56 research outputs found
Evolution and biogeography of fire-eye antbirds (genus Pyriglena): Insights from molecules and songs
The importance of climatic and geologic factors as drivers of population differentiation and speciation in the Neotropical region has long been appreciated. However, many questions remain regarding their roles underlying the processes and patterns of diversification. Studies conducted in distinct regions containing a suite of geological and ecological conditions constitute ideal scenarios to assess the role of Pleistocene climatic changes, rivers, and mountain building as historical diversification mechanisms. In chapters 1 and 2, I used an integrative approach combining molecular phylogenetics, phylogeography and population genetics to elucidate the importance of climatic and geological factors as engines of diversification. I focused on the South American fire-eye antbirds (genus Pyriglena), which occur in forested areas in southeastern Amazonian basin, Pantanal basin, Andes and Atlantic Coast. My study suggests that fire-eyes represent a young and rapid diversification in South America. It is conceivable that the origin of the major clades in this group trace back to the formation of the modern course of large rivers in the Amazonian basin and Atlantic Forest, with subsequent diversification fostered by more recent Pleistocene climatic oscillations creating opportunities for range expansion and geographic isolation in the Andes, Pantanal and Atlantic Forest. However, the role of large rivers as historical barriers to dispersal was apparently stronger in the Amazon basin relative to western South America (western lowlands and Andes) and Atlantic Forest. On the other hand, climatic oscillations seemed less important in creating opportunities for geographic differentiation within the Amazon comparative to the other regions. Fire-eyes seemed to have a complex history of diversification, involving large-scale geological and climatic processes acting over regional and continental scales during the last ~ 2.5 Mya. In chapter 3, I examined in detail how songs varied across the range of Atlantic Forest fire-eye antbirds, and I tested several different hypotheses of the origin of song divergence in an attempt to explain their current vocal variation. Genetic differentiation and introgressive hybridization seemed to explain the overall song variation and geographic structuring in fire-eyes better than alternative factors such as body size, bill morphology and ecology
The invasive species rules: competitive exclusion in forest avian mixed-species flocks in a fragmented landscape
Evidence of checkerboard patterns of species' distribution in avian mixed-species flocks suggest that competition is one of the forces shaping the composition and structure of these associations. However, evidence of competition among flock species comes from studies performed in well-preserved regions and no study has reported the interactions between invasive and native flocking species in human-modified landscapes. Such studies are important because evidence show that avian social systems such as mixed-species flocks suffer several negative impacts of habitat fragmentation. In this study, it is shown that an invasive woodcreeper (Lepidocolaptes angustirostris) from open areas of central and western South America is: 1) expanding its range into that of a native Atlantic Forest woodcreeper (L. squamatus)2) using the same forest fragments in which the native woodcreeper occurs3) regularly joining Atlantic Forest mixed-species flocks that contain the native woodcreeper4) overlapping in foraging height with the native woodcreeper during flockingand 5) engaging in aggressive encounters and excluding the native woodcreeper from flocks. We suggest that this aggressive behavior is a consequence of the overlap in foraging height between the invasive and native species in their original habitats and that their contact has so recently been established. This study suggests that competitive interactions mediated by aggressive behaviors of invasive species may have a negative impact on the fitness of native mixed-species flock species in a fragmented landscape.Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)Graduate Program in Ecology and Evolution from Federal University of Sao Paulo (UNIFESP-Diadema)Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)Biota ProgramNational Science FoundationWorld Wildlife Fund (WWF)Graduate Program of Ecology, Conservation and Wildlife Management (ECMVS) from Federal University of Minas Gerais (UFMG)CNPqPrograma Natureza e Sociedade WWF/SUNY projetoUniv Fed Sao Paulo, Dept Ecol & Biol Evolut, BR-09972270 Diadema, SP, BrazilUniv Brasilia, Inst Ciencias Biol, Dept Zool, BR-70910900 Brasilia, DF, BrazilUniv Fed Vicosa, Dept Biol Anim, Museu Zool Joao Moojen de Oliveira, BR-36570000 Vicosa, MG, BrazilUniv Fed Sao Paulo, Dept Ecol & Biol Evolut, BR-09972270 Diadema, SP, BrazilBiota Program: 2010/05445-2Biota Program: 2015/18287-0Biota Program: 2011/50143-7Biota Program: 2011/23155-4Biota Program: 2013/50297-0National Science Foundation: DOB 1343578Programa Natureza e Sociedade WWF/SUNY projeto: CSR 142-00Web of Scienc
Antimicrobial resistance in bacteria isolated from pigs with respiratory clinical signs in Brazil
A resistência antimicrobiana é uma questão atual e muito importante para a saúde pública, geralmente associada ao uso indiscriminado de antimicrobianos na produção animal. Diante disso, foi investigado o perfil de sensibilidade-antimicrobiana em isolados bacterianos de suínos com sinais clínicos respiratórios no Brasil. Foram estudadas 96 isolados provenientes de 51 granjas de suínos do Brasil. O método de disco-difusão foi empregado usando 14 antimicrobianos: amoxicilina, penicilina, ceftiofur, ciprofloxacina, enrofloxacina, clortetraciclina, doxiciclina, oxitetraciclina, tetraciclina, eritromicina, tilmicosina, florfenicol,lincomicina e sulfadiazina/trimetoprim. Streptococcus suis e Bordetella bronchiseptica foram os patógenos que apresentaram maiores níveis de resistência. Haemophilus parasuis apresentou altos níveis de resistência à sulfadiazina/trimetoprim (9/18=50%). Observou-se que isolados das regiões Centro-Oeste e Sul apresentaram quatro vezes mais chance de serem multirresistentes do que os isolados da região Sudeste. A maioria foi resistente a pelo menos um agente antimicrobiano (98,75%; 158/160) e 31,25% (50/160) das estirpes isoladas eram multirresistentes. No geral, os resultados do presente estudo mostraram grande nívelde resistência à lincomicina, eritromicina, sulfadiazina/trimetoprim e tetraciclina entre patógenos respiratórios bacterianos isolados de suínos no Brasil. Os altos níveis de resistência antimicrobiana em patógenos bacterianos respiratórios em suínos reforçam a necessidade do uso criterioso de antimicrobianos na suinocultura brasileira.Antimicrobial resistance is a current and important issue to public health, and it is usually associated with the indiscriminate use of antimicrobials in animal production. This study aimed to evaluate the antimicrobial susceptibility profile in bacterial isolates from pigs with clinical respiratory signs in Brazil. One hundred sixty bacterial strains isolated from pigs from 51 pig farms in Brazil were studied. In vitro disk-diffusion method was employed using 14 antimicrobial agents: amoxicillin, penicillin, ceftiofur, ciprofloxacin, enrofloxacin, chlortetracycline, doxycycline, oxytetracycline, tetracycline, erythromycin, tilmicosin, florfenicol, lincomycin, and sulfadiazine/trimethoprim. The majority of isolates were resistant to at least one antimicrobial agent (98.75%; 158/160), while 31.25% (50/160) of the strains were multidrug resistant. Streptococcus suis and Bordetella bronchiseptica were the pathogens that showed higher resistance levels. Haemophilus parasuis showed high resistance levels to sulfadiazine/trimethoprim (9/18=50%). We observed that isolates from the midwestern and southern regions exhibited four times greater chance of being multidrug resistant than the isolates from the southeastern region studied. Overall, the results of the present study showed a great level of resistance to lincomycin, erythromycin, sulfadiazine/trimethoprim, and tetracycline among bacterial respiratory pathogens isolated from pigs in Brazil. The high levels of antimicrobial resistance in swine respiratory bacterial pathogens highlight the need for the proper use of antimicrobials in Brazilian pig farms
Assessment of the experimental infection by Echinostoma paraensei (Lie & Basch, 1967) (Trematoda: Echinostomatidae) in two Biomphalaria tenagophila (D’Orbigny, 1835) (Gastropoda: Planorbidae) isolates resistant and susceptible to Schistosoma mansoni (Sambon, 1907) (Trematoda: Schistosomatidae)
Different isolates of Biomphalaria tenagophila show a large spectrum of compatibility to the trematode Schistosoma mansoni, ranging from entirely refractory to highly susceptible. The aim of this study was to verify the pattern of compatibility of two B. tenagophila geographical isolates, resistant and susceptible to S. mansoni, when infected with Echinostoma paraensei. The snails were exposed to different numbers of miracidia, and mortality, histopathological characteristics and the number of cercariae released were evaluated. A correlation between the number of miracidia and the infectivity rate of B. tenagophila (TAIM) was observed. There was no correlation between the number of miracidia used and the number of cercariae released for both B. tenagophila isolates. Biomphalaria tenagophila (SJC) showed little susceptibility to the E. paraensei infection. The results demonstrate different degrees of compatibility for the two B. tenagophila isolates when infected with E. paraensei, and may contribute to studies about host-parasite relationships
Aves da Chapada dos Guimarães, Mato Grosso, Brasil: uma síntese histórica do conhecimento
Here we present a historical review of all known ornithological surveys carried out at Chapada dos Guimarães, central-western Brazil. We characterize the avifauna of the region following a critical review of all bird species listed by several generations of ornithologists. The final species account was produced based on extensive literature and museum consultation and on recent field work. Special attention is given to the series of papers by J.A. Allen, which was based on the monumental collecting work by H.H. Smith and his wife on the 19th century. The study area is predominantly characterized by a Cerrado bird assemblage and in a lesser extent, by Amazonian elements. A total of 393 bird species have confident records for the region. Other 52 species were cited for the region, but were judged unlikely to occur in the study area under our stringent criteria. Twenty four species collected by the Smiths are no longer recorded in the region. Six of these species are sensitive grassland specialists, and three are popular cagebirds. These species are probably extinct in the area. Seven species are waterbirds and two are Amazonian species, all of them have probably always been very rare in the region due to the lack of apropriate habitat. Six species are naturally rare, and could be overlooked. We report the first documented record of Caprimulgus longirostris for Mato Grosso and the second record of Pipraeidea melanonota for the state. We also comment on several apparently rare species on the region such as Ictinia mississipensis, Buteo melanoleucus, Harpia harpyja, Megascops usta, Asio flammeus, Berlepschia rikeri, Euscarthmus rufomarginatus, Xenopsaris albinucha, and Poospiza cinerea.É apresentada uma revisão histórica dos inventários ornitológicos conduzidos na Chapada dos Guimarães, centro-oeste do Brasil. A avifauna da região é caracterizada a partir de uma revisão crítica de todas as listas de espécies produzidas por várias gerações de ornitólogos, espécimes depositados em museus e meticulosos trabalhos de campo. Especial atenção foi dada às publicações de J.A. Allen, baseadas na monumental coleção preparada por H.H. Smith e sua esposa no final do século XIX. A avifauna da região é típica do Cerrado, abrigando também espécies amazônicas. Um total de 393 espécies de aves é listado para a região, sendo outras 52 espécies citadas pela literatura consideradas de ocorrência improvável baseado nos critérios restritivos adotados. Vinte e quatro espécies coletadas pelos Smith não foram mais registradas para a região. Seis destas espécies são campestres e bastante sensíveis a alterações antrópicas, enquanto que outras três são perseguidas pelo comércio ilegal de aves. Estas espécies provavelmente se encontram extintas na região. Sete outras espécies associadas a corpos hídricos, e duas de distribuição predominantemente Amazônica, eram provavelmente raras na região, mesmo em tempos históricos, principalmente devido à falta de hábitat adequado. Seis outras são normalmente raras, podendo ter passado despercebidas. São apresentados o primeiro registro documentado de Caprimulgus longirostris para o Mato Grosso e o segundo registro de Pipraeidea melanonota para o estado. Também são discutidos os registros de outras espécies raras na região, tais como Ictinia mississipensis, Buteo melanoleucus, Harpia harpyja, Megascops usta, Asio flammeus, Berlepschia rikeri, Euscarthmus rufomarginatus, Xenopsaris albinucha e Poospiza cinerea
The effect of early infection with Echinostoma paraensei on the interaction of Schistosoma mansoni with Biomphalaria glabrata and Biomphalaria tenagophila
Elective cancer surgery in COVID-19-free surgical pathways during the SARS-CoV-2 pandemic: An international, multicenter, comparative cohort study
PURPOSE As cancer surgery restarts after the first COVID-19 wave, health care providers urgently require data to determine where elective surgery is best performed. This study aimed to determine whether COVID-19–free surgical pathways were associated with lower postoperative pulmonary complication rates compared with hospitals with no defined pathway. PATIENTS AND METHODS This international, multicenter cohort study included patients who underwent elective surgery for 10 solid cancer types without preoperative suspicion of SARS-CoV-2. Participating hospitals included patients from local emergence of SARS-CoV-2 until April 19, 2020. At the time of surgery, hospitals were defined as having a COVID-19–free surgical pathway (complete segregation of the operating theater, critical care, and inpatient ward areas) or no defined pathway (incomplete or no segregation, areas shared with patients with COVID-19). The primary outcome was 30-day postoperative pulmonary complications (pneumonia, acute respiratory distress syndrome, unexpected ventilation). RESULTS Of 9,171 patients from 447 hospitals in 55 countries, 2,481 were operated on in COVID-19–free surgical pathways. Patients who underwent surgery within COVID-19–free surgical pathways were younger with fewer comorbidities than those in hospitals with no defined pathway but with similar proportions of major surgery. After adjustment, pulmonary complication rates were lower with COVID-19–free surgical pathways (2.2% v 4.9%; adjusted odds ratio [aOR], 0.62; 95% CI, 0.44 to 0.86). This was consistent in sensitivity analyses for low-risk patients (American Society of Anesthesiologists grade 1/2), propensity score–matched models, and patients with negative SARS-CoV-2 preoperative tests. The postoperative SARS-CoV-2 infection rate was also lower in COVID-19–free surgical pathways (2.1% v 3.6%; aOR, 0.53; 95% CI, 0.36 to 0.76). CONCLUSION Within available resources, dedicated COVID-19–free surgical pathways should be established to provide safe elective cancer surgery during current and before future SARS-CoV-2 outbreaks
Elective Cancer Surgery in COVID-19-Free Surgical Pathways During the SARS-CoV-2 Pandemic: An International, Multicenter, Comparative Cohort Study.
PURPOSE: As cancer surgery restarts after the first COVID-19 wave, health care providers urgently require data to determine where elective surgery is best performed. This study aimed to determine whether COVID-19-free surgical pathways were associated with lower postoperative pulmonary complication rates compared with hospitals with no defined pathway. PATIENTS AND METHODS: This international, multicenter cohort study included patients who underwent elective surgery for 10 solid cancer types without preoperative suspicion of SARS-CoV-2. Participating hospitals included patients from local emergence of SARS-CoV-2 until April 19, 2020. At the time of surgery, hospitals were defined as having a COVID-19-free surgical pathway (complete segregation of the operating theater, critical care, and inpatient ward areas) or no defined pathway (incomplete or no segregation, areas shared with patients with COVID-19). The primary outcome was 30-day postoperative pulmonary complications (pneumonia, acute respiratory distress syndrome, unexpected ventilation). RESULTS: Of 9,171 patients from 447 hospitals in 55 countries, 2,481 were operated on in COVID-19-free surgical pathways. Patients who underwent surgery within COVID-19-free surgical pathways were younger with fewer comorbidities than those in hospitals with no defined pathway but with similar proportions of major surgery. After adjustment, pulmonary complication rates were lower with COVID-19-free surgical pathways (2.2% v 4.9%; adjusted odds ratio [aOR], 0.62; 95% CI, 0.44 to 0.86). This was consistent in sensitivity analyses for low-risk patients (American Society of Anesthesiologists grade 1/2), propensity score-matched models, and patients with negative SARS-CoV-2 preoperative tests. The postoperative SARS-CoV-2 infection rate was also lower in COVID-19-free surgical pathways (2.1% v 3.6%; aOR, 0.53; 95% CI, 0.36 to 0.76). CONCLUSION: Within available resources, dedicated COVID-19-free surgical pathways should be established to provide safe elective cancer surgery during current and before future SARS-CoV-2 outbreaks
Climatic oscillations shape the phylogeographical structure of Atlantic Forest fire-eye antbirds (Aves: Thamnophilidae)
In the present study, mitochondrial (mt)DNA sequence data were used to examine the genetic structure of fire-eye antbirds (genus Pyriglena) along the Atlantic Forest and the predictions derived from the river hypothesis and from a Last Glacial Maximum Pleistocene refuge paleomodel were compared to explain the patterns of genetic variation observed in these populations. A total of 266 individuals from 45 populations were sampled over a latitudinal transect and a number of phylogeographical and population genetics analytical approaches were employed to address these questions. The pattern of mtDNA variation observed in fire-eye antbirds provides little support for the view that populations were isolated by the modern course of major Atlantic Forest rivers. Instead, the data provide stronger support for the predictions of the refuge model. These results add to the mounting evidence that climatic oscillations appear to have played a substantial role in shaping the phylogeographical structure and possibly the diversification of many taxa in this region. However, the results also illustrate the potential for more complex climatic history and historical changes in the geographical distribution of Atlantic Forest than envisioned by the refuge model. (c) 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 105, 900824.CNPq (Brazil)CNPq-BrazilUS National Science Foundation [OISE-0555482]US National Science FoundationWhitney R. Harris World Ecology Center at University of Missouri St Louis, University of Missouri St Louis Department of BiologyWhitney R. Harris World Ecology Center at University of Missouri - St Louis, University of Missouri - St Louis Department of BiologyAmerican Museum of Natural HistoryAmerican Museum of Natural HistorySt Louis Audubon SocietySt Louis Audubon SocietySigma XiSigma X
The Black-goggled Tanager (trichothraupis Melanops): An Occasional Kleptoparasite in Mixed-species Bird Flocks and Ant Swarms of Southeastern Brazil
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