RESUMO

Worldwide coffee production is threatened by climate change, which highlights the importance of heat tolerance studies. Here we tested the hypothesis that photosynthetic heat tolerance in coffee varieties changes according to acclimation to distinct light conditions. Furthermore, we tested if heat tolerance is associated with the habitat of origin of the coffee species. We evaluated heat tolerance using chlorophyll fluorescence in varieties of Coffea arabica (Mundo Novo and Catuai Amarelo) and C. canephora (Conilon) grown in a common garden under two conditions: high (HS) and low (LS) sunlight. Leaf traits associated with leaf cooling were evaluated in plants grown in LS and HS and associations of heat tolerance with these traits were determined. The varieties tested had high photosynthetic heat tolerance, with temperatures above 54 °C leading to a 50% reduction in Fv /Fm (T50 ). The heat tolerance of each Coffea variety was unaffected by growth in distinct light conditions. Leaves of plants grown in LS were larger and had a lower fraction of the leaf area occupied by stomata (nast ). Heat tolerance was positively associated with leaf size and negatively with nast . C. canephora exhibited higher heat tolerance than C. arabica. The limited plasticity of heat tolerance in response to acclimation under distinct light conditions contradicts the prediction that plants acclimated to HS would have higher photosynthetic heat tolerance than those acclimated to LS. Our results on heat tolerance among Coffea species/varieties in HS and LS indicate the possibility of selection of varieties for better acclimation to ongoing climate changes.

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Polyploidy and whole genome duplication are major evolutionary drivers in plants. Climate variations during the Pleistocene have influenced distribution and range expansion worldwide. Similar trends have been reported for Cerrado plants, but no attempt has been made to link phylogeography with ploidy and breeding changes. Thus, we aimed to (i) assess ploidy and genome size of Eriotheca estevesiae Carv.-Sobr., and compare it with E. pubescens (Mart.) Schott & Endl. (Both included into the Eriotheca Stellate Trichome Species Complex - ESTSC). (ii) Subsequently, we investigated their phylogeography to see whether genetic structure and range expansion trends were similar to those previously described for the Cerrado biome. Finally (iii), we discuss whether ESTSC phylogeographic patterns could be associated with geographic parthenogenesis processes. Common cytogenetic techniques and flow cytometry were used to confirm chromosome number and genome size of E. estevesiae. We used three cpDNA regions to analyse 14 ESTSC Cerrado populations, for which we also obtained ploidy level and breeding information. We investigated haplotype diversity, population structure and tested neutrality, aiming to reconstruct phylogeographic scenarios. We found three ploidy levels and eight cpDNA haplotypes in ESTSC, one shared by most populations. Haplotype and ploidy distribution corroborated that E. pubescens, the widely distributed polyploid and apomictic species, may have originated from northern diploid and probably sexual E. estevesiae. Matrilinear cpDNA links support the idea that apomixis and polyploidy in ESTSC may have allowed range expansion during the Pleistocene, in a process analogous to the geographic parthenogenesis described elsewhere.

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Knowledge of plant responses to environmental heterogeneity during ontogeny is important to elucidate the changes that occur to promote resource capture in tropical forests. We tested the hypothesis that expression changes in leaf metamer traits of Brazilian rosewood (Dalbergia nigra), from seedlings to emergent canopy trees, occur as new microclimate environments are achieved. We also tested the hypothesis that increased light heterogeneity in the understorey leads to higher plasticity in leaf traits of seedlings and saplings than in sun-exposed metamers of emergent trees subject to stressful conditions. We compared leaf metamer traits of 53 individuals including seedlings, saplings and emergent trees. We also evaluated the light heterogeneity in vertical strata and the variations in leaf traits within individuals (among metamers of the same individual). These were associated with height of the individuals. Compared to understorey plants, emergent trees presented larger metamers, with lower specific leaf area (SLA), lower investment in leaf area per total dry mass of metamer (LARm ), lower specific petiole length (SPL) and lower specific internode length (SIL). Higher phenotypic variation within individuals was observed in seedlings, which decreased as the trees grew taller. The results suggest the integration of ontogenetic changes in leaf traits under new microclimate conditions as the plants reach different vertical strata in the forest. Additionally, our results support the hypothesis that increased light heterogeneity in the understorey shaped higher phenotypic variation within individuals in juveniles and that stressful conditions in sun-exposed leaf metamers of emergent trees led to increased phenotypic stability.

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As doenças infecciosas são reconhecidamente causadoras de declínios populacionais de animais silvestres e algumas delas podem representar ameaça à saúde pública. O presente estudo objetivou investigar a ocorrência de Salmonella spp. em Psittaciformes exóticos e nativos mantidos em cativeiro na região central do Rio Grande do Sul, além de comparar os resultados obtidos por meio do método bacteriológico convencional e da reação em cadeia da polimerase (PCR), mediante a utilização de material fecal do ambiente, evitando-se o estresse da contenção. Durante os meses de agosto/2016 e setembro/2016 foram coletadas amostras de fezes frescas de 90 gaiolas em dois criatórios, representando 180 aves. Com as duas técnicas empregadas nas análises, as amostras foram negativas para Salmonella spp., contudo foram detectadas bactérias da família Enterobacteriaceae: Escherichia coli, Cedecea sp. e Citrobacter freundii. Considera-se importante a continuidade do monitoramento dos criatórios, já que o patógeno investigado pode estar em aves portadoras e se manifestar em situações de estresse, representando riscos enquanto zoonose e prejuízos à saúde das aves.(AU)

Infectious diseases are known to cause decline in wildlife population and some of them may represent a threat to public health. This study aimed to investigate the occurrence of Salmonella spp. in exotic and native Psittaciformes kept in captivity in the central region of Rio Grande do Sul, Brazil, and to comparing the results obtained through the conventional bacteriological method and the polymerase chain reaction (PCR), using fecal matter collected from the environment, avoiding the containment stress. From August to September 2016, samples of fresh feces were collected from 90 cages in two breeding grounds, representing 180 birds. According to both analysis techniques the samples were negative for Salmonella spp., however, bacteria from the Enterobacteriaceae family: Escherichia coli, Cedecea sp. and Citrobacter freundii were detected. Continuous monitoring of breeding grounds is important since the pathogen investigated can be found in carrier birds and manifest itself in stressful situations presenting risks such as zoonosis and reduced bird health.(AU)

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RESUMO

As doenças infecciosas são reconhecidamente causadoras de declínios populacionais de animais silvestres e algumas delas podem representar ameaça à saúde pública. O presente estudo objetivou investigar a ocorrência de Salmonella spp. em Psittaciformes exóticos e nativos mantidos em cativeiro na região central do Rio Grande do Sul, além de comparar os resultados obtidos por meio do método bacteriológico convencional e da reação em cadeia da polimerase (PCR), mediante a utilização de material fecal do ambiente, evitando-se o estresse da contenção. Durante os meses de agosto/2016 e setembro/2016 foram coletadas amostras de fezes frescas de 90 gaiolas em dois criatórios, representando 180 aves. Com as duas técnicas empregadas nas análises, as amostras foram negativas para Salmonella spp., contudo foram detectadas bactérias da família Enterobacteriaceae: Escherichia coli, Cedecea sp. e Citrobacter freundii. Considera-se importante a continuidade do monitoramento dos criatórios, já que o patógeno investigado pode estar em aves portadoras e se manifestar em situações de estresse, representando riscos enquanto zoonose e prejuízos à saúde das aves.(AU)

Infectious diseases are known to cause decline in wildlife population and some of them may represent a threat to public health. This study aimed to investigate the occurrence of Salmonella spp. in exotic and native Psittaciformes kept in captivity in the central region of Rio Grande do Sul, Brazil, and to comparing the results obtained through the conventional bacteriological method and the polymerase chain reaction (PCR), using fecal matter collected from the environment, avoiding the containment stress. From August to September 2016, samples of fresh feces were collected from 90 cages in two breeding grounds, representing 180 birds. According to both analysis techniques the samples were negative for Salmonella spp., however, bacteria from the Enterobacteriaceae family: Escherichia coli, Cedecea sp. and Citrobacter freundii were detected. Continuous monitoring of breeding grounds is important since the pathogen investigated can be found in carrier birds and manifest itself in stressful situations presenting risks such as zoonosis and reduced bird health.(AU)

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RESUMO

Since 2008, when the US Environmental Protection Agency (EPA) registered copper and its alloys as an antimicrobial agent for contact surfaces, research has demonstrated their antimicrobial activity. The aim of this study was to evaluate the efficacy of antimicrobial copper against bacteria and fungi isolated from commercial poultry hatcheries in order to develop a microbiological control alternative in these environments. Samples were collected from the surfaces of hatcher baskets from two hatcheries. Mesophilic microorganisms and fungi/yeasts were isolated and standardized in concentration of 105 cells/mL. Four copper plates and four stainless steel plates were completely immersed for one minute in bacteria and fungi/yeasts solutions and left to dry for a day at room temperature. Subsequently, samples were collected from the metal plates with the aid of sterile swab and delimiter. These samples were planted onto Plate Count Agar (for mesophilic culture) and Sabouraud Dextrose Agar (for fungi and yeast culture) and incubated at 36°C for 48 hours and at 25°C for 5-7 days, respectively. After incubation, the colonies recovered from the plates were counted according to IN 62 of the Brazilian Ministry of Agriculture. Almost all contamination was eliminated from the surface of copper plates in a single day, while the stainless steel plates proved to be innocuous to the screened microorganisms. Copper, as a contact surface, proved to have important antimicrobial action on bacteria, fungi and yeasts common to hatcheries.

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RESUMO

Since 2008, when the US Environmental Protection Agency (EPA) registered copper and its alloys as an antimicrobial agent for contact surfaces, research has demonstrated their antimicrobial activity. The aim of this study was to evaluate the efficacy of antimicrobial copper against bacteria and fungi isolated from commercial poultry hatcheries in order to develop a microbiological control alternative in these environments. Samples were collected from the surfaces of hatcher baskets from two hatcheries. Mesophilic microorganisms and fungi/yeasts were isolated and standardized in concentration of 105 cells/mL. Four copper plates and four stainless steel plates were completely immersed for one minute in bacteria and fungi/yeasts solutions and left to dry for a day at room temperature. Subsequently, samples were collected from the metal plates with the aid of sterile swab and delimiter. These samples were planted onto Plate Count Agar (for mesophilic culture) and Sabouraud Dextrose Agar (for fungi and yeast culture) and incubated at 36°C for 48 hours and at 25°C for 5-7 days, respectively. After incubation, the colonies recovered from the plates were counted according to IN 62 of the Brazilian Ministry of Agriculture. Almost all contamination was eliminated from the surface of copper plates in a single day, while the stainless steel plates proved to be innocuous to the screened microorganisms. Copper, as a contact surface, proved to have important antimicrobial action on bacteria, fungi and yeasts common to hatcheries.(AU)

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A piometra é uma infecção aguda ou crônica do útero que ocorre frequentemente em cadelas não castradas, podendo também ocorrer em gatas domésticas e selvagens, sendo poucos os estudos relacionados à piometra em grandes felídeos. O objetivo deste relato foi descrever um caso de piometra em uma leoa (Panthera leo) de cativeiro, as lesões de necropsia e histológicas, bem como os resultados da análise microbiológica. Uma leoa com aproximadamente 23 anos, pertencente a um criadouro conservacionista de Santa Maria-RS, foi encontrada morta pela manhã em seu recinto. Após coleta de dados, procedeu-se à necropsia e à coleta de material para análise histopatológica e bacteriológica. A análise microbiológica revelou predomínio das bactérias Streptococcus sp. e Escherichia coli no conteúdo purulento do útero, caracterizando como piometra, e a bactéria predominante em plasma, fígado e medula óssea foi E. coli. De acordo com o laudo histopatológico, as alterações observadas nessa leoa sugerem um quadro de septicemia grave, sendo a origem do foco infeccioso bacteriano, provavelmente, a piometra. Considera-se importante chamar a atenção dos médicos veterinários de animais selvagens para um diagnóstico precoce dessa doença, que é comum em cadelas, mas que pode acometer também felídeos selvagens e levá-los à morte.

Pyometra is an acute or chronic uterus infection that occurs often in not spayed dogs, but may also occur in wild and domestic cats, and there are few studies related to pyometra in big cats. The aim of this report was to describe a case of pyometra in a lion (Panthera leo) in captivity, the gross and microscopic lesions found at necropsy, and the results of the microbiological analysis. A female with approximately 23 years of age, belonging to a Conservationist Breeding Center located in Santa Maria-RS-Brazil was found dead in her enclosure in the morning. After data collection, we proceeded to the autopsy and collection of material for histopathological and bacteriological analyzes. Microbiological analysis revealed a predominance of the bacteria Streptococcus sp and Escherichia coli in the uterus content, characterized as pyometra and the predominant bacterium in the plasma, liver and bone marrow was Escherichia coli. According to histopathology, the changes observed in this lioness suggest a framework of severe septicemia, being the source of the bacterial infection, probably, pyometra. It is considered important to draw the attention of zoo and wildlife veterinarians for an early diagnosis of this common disease in dogs, which can also affect large wild cats and lead them to death.

Assuntos

RESUMO

A piometra é uma infecção aguda ou crônica do útero que ocorre frequentemente em cadelas não castradas, podendo também ocorrer em gatas domésticas e selvagens, sendo poucos os estudos relacionados à piometra em grandes felídeos. O objetivo deste relato foi descrever um caso de piometra em uma leoa (Panthera leo) de cativeiro, as lesões de necropsia e histológicas, bem como os resultados da análise microbiológica. Uma leoa com aproximadamente 23 anos, pertencente a um criadouro conservacionista de Santa Maria-RS, foi encontrada morta pela manhã em seu recinto. Após coleta de dados, procedeu-se à necropsia e à coleta de material para análise histopatológica e bacteriológica. A análise microbiológica revelou predomínio das bactérias Streptococcus sp. e Escherichia coli no conteúdo purulento do útero, caracterizando como piometra, e a bactéria predominante em plasma, fígado e medula óssea foi E. coli. De acordo com o laudo histopatológico, as alterações observadas nessa leoa sugerem um quadro de septicemia grave, sendo a origem do foco infeccioso bacteriano, provavelmente, a piometra. Considera-se importante chamar a atenção dos médicos veterinários de animais selvagens para um diagnóstico precoce dessa doença, que é comum em cadelas, mas que pode acometer também felídeos selvagens e levá-los à morte(AU)

Pyometra is an acute or chronic uterus infection that occurs often in not spayed dogs, but may also occur in wild and domestic cats, and there are few studies related to pyometra in big cats. The aim of this report was to describe a case of pyometra in a lion (Panthera leo) in captivity, the gross and microscopic lesions found at necropsy, and the results of the microbiological analysis. A female with approximately 23 years of age, belonging to a Conservationist Breeding Center located in Santa Maria-RS-Brazil was found dead in her enclosure in the morning. After data collection, we proceeded to the autopsy and collection of material for histopathological and bacteriological analyzes. Microbiological analysis revealed a predominance of the bacteria Streptococcus sp and Escherichia coli in the uterus content, characterized as pyometra and the predominant bacterium in the plasma, liver and bone marrow was Escherichia coli. According to histopathology, the changes observed in this lioness suggest a framework of severe septicemia, being the source of the bacterial infection, probably, pyometra. It is considered important to draw the attention of zoo and wildlife veterinarians for an early diagnosis of this common disease in dogs, which can also affect large wild cats and lead them to death(AU)

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RESUMO

Rhodococcus equi é o agente etiológico da rodococose equina, importante doença respiratória de potros. Especialmente na última década, a emergência de cepas resistentes aos antimicrobianos empregados no tratamento da rodococose tem sido relatada. Nesse sentido, há a necessidade de estudos envolvendo terapias alternativas e novas tecnologias, incluindo o uso de plantas medicinais e nanotecnologia. Neste trabalho utilizou-se Melaleuca alternifolia nas seguintes formulações: óleo livre, nanocápsula, nanoemulsão e a combinação de óleo livre com nanocápsula e com nanoemulsão, além do seu composto majoritário, terpinen-4-ol, a fim de verificar a atividade antimicrobiana frente a isolados de R. equi de diferentes origens. Utilizou-se o método de microdiluição em caldo na determinação das concentrações inibitória mínima (CIM) e bactericida mínima (CBM) das diferentes formulações frente aos isolados (n=24). Verificou-se baixo potencial para atividade antibacteriana de M. alternifolia na formulação de óleo livre. Todavia, essa atividade foi potencializada quando se incorporou o óleo essencial às nanoformulações. O composto terpinen-4-ol demonstrou potencial atividade antibacteriana quando incorporado ao óleo essencial e quando utilizado isoladamente. Verificou-se que tanto M. alternifolia quanto terpinen-4-ol testados possuem atividade antimicrobiana contra isolados de R. equi, sugerindo seu emprego em estudos avaliando seu potencial para o tratamento da rodococose.

Rhodococcus equi causes rodococose in horses, characterized by bronchopneumonia in foals. Due to reports of antimicrobial resistance, it is important to develop studies involving alternative therapies and new technologies, including the use of medicinal plants and nanotechnology. In this work, the plant Melaleuca alternifolia in oil free formulations, nanocapsule, nanoemulsion and the combination of free and nanocapsule oil nanoemulsion, besides its major compound, terpinen-4-ol, were used in order to verify antimicrobial activity against isolates of R. equi. The broth microdilution method was employed to determine the minimum inhibitory (MIC) and minimum bactericidal (MBC) concentrations of different formulations against 24 isolates. There was low antibacterial activity of M. alternifolia in oil free formulation; however, it was observed that the activity was enhanced when incorporated as essential oil the nanoformulations. The major compound, terpinen-4-ol, showed bactericidal and bacteriostatic activity when used alone. It is suggested that M. alternifolia, in association with nanocarriers systems, as well as terpinen -4-ol, presents potential for future studies concerning the equine rodococosis therapy.

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