. Although limited to a single farm, these data suggest that aquaculture may be a reservoir of resistant and virulent enterococci. This study is the first step towards enhancing our understandingof distribution, resistance and virulence profile in enterococci isolated from fish farming environments in the south Brazil.(AU)

O objetivo do estudo apresentado é caracterizar o perfil de resistência e virulência de enterococos isolados de viveiros escavados e tanques de alvenaria (6 amostras) de uma pisicultura no Sul do Brasil. As amostras foram cultivadas em meio seletivo, 10 colônias foram selecionadas aleatoriamente de cada amostra, que foram identificadas por MALDI-TOF e testadas contra 13 antimicrobianos. A presença de genes de resistência (tetL, tetM, tetS, ermB e msrC) e virulência (ace, esp, agg, cylA e gelE) foi determinada por PCR. Foram identificados 79 enterococos, sendo Entecococcus faecalis (44,3%) e E. casseliflavus (36,7%) as espécies mais frequentes isoladas. Sessenta e cinco cepas (82,3%) eram resistentes a pelo menos um dos antimicrobianos testados, enquanto 27 (34,2%) eram multirresistentes. As porcentagens gerais de isolados resistentes a antimicrobianos foram: 58,2% para rifampicina, 40,5% para fluoroquinolonas, 36,7% para eritromicina e 30,4% para tetraciclina. Os genes tetL e tetM foram encontrados em 57,7% das cepas resistentes à tetraciclina; e msrC em 31,01% das cepas resistentes à eritromicina. Os fatores de virulência mais comumente detectados foram ace e gelE. Embora limitados a uma única fazenda, esses dados indicam que a aquicultura pode ser uma fonte de enterococos resistentes e virulentos. Este estudo é o primeiro passo para melhorar nosso entendimento da distribuição, resistência e perfil de virulência em enterococos isolados de ambientes de piscicultura no sul do Brasil.(AU)

Characterization of Enterococcus spp. isolated from a fish farming environment in southern Brazil

Abstract The aim of present study is to characterize the resistance and virulence profile of enterococci isolated from aquaculture excavated ponds and masonry tanks (6 samples) in southern Brazil. Samples were cultured in selective medium, 10 colonies were randomly selected from each sample, which were identified by MALDI-TOF and tested against 13 antimicrobials. The presence of resistance (tetL, tetM, tetS, ermB and msrC) and virulence (ace, esp, agg, cylA and gelE) genes were determined by PCR. A total of 79 enterococci were identified, and Entecococcus faecalis (44.3%) and E. casseliflavus (36.7%) were the most prevalent species isolated. Sixty-five strains (82.3%) were resistant to at least one of the antimicrobials tested, whereas 27 (34.2%) strains were multiresistant. The overall percentages of antimicrobial resistant isolates were: 58.2% to rifampicin, 40.5% to fluoroquinolones, 36.7% to erythromycin and 30.4% to tetracycline. The tetL and tetM genes were found in 57.7% of the tetracycline-resistant strains; and msrC in 31.01% of erythromycin-resistant strains. The most frequently detected virulence factors were ace and gelE genes. Although limited to a single farm, these data suggest that aquaculture may be a reservoir of resistant and virulent enterococci. This study is the first step towards enhancing our understandingof distribution, resistance and virulence profile in enterococci isolated from fish farming environments in the south Brazil.

Resumo O objetivo do estudo apresentado é caracterizar o perfil de resistência e virulência de enterococos isolados de viveiros escavados e tanques de alvenaria (6 amostras) de uma pisicultura no Sul do Brasil. As amostras foram cultivadas em meio seletivo, 10 colônias foram selecionadas aleatoriamente de cada amostra, que foram identificadas por MALDI-TOF e testadas contra 13 antimicrobianos. A presença de genes de resistência (tetL, tetM, tetS, ermB e msrC) e virulência (ace, esp, agg, cylA e gelE) foi determinada por PCR. Foram identificados 79 enterococos, sendo Entecococcus faecalis (44,3%) e E. casseliflavus (36,7%) as espécies mais frequentes isoladas. Sessenta e cinco cepas (82,3%) eram resistentes a pelo menos um dos antimicrobianos testados, enquanto 27 (34,2%) eram multirresistentes. As porcentagens gerais de isolados resistentes a antimicrobianos foram: 58,2% para rifampicina, 40,5% para fluoroquinolonas, 36,7% para eritromicina e 30,4% para tetraciclina. Os genes tetL e tetM foram encontrados em 57,7% das cepas resistentes à tetraciclina; e msrC em 31,01% das cepas resistentes à eritromicina. Os fatores de virulência mais comumente detectados foram ace e gelE. Embora limitados a uma única fazenda, esses dados indicam que a aquicultura pode ser uma fonte de enterococos resistentes e virulentos. Este estudo é o primeiro passo para melhorar nosso entendimento da distribuição, resistência e perfil de virulência em enterococos isolados de ambientes de piscicultura no sul do Brasil.

Cultivated bacterial diversity associated with the carnivorous plant Utricularia breviscapa (Lentibulariaceae) from floodplains in Brazil

Carnivorous plant species, such as Utricularia spp., capture and digest prey. This digestion can occur through the secretion of plant digestive enzymes and/or by bacterial digestive enzymes. To comprehend the physiological mechanisms of carnivorous plants, it is essential to understand the microbial diversity related to these plants. Therefore, in the present study, we isolated and classified bacteria from different organs of Utricularia breviscapa (stolons and utricles) and from different geographic locations (São Paulo and Mato Grosso). We were able to build the first bacterium collection for U. breviscapa and study the diversity of cultivable bacteria. The results show that U. breviscapa bacterial diversity varied according to the geographic isolation site (São Paulo and Mato Grosso) but not the analyzed organs (utricle and stolon). We reported that six genera were common to both sample sites (São Paulo and Mato Grosso). These genera have previously been reported to be beneficial to plants, as well as related to the bioremediation process, showing that these isolates present great biotechnological and agricultural potential. This is the first report of an Acidobacteria isolated from U. breviscapa. The role of these bacteria inside the plant must be further investigated in order to understand their population dynamics within the host.(AU)

Archaea diversity in vegetation gradients from the Brazilian Cerrado

We used 16S rRNA sequencing to assess the archaeal communities across a gradient of Cerrado. The archaeal communities differed across the gradient. Crenarcheota was the most abundant phyla, with Nitrosphaerales and NRPJ as the predominant classes. Euryachaeota was also found across the Cerrado gradient, including the classes Metanocellales and Methanomassiliicoccaceae.(AU)

Using in situ flow cytometry images of ciliates and dinoflagellates for aquatic system monitoring / Usando imagem de citometria de fluxo in situ de ciliados e dinoflagelados para o monitoramento de sistemas aquáticos

Short-period variability in plankton communities is poorly documented, especially for variations occurring in specific groups in the assemblage because traditional analysis is laborious and time-consuming. Moreover, it does not allow the high sampling frequency required for decision making. To overcome this limitation, we tested the submersible CytoSub flow cytometer. This device was anchored at a distance of approximately 10 metres from the low tide line at a depth of 1.5 metres for 12 hours to monitor the plankton at a site in the biological reserve of Barra da Tijuca beach, Rio de Janeiro. Data analysis was performed with two-dimensional scatter plots, individual pulse shapes and micro images acquisition. High-frequency monitoring results of two interesting groups are shown. The abundance and carbon biomass of ciliates were relatively stable, whereas those from dinoflagellates were highly variable along the day. The linear regression of biovolume measures between classical microscopy and in situ flow cytometry demonstrate high degree of adjustment. Despite the success of the trial and the promising results obtained, the large volume of images generated by the method also creates a need to develop pattern recognition models for automatic classification of in situ cytometric images.(AU)

A variabilidade de curto período em comunidades do plâncton é pouco documentada, especialmente as variações que ocorrem em grupos específicos das assembleias por causa das análises tradicionais serem muito trabalhosas e demoradas. Além disso, não permitem que a alta frequência amostral necessária para a tomada de decisão. Para superar esta limitação, nós testamos o CytoSub, um citômetro de fluxo submersível. Este aparelho foi ancorado a aproximadamente 10 metros de distância da linha de maré baixa a uma profundidade de 1,5 metros por 12 horas para monitorar o plâncton em um sítio da reserva biológica da praia da Barra da Tijuca, Rio de Janeiro. A análise dos dados foi realizada a partir de gráficos de dispersão bidimensionais, pelas assinaturas ópticas individuais escaneadas (pulse shape profile) e aquisição de micro imagens. Resultados do monitoramento de alta frequência de dois grupos interessantes são apresentados. A abundância e a biomassa de carbono de um grupo de ciliados foram relativamente estáveis, ao passo que o grupo de dinoflagelado, foi altamente variável ao longo do dia. O modelo de regressão linear das medidas de biovolume entre a clássica microscopia e a citometria de fluxo in situ apresentou alto grau de ajustamento. Apesar do sucesso deste ensaio e dos resultados promissores obtidos, o grande volume de imagens geradas por este método também gerou a necessidade de se desenvolver modelos de reconhecimento de padrões para a classificação automática de imagens de citometria in situ.(AU)

Replacement of native vegetation alters the soil microbial structure in the Pampa biome

Land use change is one of the the major factors related to soil degradation and alterations in soil microbial diversity and structure. In this study, we aimed to evaluate the microbial shifts caused by deforestation of a small area of a natural forest for the introduction of a pasture in the Brazilian Pampa. The microbial abundance and structure were evaluated by molecular approaches based on quantitative Polymerase Chain Reaction (qPCR) and Ribosomal Intergenic Spacer Analysis (RISA). The microbial communities did not present significant quantitative differences, but the environmental impact caused by deforestation changed the structure of the bacterial and archaeal communities. Taking into account the percentage of shared OTUs (operational taxonomic units) of each domain evaluated, we concluded that the domain Bacteria were more influenced by the deforestation than the Archaea. A total of 22 % of bacterial OTUs and 50 % of the archaeal OTUs were shared between forest and grassland leading us to conclude that the environment evaluated presented a core microbial community that did not suffer modification caused by land use change.

Replacement of native vegetation alters the soil microbial structure in the Pampa biome

Land use change is one of the the major factors related to soil degradation and alterations in soil microbial diversity and structure. In this study, we aimed to evaluate the microbial shifts caused by deforestation of a small area of a natural forest for the introduction of a pasture in the Brazilian Pampa. The microbial abundance and structure were evaluated by molecular approaches based on quantitative Polymerase Chain Reaction (qPCR) and Ribosomal Intergenic Spacer Analysis (RISA). The microbial communities did not present significant quantitative differences, but the environmental impact caused by deforestation changed the structure of the bacterial and archaeal communities. Taking into account the percentage of shared OTUs (operational taxonomic units) of each domain evaluated, we concluded that the domain Bacteria were more influenced by the deforestation than the Archaea. A total of 22 % of bacterial OTUs and 50 % of the archaeal OTUs were shared between forest and grassland leading us to conclude that the environment evaluated presented a core microbial community that did not suffer modification caused by land use change.(AU)

Using in situ flow cytometry images of ciliates and dinoflagellates for aquatic system monitoring

Abstract Short-period variability in plankton communities is poorly documented, especially for variations occurring in specific groups in the assemblage because traditional analysis is laborious and time-consuming. Moreover, it does not allow the high sampling frequency required for decision making. To overcome this limitation, we tested the submersible CytoSub flow cytometer. This device was anchored at a distance of approximately 10 metres from the low tide line at a depth of 1.5 metres for 12 hours to monitor the plankton at a site in the biological reserve of Barra da Tijuca beach, Rio de Janeiro. Data analysis was performed with two-dimensional scatter plots, individual pulse shapes and micro images acquisition. High-frequency monitoring results of two interesting groups are shown. The abundance and carbon biomass of ciliates were relatively stable, whereas those from dinoflagellates were highly variable along the day. The linear regression of biovolume measures between classical microscopy and in situ flow cytometry demonstrate high degree of adjustment. Despite the success of the trial and the promising results obtained, the large volume of images generated by the method also creates a need to develop pattern recognition models for automatic classification of in situ cytometric images.

Resumo A variabilidade de curto período em comunidades do plâncton é pouco documentada, especialmente as variações que ocorrem em grupos específicos das assembleias por causa das análises tradicionais serem muito trabalhosas e demoradas. Além disso, não permitem que a alta frequência amostral necessária para a tomada de decisão. Para superar esta limitação, nós testamos o CytoSub, um citômetro de fluxo submersível. Este aparelho foi ancorado a aproximadamente 10 metros de distância da linha de maré baixa a uma profundidade de 1,5 metros por 12 horas para monitorar o plâncton em um sítio da reserva biológica da praia da Barra da Tijuca, Rio de Janeiro. A análise dos dados foi realizada a partir de gráficos de dispersão bidimensionais, pelas assinaturas ópticas individuais escaneadas (pulse shape profile) e aquisição de micro imagens. Resultados do monitoramento de alta frequência de dois grupos interessantes são apresentados. A abundância e a biomassa de carbono de um grupo de ciliados foram relativamente estáveis, ao passo que o grupo de dinoflagelado, foi altamente variável ao longo do dia. O modelo de regressão linear das medidas de biovolume entre a clássica microscopia e a citometria de fluxo in situ apresentou alto grau de ajustamento. Apesar do sucesso deste ensaio e dos resultados promissores obtidos, o grande volume de imagens geradas por este método também gerou a necessidade de se desenvolver modelos de reconhecimento de padrões para a classificação automática de imagens de citometria in situ.

Using in situ flow cytometry images of ciliates and dinoflagellates for aquatic system monitoring

Abstract Short-period variability in plankton communities is poorly documented, especially for variations occurring in specific groups in the assemblage because traditional analysis is laborious and time-consuming. Moreover, it does not allow the high sampling frequency required for decision making. To overcome this limitation, we tested the submersible CytoSub flow cytometer. This device was anchored at a distance of approximately 10 metres from the low tide line at a depth of 1.5 metres for 12 hours to monitor the plankton at a site in the biological reserve of Barra da Tijuca beach, Rio de Janeiro. Data analysis was performed with two-dimensional scatter plots, individual pulse shapes and micro images acquisition. High-frequency monitoring results of two interesting groups are shown. The abundance and carbon biomass of ciliates were relatively stable, whereas those from dinoflagellates were highly variable along the day. The linear regression of biovolume measures between classical microscopy and in situ flow cytometry demonstrate high degree of adjustment. Despite the success of the trial and the promising results obtained, the large volume of images generated by the method also creates a need to develop pattern recognition models for automatic classification of in situ cytometric images.

Resumo A variabilidade de curto período em comunidades do plâncton é pouco documentada, especialmente as variações que ocorrem em grupos específicos das assembleias por causa das análises tradicionais serem muito trabalhosas e demoradas. Além disso, não permitem que a alta frequência amostral necessária para a tomada de decisão. Para superar esta limitação, nós testamos o CytoSub, um citômetro de fluxo submersível. Este aparelho foi ancorado a aproximadamente 10 metros de distância da linha de maré baixa a uma profundidade de 1,5 metros por 12 horas para monitorar o plâncton em um sítio da reserva biológica da praia da Barra da Tijuca, Rio de Janeiro. A análise dos dados foi realizada a partir de gráficos de dispersão bidimensionais, pelas assinaturas ópticas individuais escaneadas (pulse shape profile) e aquisição de micro imagens. Resultados do monitoramento de alta frequência de dois grupos interessantes são apresentados. A abundância e a biomassa de carbono de um grupo de ciliados foram relativamente estáveis, ao passo que o grupo de dinoflagelado, foi altamente variável ao longo do dia. O modelo de regressão linear das medidas de biovolume entre a clássica microscopia e a citometria de fluxo in situ apresentou alto grau de ajustamento. Apesar do sucesso deste ensaio e dos resultados promissores obtidos, o grande volume de imagens geradas por este método também gerou a necessidade de se desenvolver modelos de reconhecimento de padrões para a classificação automática de imagens de citometria in situ.

Characterization of Enterococcus spp. isolated from a fish farming environment in southern Brazil

Abstract The aim of present study is to characterize the resistance and virulence profile of enterococci isolated from aquaculture excavated ponds and masonry tanks (6 samples) in southern Brazil. Samples were cultured in selective medium, 10 colonies were randomly selected from each sample, which were identified by MALDI-TOF and tested against 13 antimicrobials. The presence of resistance (tetL, tetM, tetS, ermB and msrC) and virulence (ace, esp, agg, cylA and gelE) genes were determined by PCR. A total of 79 enterococci were identified, and Entecococcus faecalis (44.3%) and E. casseliflavus (36.7%) were the most prevalent species isolated. Sixty-five strains (82.3%) were resistant to at least one of the antimicrobials tested, whereas 27 (34.2%) strains were multiresistant. The overall percentages of antimicrobial resistant isolates were: 58.2% to rifampicin, 40.5% to fluoroquinolones, 36.7% to erythromycin and 30.4% to tetracycline. The tetL and tetM genes were found in 57.7% of the tetracycline-resistant strains; and msrC in 31.01% of erythromycin-resistant strains. The most frequently detected virulence factors were ace and gelE genes. Although limited to a single farm, these data suggest that aquaculture may be a reservoir of resistant and virulent enterococci. This study is the first step towards enhancing our understandingof distribution, resistance and virulence profile in enterococci isolated from fish farming environments in the south Brazil.

Resumo O objetivo do estudo apresentado é caracterizar o perfil de resistência e virulência de enterococos isolados de viveiros escavados e tanques de alvenaria (6 amostras) de uma pisicultura no Sul do Brasil. As amostras foram cultivadas em meio seletivo, 10 colônias foram selecionadas aleatoriamente de cada amostra, que foram identificadas por MALDI-TOF e testadas contra 13 antimicrobianos. A presença de genes de resistência (tetL, tetM, tetS, ermB e msrC) e virulência (ace, esp, agg, cylA e gelE) foi determinada por PCR. Foram identificados 79 enterococos, sendo Entecococcus faecalis (44,3%) e E. casseliflavus (36,7%) as espécies mais frequentes isoladas. Sessenta e cinco cepas (82,3%) eram resistentes a pelo menos um dos antimicrobianos testados, enquanto 27 (34,2%) eram multirresistentes. As porcentagens gerais de isolados resistentes a antimicrobianos foram: 58,2% para rifampicina, 40,5% para fluoroquinolonas, 36,7% para eritromicina e 30,4% para tetraciclina. Os genes tetL e tetM foram encontrados em 57,7% das cepas resistentes à tetraciclina; e msrC em 31,01% das cepas resistentes à eritromicina. Os fatores de virulência mais comumente detectados foram ace e gelE. Embora limitados a uma única fazenda, esses dados indicam que a aquicultura pode ser uma fonte de enterococos resistentes e virulentos. Este estudo é o primeiro passo para melhorar nosso entendimento da distribuição, resistência e perfil de virulência em enterococos isolados de ambientes de piscicultura no sul do Brasil.

Ecologia da comunidade de helmintos gastrointestinais de tartarugas-verdes ( Chelonia mydas ) recolhidas no litoral do Espírito Santo / Community ecology of gastrointestinal helminths from green turtles (Chelonia mydas) collected in the coast of Espírito Santo

A tartaruga-verde, Chelonia mydas, apresenta distribuição cosmopolita. No Brasil, ocorre na costa, porém desova em ilhas oceânicas. A helmintofauna de tartarugas-verdes é diversificada, podendo-se dizer que tem a maior diversidade comparada com outras espécies de tartarugas. Objetivou-se avaliar aspectos ecológicos da comunidade de helmintos gastrointestinais e relacionar com a condição corporal de tartarugas-verdes recolhidas no litoral do Espírito Santo. Foram utilizados 36 exemplares juvenis da espécie C. mydas. O trato gastrointestinal foi separado e dividido em porções: esôfago/estômago, intestino delgado e intestino grosso. Cada porção foi inspecionada à procura de parasitos, e os exemplares encontrados foram separados para posterior identificação. Das 36 tartarugas avaliadas, 34 estavam parasitadas por helmintos (94,44%), com um total de 10.734 helmintos. Foram encontradas 18 espécies de trematodas pertencentes a quatro famílias. A riqueza de espécies encontrada foi de 4,29±2,19 (1-10) e a intensidade média de infecção foi de 315,64±281,83 (2-994) helmintos. Os parasitos mais prevalentes foram Cricocephalus albus, Metacetabulum invaginatum e Neoctangium travassosi, ambos com 61,11% (22/36), Pronocephalus obliquus com 33,33% (12/36), e Glyphicephalus lobatus com 30,55% (11/36). O helminto mais abundante foi M. invaginatum com 70,63 helmintos/animal, seguido de C. albus com 58,77 helmintos/animal e N. travassosi com 41,75 helmintos/animal.(AU)

The green turtle, Chelonia mydas has worldwide distribution. In Brazil, it is found on the coast, but spawning occurs on oceanic islands. The helminth fauna of green turtles is diverse and has the greatest diversity when compared with other species of turtles. This study aims to evaluate ecological aspects of gastrointestinal helminth community and connect to the body condition of green turtles collected on the coast of Espírito Santo. A total of 36 juvenile specimens of the species C. mydas were used. The gastrointestinal tract was removed and divided into portions: esophagus/stomach, small intestine and large intestine. Each portion was inspected looking for parasites and the specimens found were separated for later identification. Of the 36 turtles evaluated, 34 were parasitized by helminths (94.44%), with a total of 10,734 helminths. Results include findings of 18 species of trematodes belonging to four families. The species richness was 4,29 ± 2,19 (1-10) and the mean intensity of infection was 315,64 ± 281,83 (2-994) helminths. The prevalent parasites were Cricocephalus albus, Metacetabulum invaginatum and Neoctangium travassosi, both with 61,11% (22/36), Pronocephalus obliquus with 33,33% (12/36), and Glyphicephalus lobatus with 30,55% (11/36). The abundant helminth was Metacetabulum invaginatum with helminths 70,63/animal, followed by C. albus with helminths 58,77/animal and N. travassosi with helminths 41,75/animal.(AU)

Earthworms (Amynthas spp. ) increase common bean growth, microbial biomass, and soil respiration / Minhocas (Amynthas spp. ) aumentam o crescimento do feijoeiro, a biomassa microbiana e a respiração do solo

Few studies have evaluated the effect of earthworms on plants and biological soil attributes, especially among legumes. The objective of this study was to evaluate the influence of earthworms (Amynthas spp.) on growth in the common bean (Phaseolus vulgaris L.) and on soil biological attributes. The experiment was conducted in a greenhouse using a completely randomized design with five treatments and eight repetitions. The treatments consisted of inoculation with five different quantities of earthworms of the genus Amynthas (0, 2, 4, 6, and 8 worms per pot). Each experimental unit consisted of a plastic pot containing 4 kg of soil and two common bean plants. The experiment was harvested 38 days after seedling emergence. Dry matter and plant height, soil respiration, microbial respiration, microbial biomass, and metabolic quotient were determined. Earthworm recovery in our study was high in number and mass, with all values above 91.6% and 89.1%, respectively. In addition, earthworm fresh biomass decreased only in the treatment that included eight earthworms per pot. The presence of earthworms increased the plant growth and improved soil biological properties, suggesting that agricultural practices that favor the presence of these organisms can be used to increase the production of common bean, and the increased soil CO2 emission caused by the earthworms can be partially offset by the addition of commonbean crop residues to the soil.(AU)

Poucos estudos têm avaliado o efeito de minhocas nas plantas e nos atributos biológicos do solo, principalmente em plantas leguminosas, como o feijoeiro (Phaseolus vulgaris L.). Assim, o objetivo deste trabalho foi avaliar a influência de minhocas (Amynthas spp.) no crescimento do feijoeiro e nos atributos biológicos do solo. O experimento foi realizado em casa de vegetação em delineamento completamente casualizado, com cinco tratamentos e oito repetições. Os tratamentos foram constituídos de cinco níveis de inoculação (0, 2, 4, 6 e 8 minhocas por vaso) de minhocas do gênero Amynthas spp. Cada unidade experimental foi composta por um vaso de plástico, contendo 4 kg de solo e duas plantas de feijoeiro. O período experimental foi encerrado após 38 dias da emergência das plantas. Foram determinadas a matéria seca e a altura das plantas, a respiração edáfica, a respiração microbiana, a biomassa microbiana do solo e o quociente metabólico. A recuperação de minhocas foi alta em número e massa, com todos os valores acima de 91,6% e 89,1%, respectivamente. Adicionalmente, a massa de minhocas diminuiu apenas no tratamento com oito minhocas por vaso. A presença de minhocas aumentou o crescimento da planta e atributos biológicos do solo, sugerindo que práticas agrícolas que favoreçam a presença de minhocas podem vir a ser utilizadas para aumentar a produção de feijoeiro e, a elevação da emissão de CO2 causada pelas minhocas pode ser parcialmente mitigada pela adição deresíduos culturais de feijoeiro no solo.(AU)

Ecologia da comunidade de helmintos gastrointestinais de tartarugas-verdes (Chelonia mydas) recolhidas no litoral do Espírito Santo / Community ecology of gastrointestinal helminths from green turtles (Chelonia mydas) collected in the coast of Espírito Santo

A tartaruga-verde, Chelonia mydas, apresenta distribuição cosmopolita. No Brasil, ocorre na costa, porém desova em ilhas oceânicas. A helmintofauna de tartarugas-verdes é diversificada, podendo-se dizer que tem a maior diversidade comparada com outras espécies de tartarugas. Objetivou-se avaliar aspectos ecológicos da comunidade de helmintos gastrointestinais e relacionar com a condição corporal de tartarugas-verdes recolhidas no litoral do Espírito Santo. Foram utilizados 36 exemplares juvenis da espécie C. mydas. O trato gastrointestinal foi separado e dividido em porções: esôfago/estômago, intestino delgado e intestino grosso. Cada porção foi inspecionada à procura de parasitos, e os exemplares encontrados foram separados para posterior identificação. Das 36 tartarugas avaliadas, 34 estavam parasitadas por helmintos (94,44%), com um total de 10.734 helmintos. Foram encontradas 18 espécies de trematodas pertencentes a quatro famílias. A riqueza de espécies encontrada foi de 4,29±2,19 (1-10) e a intensidade média de infecção foi de 315,64±281,83 (2-994) helmintos. Os parasitos mais prevalentes foram Cricocephalus albus, Metacetabulum invaginatum e Neoctangium travassosi, ambos com 61,11% (22/36), Pronocephalus obliquus com 33,33% (12/36), e Glyphicephalus lobatus com 30,55% (11/36). O helminto mais abundante foi M. invaginatum com 70,63 helmintos/animal, seguido de C. albus com 58,77 helmintos/animal e N. travassosi com 41,75 helmintos/animal.(AU)

The green turtle, Chelonia mydas has worldwide distribution. In Brazil, it is found on the coast, but spawning occurs on oceanic islands. The helminth fauna of green turtles is diverse and has the greatest diversity when compared with other species of turtles. This study aims to evaluate ecological aspects of gastrointestinal helminth community and connect to the body condition of green turtles collected on the coast of Espírito Santo. A total of 36 juvenile specimens of the species C. mydas were used. The gastrointestinal tract was removed and divided into portions: esophagus/stomach, small intestine and large intestine. Each portion was inspected looking for parasites and the specimens found were separated for later identification. Of the 36 turtles evaluated, 34 were parasitized by helminths (94.44%), with a total of 10,734 helminths. Results include findings of 18 species of trematodes belonging to four families. The species richness was 4,29 ± 2,19 (1-10) and the mean intensity of infection was 315,64 ± 281,83 (2-994) helminths. The prevalent parasites were Cricocephalus albus, Metacetabulum invaginatum and Neoctangium travassosi, both with 61,11% (22/36), Pronocephalus obliquus with 33,33% (12/36), and Glyphicephalus lobatus with 30,55% (11/36). The abundant helminth was Metacetabulum invaginatum with helminths 70,63/animal, followed by C. albus with helminths 58,77/animal and N. travassosi with helminths 41,75/animal.(AU)

Microbial interactions: ecology in a molecular perspective

The microorganism-microorganism or microorganism-host interactions are the key strategy to colonize and establish in a variety of different environments. These interactions involve all ecological aspects, including physiochemical changes, metabolite exchange, metabolite conversion, signaling, chemotaxis and genetic exchange resulting in genotype selection. In addition, the establishment in the environment depends on the species diversity, since high functional redundancy in the microbial community increases the competitive ability of the community, decreasing the possibility of an invader to establish in this environment. Therefore, these associations are the result of a co-evolution process that leads to the adaptation and specialization, allowing the occupation of different niches, by reducing biotic and abiotic stress or exchanging growth factors and signaling. Microbial interactions occur by the transference of molecular and genetic information, and many mechanisms can be involved in this exchange, such as secondary metabolites, siderophores, quorum sensing system, biofilm formation, and cellular transduction signaling, among others. The ultimate unit of interaction is the gene expression of each organism in response to an environmental (biotic or abiotic) stimulus, which is responsible for the production of molecules involved in these interactions. Therefore, in the present review, we focused on some molecular mechanisms involved in the microbial interaction, not only in microbial-host interaction, which has been exploited by other reviews, but also in the molecular strategy used by different microorganisms in the environment that can modulate the establishment and structuration of the microbial community.(AU)

Microbial interactions: ecology in a molecular perspective

ABSTRACT The microorganism-microorganism or microorganism-host interactions are the key strategy to colonize and establish in a variety of different environments. These interactions involve all ecological aspects, including physiochemical changes, metabolite exchange, metabolite conversion, signaling, chemotaxis and genetic exchange resulting in genotype selection. In addition, the establishment in the environment depends on the species diversity, since high functional redundancy in the microbial community increases the competitive ability of the community, decreasing the possibility of an invader to establish in this environment. Therefore, these associations are the result of a co-evolution process that leads to the adaptation and specialization, allowing the occupation of different niches, by reducing biotic and abiotic stress or exchanging growth factors and signaling. Microbial interactions occur by the transference of molecular and genetic information, and many mechanisms can be involved in this exchange, such as secondary metabolites, siderophores, quorum sensing system, biofilm formation, and cellular transduction signaling, among others. The ultimate unit of interaction is the gene expression of each organism in response to an environmental (biotic or abiotic) stimulus, which is responsible for the production of molecules involved in these interactions. Therefore, in the present review, we focused on some molecular mechanisms involved in the microbial interaction, not only in microbial-host interaction, which has been exploited by other reviews, but also in the molecular strategy used by different microorganisms in the environment that can modulate the establishment and structuration of the microbial community.

USO DE TANINOS CONDENSADOS EM SUÍNOS RECÉM DESMAMADOS DESAFIADOS COM UMA DIETA SIMPLES

Dietas simples oferecem um desafio aos animais principalmente na fase pós desmame, o que pode levar a diversos distúrbios do trato gastrointestinal causados por fatores nutricionais ou pela formação de um ambiente propício ao desenvolvimento de patógenos, podendo ter como resultado a presença de diarreia. Compostos de tanino condensado podem atuar de maneira benéfica nestas circunstâncias. O objetivo do trabalho foi avaliar o efeito de um composto de taninos condensados para suínos com 21 dias de idade, recebendo uma dieta simples. Foi avaliado desempenho, digestibilidade aparente do trato total, escore fecal e presença de diarreia, microbioma intestinal e duas citocinas anti-inflamatórias (IL-4 e IL-10). Foram utilizados 32 leitões, peso médio de 6,3 ± 0,78, oito animais por tratamento, assim distribuídos: Controle negativo - dieta basal com 80 ppm de ZnO; Controle Positivo - dieta basal com 2500 ppm de ZnO; Taninos condensados 1 e 2 g/kg de ração Controle negativo com inclusão de 1 g/kg ou 2 g/kg de composto de taninos condensados. Foram formuladas dietas para as fases pré-inicial (1 a 14 dias pós-desmame) e inicial (15 a 28 dias pós-desmame), com 70 e 35 g/kg de lactose e 360 a 373 g/kg de farelo de soja, respectivamente e sem zinco suplementar. No total foram 28 dias de experimento que finalizou com animais com 49 dias de idade. Foram feitas medidas de peso e de consumo aos 0, 7, 14, 21 e 28 dias pós desmame, e sobras de ração foram medidas diariamente. Com estes dados foram obtidas as medidas de desempenho (consumo de ração, ganho de peso e conversão alimentar). Entre 7 e 14 e 21 e 28 dias pós desmame foram feitas coleta de fezes e urina para avaliação da digestibilidade aparente do trato total para matéria seca, energia, proteína, retenção de nitrogênio e metabolizabilidade da energia. A ocorrência de diarreia e avaliação do escore fecal foi feita diariamente. Ao final do experimento, quatro animais por tratamento, foram eutanasiados e as seções do trato gastrintestinal foram identificadas e isoladas para evitar trânsito de conteúdo. Uma amostra de 3 mL do conteúdo cecal foi coletada para análise de microbioma intestinal e um segmento de 5 cm do trato, situado entre o jejuno-íleo para análise de citocinas anti-inflamatórias (IL-4 e IL-10), ambos armazenados a -80ºC. Do conteúdo cecal foi extraído o DNA com o kit ZR fecal DNA MiniPrep da Zymo®, quantificado, amplificado e seqüenciado pelo MiSeq Illumina® e posteriormente analisado na plataforma QIIME (Quantitative Insights Into Microbial Ecology). A análise de citocinas foi feita através de qPCR, utilizando primers específicos para cada alvo. Foram feitas as análises estatísticas no software MiniTab de acordo com cada variável. Não foram encontradas diferenças entre os tratamentos para nenhuma resposta de desempenho nos períodos avaliados. Também não houve diferenças para as respostas de digestibilidade e metabolizabilidade. As fezes produzidas pelos leitões que receberam dietas com taninos apresentaram-se mais úmidas (p<0,01). Os tratamentos não influenciaram maior produção de IL-4 e IL-10 aos 28 dias. No entanto, o tratamento com 2 g/kg de composto de taninos condensados, proporcionou uma maior razão Firmicutes/Bacteroidetes o que indica modulação benéfica na microbiota gastrintestinal. O mesmo tratamento mostrou maior incidência dos gêneros Mitsuokella e Acidaminococcus, que podem ser benéficos ao desempenho. O uso de taninos condensados sobretudo no nível de 2 g/kg de ração apresenta benefícios para os leitões em situação de desafio intestinal.1

Simple diets offer a challenge to animals especially in the post-weaning phase, which can lead to various disorders of the gastrointestinal tract caused by nutritional factors or the formation of an environment prone to the development of pathogens, that could result in the presence of diarrhea. Condensed tannin compounds can act beneficially in these circumstances. The objective of this study was to evaluate the effect of a compound of condensed tannins for pigs at 21 days of age, receiving a simple diet. Performance, apparent digestibility of the total tract, fecal score and presence of diarrhea, intestinal microbiome and two anti-inflammatory cytokines (IL-4 and IL-10) were evaluated. Thirty-two piglets, initial average weight of 6.3 ±0.78, eight animals per treatment, distributed were: Negative control - basal diet with 80 ppm of zinc oxide; Positive Control - basal diet with 2500 ppm of zinc oxide; Condensed Tannins 1 and 2 g/kg of feed - Negative control with inclusion of 1 g/kg or 2 g/kg of condensed tannin compound. Diets were formulated for pre-initial (1 to 14 days post-weaning) and initial phases (15 to 28 days after weaning) with 70 and 35 g/kg of lactose, 360 to 373 g/kg soybean meal, respectively, both with no supplementary zinc level. In total there were 28 days of experiment that ended with 49 days old piglets. Weight and intake measures were taken at 0, 7, 14, 21 and 28 days after weaning, and feed leftovers were measured daily. With these data, performance measures were obtained (feed intake, weight gain and feed conversion). Between 7 to 14 and 21 to 28 days after weaning, feces and urine were collected to assess the apparent digestibility of the total tract for dry matter, energy, protein, nitrogen retention and energy metabolizability. The occurrence of diarrhea and the evaluation of fecal score was taken daily. At the end of the experiment, four animals per treatment were euthanized and sections of the gastrointestinal tract were identified and isolated to avoid transit of content. A sample of 3 mL of cecal content and a 5 cm segment of the tract, located between the jejuno-ileum were collected and stored at -80ºC for intestinal microbiome and anti-inflammatory cytokines (IL-4 and IL-10) analysis, respectively. From the cecal content DNA was extracted by Zymo DNA MiniPrep fecal ZR kit®. quantified, amplified and sequenced by "MiSeq" Illumina® and subsequently analyzed on the QIIME (Quantitative Insights Into Microbial Ecology) platform. Cytokine scans were performed using qPCR, using primers specific to each target. Statistical analyses were performed in the MiniTab software according to each variable. No differences were found between treatments for any performance response in the evaluated periods. There were also no differences for digestibility and metabolizability responses. The feces produced by piglets that received diets with tannins were wetter (P<0.01). The treatments did not influence higher production of IL-4 and IL-10 at 28 days. However, the treatment with 2 g/kg of condensed tannin compound provided a higher Firmicutes/Bacteroidetes ratio, which indicates beneficial modulation in the gastrointestinal microbiota. The same treatment showed a higher incidence of the genera Mitsuokella and Acidaminococcus, which may be beneficial to performance. The use of condensed tannins mainly at the level of 2 g/kg of feed has benefits for piglets in a challenging intestinal media.2

Growth performance, carcass yield and intestinal microflora populations of broilers fed diets containing thepax and yogurt

The present study aimed at evaluating the effect of the probiotic thepax and yogurt (as probiotic) on the growth response and intestinal microflora results of broiler chickens. Two hundred forty day-old Ross 308 broilers were equally distributed into 12 floor pens and reared for 42 day. The treatments consisted of yogurt (10, 5 and 2.5% during starter, grower and finisher periods in the drinking water, respectively) and thepax (1000, 500, 250 g/ton-1 in the starter, grower and finisher diets, respectively), resulting three experimental diets and a control group. Each dietary treatment was fed ad-libitum to four replicate group of 20 birds at the beginning of rearing period. Birds and feed were weighed on days 21 and 42. The results of experiment indicate that diets containing feed additives improved broiler performance. The body weight gain and feed conversion ratio improved significantly more (p 0.05) with the thepax treatment compared with the control broilers during the total rearing period. The highest (p 0.05) carcass and thigh values were recorded for broilers fed the diet supplemented with thepax and yogurt, respectively. The lowest abdominal fat pad value was obtained in broilers fed the diet supplemented with thepax. On d 21, thepax and yogurt significantly reduced (p 0.05) cecal Escherichia coli and Clostridium perfringens populations compared with the control group. In conclusion, thepax and yogurt improved broilers growth response and conferred intestinal health benefits to chickens by improving their microbial ecology.

Growth performance, carcass yield and intestinal microflora populations of broilers fed diets containing thepax and yogurt

The present study aimed at evaluating the effect of the probiotic thepax and yogurt (as probiotic) on the growth response and intestinal microflora results of broiler chickens. Two hundred forty day-old Ross 308 broilers were equally distributed into 12 floor pens and reared for 42 day. The treatments consisted of yogurt (10, 5 and 2.5% during starter, grower and finisher periods in the drinking water, respectively) and thepax (1000, 500, 250 g/ton-1 in the starter, grower and finisher diets, respectively), resulting three experimental diets and a control group. Each dietary treatment was fed ad-libitum to four replicate group of 20 birds at the beginning of rearing period. Birds and feed were weighed on days 21 and 42. The results of experiment indicate that diets containing feed additives improved broiler performance. The body weight gain and feed conversion ratio improved significantly more (p 0.05) with the thepax treatment compared with the control broilers during the total rearing period. The highest (p 0.05) carcass and thigh values were recorded for broilers fed the diet supplemented with thepax and yogurt, respectively. The lowest abdominal fat pad value was obtained in broilers fed the diet supplemented with thepax. On d 21, thepax and yogurt significantly reduced (p 0.05) cecal Escherichia coli and Clostridium perfringens populations compared with the control group. In conclusion, thepax and yogurt improved broilers growth response and conferred intestinal health benefits to chickens by improving their microbial ecology.

DIVERSIDADE BACTERIANA DO INTESTINO DE TILÁPIA-DO-NILO (Oreochromis niloticus), PROVENIENTE DE DIFERENTES REGIÕES DO BRASIL

A microbiota intestinal dos peixes apresenta grande influência na qualidade de vida destes animais. Uma composição microbiana bem estabelecida melhora as respostas imunológicas contra microrganismos patogênicos, além de conferir melhor digestão dos nutrientes. O objetivo do trabalho foi comparar a diversidade ecológica bacteriana obtida de intestinos de tilápia-do-nilo (Oreochromis niloticus), provenientes de distintas regiões do Brasil (sul, sudeste e nordeste) e relacionar com o ambiente e sistema de criação dos peixes. Para tanto, o intestino médio foi coletado em pisciculturas comerciais, nos municípios de Toledo - PR, Santa Fé do Sul SP e Paulo Afonso BA, totalizando 90 amostras intestinais. O DNA bacteriano, presente no intestino, foi extraído, purificado e amplificado por PCR. Os amplicons obtidos foram separados por Eletroforese em Gel de Gradiente Desnaturante (DGGE), resultando em um gel para as amostras de cada cidade. Os géis foram escaneados e analisados em software específico. A análise de agrupamento foi representada com a construção de um dendograma para se observar as distâncias entre as diferentes amostras. Parâmetros ecológicos foram calculados e comparou-se o índice de diversidade de Shannon, riqueza, habitabilidade e equitabilidade entre as amostras dos três géis. Observou-se no dendograma que a maioria das amostras coletadas em Toledo apresentaram apenas 7,7% de similaridade com a estrutura da comunidade microbiana intestinal dos peixes provenientes de Paulo Afonso e Santa Fé do Sul. As amostras provenientes de Paulo Afonso obtiveram maior índice de diversidade, sendo estatisticamente diferente daquelas de Toledo. O índice de habitabilidade das amostras de Toledo foi estatisticamente diferente das amostras de Paulo Afonso e Santa Fé do Sul. A riqueza não foi diferente estatisticamente (P>0,05) entre as amostras obtidas das três cidades e para Paulo Afonso, Santa Fé do Sul e Toledo, foram encontrados, respectivamente, um total de 18, 22, 24 Unidades Taxonômicas Operacionais (UTOs). Por último, a equitabilidade foi significativamente maior nas amostras obtidas em Paulo Afonso. Portanto, a microbiota intestinal se altera, dependendo do local e sistema (tanque-rede e viveiro escavado) em que as tilápias são cultivadas.

The fish intestinal microbiota has a great influence on these animals quality of life. A well-established microbial composition improves immune responses against pathogenic microorganisms, as well as improving digestion of nutrients. This work aimed to compare the bacterial ecological diversity from Nile tilapia (Oreochromis niloticus) intestines collected from different regions of Brazil (south, southeast and northeast) and its relationship to environment and raise system. Thus, the medium intestine, of 90 fish, was collected from different commercial farms, in Toledo - PR, Santa Fé do Sul - SP and Paulo Afonso BA cities. DNA of all bacteria harboring in fish gut was extracted, purified and amplified by PCR. The obtained amplicons were separated by Denaturing Gradient Gel Electrophoresis (DGGE), resulting in a gel for the samples of each city. The gels were scanned and analyzed by specific software. The cluster analysis was represented by the construction of a dendogram to observe the distances between the different samples. Ecological parameters were calculated and the Shannon diversity index, richness, habitability and equitability were compared between samples of the three gels. It was observed that the majority of samples collected in Toledo presented only 7.7% similarity in relation to fish intestinal bacteria community from Paulo Afonso and Santa Fé do Sul. Samples from Paulo Afonso showed higher (P<0.05) diversity index, than Toledo. The habitability index from Toledo samples was statistically different from Paulo Afonso and Santa Fé do Sul. The richness did not present statistical difference (P>0.05) between the three cities and for Paulo Afonso, Santa Fé do Sul and Toledo, were found, respectively, a total of 18, 22, 24 Operational Taxonomic Units (OTUs). Finally, the equitability of Paulo Afonso samples was significantly higher than other cities. Therefore, the intestinal microbiota changes, depending on the region (city) and system (net cage and excavated pond) in which tilapias are reared