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1.
Glob Chang Biol ; 29(24): 6900-6911, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37804212

RESUMO

The global decline of terrestrial species is largely due to the degradation, loss and fragmentation of their habitats. The conversion of natural ecosystems for cropland, rangeland, forest products and human infrastructure are the primary causes of habitat deterioration. Due to the paucity of data on the past distribution of species and the scarcity of fine-scale habitat conversion maps, however, accurate assessment of the recent effects of habitat degradation, loss and fragmentation on the range of mammals has been near impossible. We aim to assess the proportions of available habitat within the lost and retained parts of mammals' distribution ranges, and to identify the drivers of habitat availability. We produced distribution maps for 475 terrestrial mammals for the range they occupied 50 years ago and compared them to current range maps. We then calculated the differences in the percentage of 'area of habitat' (habitat available to a species within its range) between the lost and retained range areas. Finally, we ran generalized linear mixed models to identify which variables were more influential in determining habitat availability in the lost and retained parts of the distribution ranges. We found that 59% of species had a lower proportion of available habitat in the lost range compared to the retained range, thus hypothesizing that habitat loss could have contributed to range declines. The most important factors negatively affecting habitat availability were the conversion of land to rangeland and high density of livestock. Significant intrinsic traits were those related to reproductive timing and output, habitat breadth and medium body size. Our findings emphasize the importance of implementing conservation strategies to mitigate the impacts caused by human activities on the habitats of mammals, and offer evidence indicating which species have the potential to reoccupy portions of their former range if other threats cease to occur.


Assuntos
Ecossistema , Gado , Animais , Humanos , Conservação dos Recursos Naturais , Mamíferos , Florestas
2.
PeerJ ; 11: e14319, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36655048

RESUMO

Ichthyomyini, a morphologically distinctive group of Neotropical cricetid rodents, lacks an integrative study of its systematics and biogeography. Since this tribe is a crucial element of the Sigmodontinae, the most speciose subfamily of the Cricetidae, we conducted a study that includes most of its recognized diversity (five genera and 19 species distributed from southern Mexico to northern Bolivia). For this report we analyzed a combined matrix composed of four molecular markers (RBP3, GHR, RAG1, Cytb) and 56 morphological traits, the latter including 15 external, 14 cranial, 19 dental, five soft-anatomical and three postcranial features. A variety of results were obtained, some of which are inconsistent with the currently accepted classification and understanding of the tribe. Ichthyomyini is retrieved as monophyletic, and it is divided into two main clades that are here recognized as subtribes: one to contain the genus Anotomys and the other composed by the remaining genera. Neusticomys (as currently recognized) was found to consist of two well supported clades, one of which corresponds to the original concept of Daptomys. Accordingly, we propose the resurrection of the latter as a valid genus to include several species from low to middle elevations and restrict Neusticomys to several highland forms. Numerous other revisions are necessary to reconcile the alpha taxonomy of ichthyomyines with our phylogenetic results, including placement of the Cajas Plateau water rat (formerly Chibchanomys orcesi) in the genus Neusticomys (sensu stricto), and the recognition of at least two new species (one in Neusticomys, one in Daptomys). Additional work is necessary to confirm other unanticipated results, such as the non-monophyletic nature of Rheomys and the presence of a possible new genus and species from Peru. Our results also suggest that ichthyomyines are one of the main Andean radiations of sigmodontine cricetids, with an evolutionary history dating to the Late Miocene and subsequent cladogenesis during the Pleistocene.


Assuntos
Arvicolinae , Sigmodontinae , Animais , Filogenia , Evolução Biológica , Peru
3.
Ecology ; 103(9): e3767, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35611451

RESUMO

Information from diversity inventories was used to study patterns of biodiversity and species distribution, to identify potential priority areas for conservation, and to guide future sampling efforts. In this context, we compiled information on non-volant small mammal communities from the high Andes (>2000 m). Here, we present an open source dataset containing information on diversity (species composition, number of individuals captured), inventory design (type of traps, sampling efforts), and environment (habitat) for both unpublished and published information. This study covers 630 mammalian communities, geographically distributed throughout the Andes in Venezuela, Colombia, Ecuador, Peru, Bolivia, Argentina, and Chile. We compiled a total of 26,412 individual records belonging to 240 species; the order with greatest number of records was Rodentia (n = 25,319, 96.06%), followed by Didelphimorphia (n = 373, 1.42%), Eulipotyphla (n = 358, 1.36%) and Paucituberculata, (n = 307, 1.16%). Andean non-volant small mammal communities harbor a range from 1 to 17 species, with 93.06% of sites being composed of one to five species, 27.78% of sites with species richness varying from 6 to 10 species, and 4.17% sites composed of more than 10 species. Multiple sampling methods were used to survey non-volant small mammals; the most representative methods were snap-traps and Sherman traps, or a combination of both, in more than 81% of the studies. This data paper represents the first large dataset of faunal species inventories for the Andes. There are no copyright restrictions associated with the use of this dataset. Please cite this data paper when its data are used total or partially in research or teaching.


Assuntos
Mamíferos , Marsupiais , Animais , Biodiversidade , Ecossistema , Humanos , Roedores
4.
Microorganisms ; 9(9)2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34576792

RESUMO

Leptospirosis is a globally distributed zoonotic disease caused by pathogenic bacteria of the genus Leptospira. This zoonotic disease affects humans, domestic animals and wild animals. Colombia is considered an endemic country for leptospirosis; Antioquia is the second department in Colombia, with the highest number of reported leptospirosis cases. Currently, many studies report bats as reservoirs of Leptospira spp. but the prevalence in these mammals is unknown. The goal of this study was to better understand the role of bats as reservoir hosts of Leptospira species and to evaluate the genetic diversity of circulating Leptospira species in Antioquia-Colombia. We captured 206 bats in the municipalities of Chigorodó (43 bats), Carepa (43 bats), Apartadó (39 bats), Turbo (40 bats), and Necoclí (41 bats) in the Urabá region (Antioquia-Colombia). Twenty bats tested positive for Leptospira spp. infection (20/206-9.70%) and the species of infected bats were Carollia perspicillata, Dermanura rava, Glossophaga soricina, Molossus molossus, Artibeus planirostris, and Uroderma convexum. These species have different feeding strategies such as frugivorous, insectivores, and nectarivores. The infecting Leptospira species identified were Leptospira borgpetersenii (3/20-15%), Leptospira alexanderi (2/20-10%), Leptospira noguchii (6/20-30%), Leptospira interrogans (3/20-15%), and Leptospira kirschneri (6/20-30%). Our results showed the importance of bats in the epidemiology, ecology, and evolution of Leptospira in this host-pathogen association. This is the first step in deciphering the role played by bats in the epidemiology of human leptospirosis in the endemic region of Urabá (Antioquia-Colombia).

5.
Am J Trop Med Hyg ; 105(4): 1013-1023, 2021 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-34370699

RESUMO

This study aimed to analyze epidemiological indicators related to seroprevalent and seroincident cases of spotted fever group rickettsiae (SFGR) and to identify housing conditions related to tick infestation. A prospective study (2016-2018) was conducted to examine rickettsial seropositivity in humans, domestic animals, and wild mammals in the municipality of Uramita, Antioquia, Colombia, where a previous Rickettsia rickettsii outbreak was reported from 2014 to 2015. The seroprevalence and its associated factors were estimated at baseline, and the seroincidence and its risk factors for humans were estimated 20 months later. A cross-sectional analysis was performed to evaluate the housing conditions linked to tick infestation. The SFGR seroprevalence was 26.70% (95% confidence interval [CI], 20.79-31.37), and the factors associated with SFGR seropositivity were male sex (adjusted prevalence ratio [PRa], 1.67; 95% CI, 1.19-2.32), age (evaluated in 5-year increments) (PRa, 1.05; 95% CI, 1.01-1.09), and household proximity (PRascattered vs. very near=3.87; 95% CI, 1.12-8.66). The overall seroincidence was 7.40% (95% CI, 4.71-11.06), and the factors associated with SFGR seroincident cases were the presence of wild animals (adjusted relative risk [RRa], 2.46; 95% CI, 1.06-4.72) and the presence of trees in the peri-domiciliary area (RRa, 0.47; 95% CI, 0.23-0.94). The prevalence of house tick infestation was 27.81% (95% CI, 21.93-34.80), and the factors associated with infestation were dirt floors (PRa, 5.88; 95% CI, 2.28-10.31), fiber cement roofs (PRa, 1.76; 95% CI, 1.07-2.83), and the presence of canines in peri-domiciliary or intra-domiciliary areas (PRa, 5.05; 95% CI, 3.31-7.19). Seropositivity rates for canines and opossums were 35.62% (26/73) and 100% (6/6), respectively. Identification of these factors will help to implement efficient surveillance programs in Colombia.


Assuntos
Infecções por Rickettsia/veterinária , Adulto , Animais , Animais Selvagens , Colômbia/epidemiologia , Cães , Feminino , Habitação , Humanos , Masculino , Pessoa de Meia-Idade , Gambás , Estudos Prospectivos , Infecções por Rickettsia/epidemiologia , Infecções por Rickettsia/microbiologia , Estudos Soroepidemiológicos , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/parasitologia , Carrapatos , Adulto Jovem
6.
J Mammal ; 100(1): 223-238, 2019 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-30846887

RESUMO

Landscape modification represents one of the most severe threats to biodiversity from local to global scales. Conversion of forest to agricultural production generally results in patches of habitat that subdivide or isolate populations, alter the behavior of species, modify interspecific interactions, reduce biodiversity, and compromise ecosystem processes. Moreover, conversion may increase exposure of humans to zoonoses to which they would otherwise rarely be exposed. We evaluated the effects of forest conversion to agriculture, and its subsequent successional dynamics, on bat communities in a region of the Amazon that was predominantly closed-canopy rainforest. Based on a nonmanipulative experiment, we quantified differences in species composition, community structure, and taxonomic biodiversity among closed-canopy forest (bosque), agricultural lands (chacra), and secondary forest (purma) for two phyllostomid guilds (frugivores and gleaning animalivores) during the wet and dry seasons. Responses were complex and guild-specific. For frugivores, species composition (species abundance distributions) differed between all possible pairs of habitats in both wet and dry seasons. For gleaning animalivores, species composition differed between all possible pairs of habitats in the dry season, but no differences characterized the wet season. Ecological structure (rank abundance distributions) differed among habitats in guild-specific and season-specific manners. For frugivores, mean diversity, evenness, and dominance were greater in bosque than in purma; mean dominance was greater in bosque than in chacra, but local rarity was greater in chacra than in bosque, and no differences were manifest between purma and chacra. For gleaning animalivores, mean diversity and evenness were greater in bosque than in purma, but no differences were manifest between chacra and bosque, or between purma and chacra. Such results have important implications for management, conservation, and the epidemiology of zoonotic diseases. La actual modificación del paisaje, a escalas que van de lo local a lo global, es una de las amenazas más severas a la biodiversidad. De manera general, la conversión de bosques a áreas agrícolas produce parches de hábitat que subdividen o aíslan poblaciones, alteran la conducta de las especies, modifican las interacciones interespecíficas, reducen la biodiversidad y comprometen las funciones de los ecosistemas. Más aún, la transformación de estos ambientes puede incrementar la probabilidad de que las poblaciones humanas interactúen con zoonosis con las que de otra manera raramente entrarían en contacto. Evaluamos los efectos de la conversión de hábitat en comunidades de murciélagos en una región de Amazonia en la que la vegetación dominante es un bosque lluvioso de copas cerradas, y en la cual los efectos de la conversión a usos agrícolas sobre la biodiversidad, y la subsecuente dinámica sucesional, son aún poco comprendidos. Por medio de un experimento no-manipulativo, cuantificamos las diferencias en composición de especies, estructura de la comunidad y diversidad taxonómica entre bosque cerrado (bosque), áreas agrícolas (chacra) y bosque secundario (purma) para dos gremios tróficos de murciélagos filostómidos (frugívoros y forrajeadores de sustrato) durante dos temporadas (secas y lluvias). Las respuestas fueron complejas y diferentes para cada gremio. Para los frugívoros, la composición de especies (distribución de las abundancias) fue diferente para todos los posibles pares de hábitats tanto para secas como para lluvias. Para los forrajeadores de sustrato, la composición de especies difirió entre todos los posibles pares de hábitats en la temporada seca, pero no en la de lluvias. La estructura ecológica (distribuciones rango-abundancia) fue también específica para gremios y temporadas. Para los frugívoros, la diversidad promedio, equidad y dominancia fueron mayores en bosque que en purma; la dominancia promedio fue mayor en bosque que en chacra, pero la rareza local fue mayor en chacra que en bosque, y no se encontraron diferencias entre purma y chacra. Para los forrajeadores de sustrato, la diversidad promedio y la dominancia fueron mayores en bosque que en purma, pero no se detectaron diferencias entre chacra y bosque, o entre purma y chacra. Estos resultados tienen importantes implicaciones para el manejo, conservación y epidemiología de zoonosis.

7.
Infect Genet Evol ; 67: 183-190, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30395997

RESUMO

Three mitochondrial regions and a fragment of a large nuclear ribosomal subunit was used to study the evolutionary patterns of An. neivai, a mosquito inhabiting mangroves and tropical forest in the lowland and coastal areas of the Yucatan Peninsula through the Pacific Ecuadorian coast. This species exhibits epidemiological importance regarding Malaria transmission in natural ecosystems, particularly in rural areas of the Pacific Colombian coast. The results based on phylogenetic networks and Bayesian inference showed no robust evidence supporting the existence of previously suggested cryptic species. Diversification patterns in geographically widespread species such as this one, are complex and therefore could impact malaria control strategies. Further studies focused on behavior, morphology, and phylogenomics will improve the understanding of the evolutionary patterns within An. neivai and its role as a disease vector.


Assuntos
Anopheles/classificação , Anopheles/genética , Genes Mitocondriais , Mitocôndrias/genética , RNA Ribossômico/genética , Animais , América Central/epidemiologia , Haplótipos , Filogenia , América do Sul/epidemiologia
8.
Methods Mol Biol ; 1604: 101-109, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28986828

RESUMO

This article will outline surveillance approaches for rodent-borne viruses (roboviruses). We present a synopsis of the main categories of trapping methods with some notes about their use in fieldwork. We also describe the types of laboratory analysis commonly used in Robovirus surveillance.


Assuntos
Zoonoses/epidemiologia , Zoonoses/virologia , Animais , Roedores
9.
Ticks Tick Borne Dis ; 8(6): 887-894, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28774495

RESUMO

Between 2006 and 2008, three outbreaks of human rickettsiosis occurred in Northwestern Colombia (municipalities of Necoclí, Los Córdobas and Turbo), with case fatality rates between 27% and 54%. The aim of this study was to determine previous exposure of wild and domestic animals to spotted fever group (SFG) rickettsiae through serological tests, to detect rickettsial evidence in their ectoparasites, and to analyze their possible role in the epidemiology of rickettsial diseases in this zone of the country. A cross-sectional association study was performed from 2010 to 2011. Blood and ectoparasite samples were collected from domestic animals and small mammals. A statistically significant association (p<0.05) between seropositive animals and the study zones was observed. A total of 2937 ticks, 672 fleas and 74 lice were collected and tested in pools by PCR. The minimum infection rate (MIR) of the positive pools was 5% in ticks, 4% in fleas, and 0% in lice. Phylogenetic analyses showed circulation of three 4.Rickettsia species: R. felis in fleas, and R. bellii and Rickettsia sp. strain Atlantic rainforest, both in Amblyomma ovale ticks. In conclusion, this study demonstrated the occurrence of SFG rickettsiae in domestic, synanthropic and wild animals, and suggests the use of equines and canines as good sentinels of infection, in the study zone. We speculate that a transmission cycle exist involving rodents in the areas where these outbreaks have occurred. Tomes' spiny rats (Proechimys semispinosus) and common opossums (Didelphis marsupialis) could be good candidates as amplifier hosts for SFG rickettsiae in enzootic/endemic zones.


Assuntos
Animais Domésticos , Animais Selvagens , Vetores Aracnídeos/microbiologia , Insetos Vetores/microbiologia , Infecções por Rickettsia/veterinária , Rickettsia/isolamento & purificação , Sifonápteros/microbiologia , Carrapatos/microbiologia , Animais , Vetores Aracnídeos/crescimento & desenvolvimento , Colômbia/epidemiologia , Estudos Transversais , Feminino , Insetos Vetores/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Larva/microbiologia , Glicoproteínas de Membrana , Ninfa/crescimento & desenvolvimento , Ninfa/microbiologia , Prevalência , Receptores de Interleucina-1 , Rickettsia/classificação , Rickettsia/genética , Infecções por Rickettsia/epidemiologia , Infecções por Rickettsia/parasitologia , Estudos Soroepidemiológicos , Sifonápteros/crescimento & desenvolvimento , Carrapatos/crescimento & desenvolvimento
10.
Ticks Tick Borne Dis ; 8(4): 477-482, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28223058

RESUMO

In February 2006, an outbreak of human rickettsiosis occurred in the municipality of Necoclí Colombia, with 35% of lethality. This episode was, followed by two more, one in the municipality of Los Cordobas in 2007 with a 54% of lethality and the other one in the municipality of Turbo in 2008 with 27% of lethality. The aim of this study was to perform serological tests in healthy persons to determine the seroprevalence of antibodies against spotted fever group (SFG) rickettsiae and develop a survey to study some infection risk-related factors. A cross-sectional study was performed in 2011 and 2012. A blood sample and survey of associated factors was performed in healthy persons. A prevalence of 32%-41% was found in healthy people. From the multivariate analysis, we found that people living more than 16 years in these sites had a 79% higher risk of being seropositive and a 46% higher risk when they reported having birds in their houses if the variable of having a horse was included in the model. In conclusion, this study shows endemicity of at least one spotted fever group Rickettsia in the study zone.


Assuntos
Doenças Endêmicas , Rickettsia/isolamento & purificação , Rickettsiose do Grupo da Febre Maculosa/epidemiologia , Adolescente , Adulto , Criança , Pré-Escolar , Colômbia/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Soroepidemiológicos , Rickettsiose do Grupo da Febre Maculosa/microbiologia , Adulto Jovem
11.
Environ Monit Assess ; 76(1): 89-104, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12125752

RESUMO

Development projects in tropical forests can impact biodiversity. Assessment and monitoring programs based on the principles of adaptive management assist managers to identify and reduce such impacts. The small mammal community is one important component of a forest ecosystem that may be impacted by development projects. In 1996, a natural gas exploration project was initiated in a Peruvian rainforest. The Smithsonian Institution's Monitoring and Assessment of Biodiversity program cooperated with Shell Prospecting and Development Peru to establish an adaptive management program to protect the region's biodiversity. In this article, we discuss the role of assessing and monitoring small mammals in relation to the natural gas project. We outline the conceptual issues involved in establishing an assessment and monitoring program, including setting objectives, evaluating the results and making appropriate decisions. We also summarize the steps taken to implement the small mammal assessment, provide results from the assessment and discuss protocols to identify appropriate species for monitoring.


Assuntos
Monitoramento Ambiental/métodos , Mamíferos/crescimento & desenvolvimento , Árvores/crescimento & desenvolvimento , Clima Tropical , Animais , Quirópteros/crescimento & desenvolvimento , Conservação dos Recursos Naturais/métodos , Conservação dos Recursos Naturais/estatística & dados numéricos , Coleta de Dados , Ecologia , Ecossistema , Monitoramento Ambiental/estatística & dados numéricos , Combustíveis Fósseis , Cooperação Internacional , Peru , Projetos de Pesquisa , Roedores/crescimento & desenvolvimento
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