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1.
Rev. biol. trop ; 72(1): e53860, ene.-dic. 2024. graf
Article in English | LILACS, SaludCR | ID: biblio-1559318

ABSTRACT

Abstract Introduction: Leptodactylus latinasus and Physalaemus cuqui are sympatric anuran species with similar environmental requirements and contrasting reproductive modes. Climatic configuration determines distribution patterns and promotes sympatry of environmental niches, but specificity/selectivity determines the success of reproductive modes. Species distribution models (SDM) are a valuable tool to predict spatio-temporal distributions based on the extrapolation of environmental predictors. Objectives: To determine the spatio-temporal distribution of environmental niches and assess whether the protected areas of the World Database of Protected Areas (WDPA) allow the conservation of these species in the current scenario and future. Methods: We applied different algorithms to predict the distribution and spatio-temporal overlap of environmental niches of L. latinasus and P. cuqui within South America in the last glacial maximum (LGM), middle-Holocene, current and future scenarios. We assess the conservation status of both species with the WDPA conservation units. Results: All applied algorithms showed high performance for both species (TSS = 0.87, AUC = 0.95). The L. latinasus predictions showed wide environmental niches from LGM to the current scenario (49 % stable niches, 37 % gained niches, and 13 % lost niches), suggesting historical fidelity to stable climatic-environmental regions. In the current-future transition, L. latinasus would increase the number of stable (70 %) and lost (20 %) niches, suggesting fidelity to lowland regions and a possible trend toward microendemism. P. cuqui loses environmental niches from the LGM to the current scenario (25 %) and in the current-future transition (63 %), increasing the environmental sympathy between both species; 31 % spatial overlap in the current scenario and 70 % in the future. Conclusion: Extreme drought events and rainfall variations, derived from climate change, suggest the loss of environmental niches for these species that are not currently threatened but are not adequately protected by conservation units. The loss of environmental niches increases spatial sympatry which represents a new challenge for anurans and the conservation of their populations.


Resumen Introducción: Leptodactylus latinasus y Physalaemus cuqui son especies de anuros simpátricos con requerimientos ambientales similares y modos reproductivos contrastantes. La configuración climática determina los patrones de distribución y promueve la simpatría de los nichos ambientales, pero la especificidad/selectividad determina el éxito de los modos reproductivos. Los modelos de distribución de especies (MDE) son una herramienta valiosa para predecir distribuciones espacio-temporales basadas en la extrapolación de predictores ambientales. Objetivos: Determinar la distribución espacio-temporal de los nichos ambientales y evaluar si las áreas protegidas de la base de Datos Mundial de Áreas Protegidas (DMAP) permiten la conservación de estas especies en el escenario actual y futuro. Métodos: Aplicamos diferentes algoritmos para predecir la distribución y superposición espacio-temporal de nichos ambientales de L. latinasus y P. cuqui dentro de América del Sur en el último máximo glacial (UGM), Holoceno medio, actual y futuro. Evaluamos el estado de conservación de ambas especies con las unidades de conservación de la DMAP. Resultados: Todos los algoritmos aplicados mostraron un alto rendimiento para ambas especies (TSS = 0.87, AUC = 0.95). Las predicciones de L. latinasus mostraron amplios nichos ambientales desde LGM hasta el escenario actual (49 % de nichos estables, 37 % de nichos ganados y 13 % de nichos perdidos), sugiriendo fidelidad histórica por regiones climático-ambientales estables. En la transición actual-futura L. latinasus incrementaría la cantidad de nichos estables (70 %) y perdidos (20 %), sugiriendo fidelidad por regiones de tierras bajas y la posible tendencia hacia el microendemismo. P. cuqui pierde nichos ambientales desde el LGM al escenario actual (25 %) y en la transición actual-futura (63 %), incrementando la simpatría ambiental entre ambas especies; 31 % de superposición espacial en el escenario actual y 70 % en el futuro. Conclusión: Los eventos de sequía extrema y las variaciones de precipitaciones, derivados del cambio climático, sugieren la pérdida de nichos ambientales para estas especies, actualmente no se encuentran amenazadas, pero no están adecuadamente protegidas por las unidades de conservación. La pérdida de nichos ambientales aumenta la simpatría espacial que representa un nuevo desafío para estos anuros y la conservación de sus poblaciones.


Subject(s)
Animals , Anura/classification , Spatio-Temporal Analysis , South America , Climate Change
2.
Mar Pollut Bull ; 207: 116916, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39236490

ABSTRACT

The coastal areas of Montevideo-Canelones, Uruguay, are strongly affected by anthropogenic activities. Polycyclic aromatic hydrocarbons (PAHs) are of especial ecological concern due to their acute toxicity. The study aimed to evaluate the relationship between different pollution levels and the ecological structure of macrobenthic communities of the subtidal coastal zone and to assess the ecological risk of the 16 PAHs identified by US EPA for these communities. Communities in Montevideo Bay are under the influence of combined effects of natural oscillations and anthropic pollution, while the adjacent coastal areas communities are strongly influenced by El Niño Southern Oscillation. Toxicity assessments classified two sites in Montevideo Bay as medium to low risk. This study allowed recognizing the complex nature of the responses of benthic organisms to multiple stressors and the importance of considering different approaches.


Subject(s)
Environmental Monitoring , Estuaries , Polycyclic Aromatic Hydrocarbons , Water Pollutants, Chemical , Polycyclic Aromatic Hydrocarbons/analysis , Polycyclic Aromatic Hydrocarbons/toxicity , Water Pollutants, Chemical/analysis , Water Pollutants, Chemical/toxicity , Animals , Petroleum/toxicity , Uruguay , Aquatic Organisms/drug effects , Petroleum Pollution , Invertebrates/drug effects , South America
3.
Sci Adv ; 10(36): eadn1466, 2024 Sep 06.
Article in English | MEDLINE | ID: mdl-39231236

ABSTRACT

Scientific research has suggested that maize spread from Mexico and arrived in lowland South America in a state of partial domestication. However, archaeological samples with primitive morphological characteristics that corroborate this finding have not been recorded in the region thus far. Unexpectedly, many samples were identified in the Peruaçu Valley with characteristics never previously observed in South America. These archaeological samples with primitive characteristics, which are the focus of this work, represent the furthest records from the center of origin of the species and the longest duration of the maintenance of such characteristics (between 1010 and 570 years before present). The findings of this study, including archaeological samples, native races, and samples of teosinte, attest to a long history of maize diversification in lowland South America.


Subject(s)
Archaeology , Zea mays , South America , Mexico , Domestication
4.
Syst Parasitol ; 101(5): 59, 2024 Aug 24.
Article in English | MEDLINE | ID: mdl-39180679

ABSTRACT

In 1937, Travassos described a new species of nematode in the genus Longistriata Schulz, 1926. He referred to it seven times as L. zetta in the main text, but also five times as L. zeta in the figure legends. This nominal species is currently assigned to the genus Guerrerostrongylus Sutton and Durette-Desset, 1991. The complete bibliography referring to this species from 1937 to date comprises only 22 works. Although the spelling 'zetta' has prevailed since 2011, the correct original spelling of its specific name remains unsettled. Acting as First Revisers under Articles 24.2.3 and 32.2.1 of the International Code of Zoological Nomenclature, we hereby choose 'zeta' as the correct original spelling of the specific name of this nematode, thus rendering 'zetta' an unavailable incorrect spelling. In making this choice, we have taken into account Travassos' obvious intention to name the species after the sixth letter of the Greek alphabet and the longer use of the spelling 'zeta' in the relevant literature, especially in those works in which 'zeta' (never 'zetta') was first combined with other generic names. We believe that standardizing the use of the spelling 'zeta' as the correct original spelling is the best way to stabilize this name.


Subject(s)
Terminology as Topic , Animals , Rodentia/parasitology , South America , Species Specificity , Heligmosomatoidea/classification , Heligmosomatoidea/anatomy & histology
5.
PLoS One ; 19(8): e0300830, 2024.
Article in English | MEDLINE | ID: mdl-39190628

ABSTRACT

Comparative mitogenomics and its evolutionary relationships within Bryconidae remains largely unexplored. To bridge this gap, this study assembled 15 mitogenomes from 11 Bryconidae species, including five newly sequenced. Salminus mitogenomes, exceeding 17,700 bp, exhibited the largest size, contrasting with a median size of 16,848 bp in the remaining species (Brycon and Chilobrycon). These mitogenomes encode 37 typical mitochondrial genes, including 13 protein-coding, 2 ribosomal RNA, and 22 transfer RNA genes, and exhibit the conserved gene arrangement found in most fish species. Phylogenetic relationships, based on the maximum-likelihood method, revealed that the trans-Andean species (found in northwestern South America) clustered into two main sister clades. One clade comprised the trans-Andean species from the Pacific slope, Brycon chagrensis and Chilobrycon deuterodon. The other clade grouped the trans-Andean species from the Magdalena-Cauca Basin Brycon moorei and Salminus affinis, with their respective cis-Andean congeners (found in eastern South America), with Brycon rubricauda as its sister clade. Since the current members of Brycon are split in three separated lineages, the systematic classification of Bryconidae requires further examination. This study provides novel insights into mitogenome characteristics and evolutionary pathways within Bryconidae, standing as crucial information for prospective phylogenetic and taxonomic studies, molecular ecology, and provides a valuable resource for environmental DNA applications.


Subject(s)
Characiformes , Genome, Mitochondrial , Phylogeny , Animals , Characiformes/genetics , Characiformes/classification , RNA, Transfer/genetics , RNA, Ribosomal/genetics , Evolution, Molecular , South America
6.
Cell ; 187(18): 4819-4823, 2024 Sep 05.
Article in English | MEDLINE | ID: mdl-39121858

ABSTRACT

More globally diverse perspectives are needed in genomic studies and precision medicine practices on non-Europeans. Here, we illustrate this by discussing the distribution of clinically actionable genetic variants involved in drug response in Andean highlanders and Amazonians, considering their environment, history, genetic structure, and historical biases in the perception of biological diversity of Native Americans.


Subject(s)
Genomics , Humans , Genetic Variation , Indians, South American/genetics , Genome, Human , South America , Precision Medicine
7.
Emerg Infect Dis ; 30(9): 1834-1840, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39173662

ABSTRACT

Western equine encephalitis virus (WEEV) is a mosquitoborne virus that reemerged in December 2023 in Argentina and Uruguay, causing a major outbreak. We investigated the outbreak using epidemiologic, entomological, and genomic analyses, focusing on WEEV circulation near the Argentina‒Uruguay border in Rio Grande do Sul state, Brazil. During November 2023‒April 2024, the outbreak in Argentina and Uruguay resulted in 217 human cases, 12 of which were fatal, and 2,548 equine cases. We determined cases on the basis of laboratory and clinical epidemiologic criteria. We characterized 3 fatal equine cases caused by a novel WEEV lineage identified through a nearly complete coding sequence analysis, which we propose as lineage C. Our findings highlight the importance of continued surveillance and equine vaccination to control future WEEV outbreaks in South America.


Subject(s)
Disease Outbreaks , Encephalitis Virus, Western Equine , Molecular Epidemiology , Phylogeny , Animals , Encephalitis Virus, Western Equine/genetics , Humans , Horses , Uruguay/epidemiology , South America/epidemiology , Horse Diseases/epidemiology , Horse Diseases/virology , Male , Encephalomyelitis, Western Equine/epidemiology , Encephalomyelitis, Western Equine/virology , Female , Argentina/epidemiology , Encephalomyelitis, Equine/epidemiology , Encephalomyelitis, Equine/virology , Encephalomyelitis, Equine/veterinary , Adult
8.
Microb Pathog ; 195: 106895, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39208965

ABSTRACT

Deadly outbreaks among poultry, wild birds, and carnivorous mammals by the highly pathogenic H5N1 virus of the clade 2.3.4.4b have been reported in South America. The increasing virus incidence in various mammal species poses a severe zoonotic and pandemic threat. In Uruguay, the clade 2.3.4.4b viruses were first detected in February 2023, affecting wild birds and backyard poultry. Three months after the first reported case in Uruguay, the disease affected a population of 23 coatis (Nasua) in an ecological park. Most animals became infected, likely directly or indirectly from wild birds in the park, and experienced sudden death. Five animals from the colony survived, and four of them developed antibodies. The genomes of the H5N1 strains infecting coatis belonged to the B3.2 genotype of the clade 2.3.4.4b. Genomes from coatis were closely associated with those infecting backyard poultry, but transmission likely occurred through wild birds. Notable, two genomes have a 627K substitution in the RNA polymerase PB2 subunit, a hallmark amino acid linked to mammalian adaptation. Our findings support the ability of the avian influenza virus of the 2.3.4.4b clade to infect and transmit among terrestrial mammals with high pathogenicity and undergo rapid adaptive changes. It also highlights the coatis' ability to develop immunity and naturally clear the infection.


Subject(s)
Animals, Wild , Genome, Viral , Influenza A Virus, H5N1 Subtype , Influenza in Birds , Mutation , Phylogeny , Procyonidae , Animals , Procyonidae/virology , Influenza in Birds/virology , Influenza A Virus, H5N1 Subtype/genetics , Influenza A Virus, H5N1 Subtype/pathogenicity , Influenza A Virus, H5N1 Subtype/isolation & purification , Genome, Viral/genetics , Uruguay , Animals, Wild/virology , Birds/virology , Orthomyxoviridae Infections/virology , Orthomyxoviridae Infections/veterinary , Poultry/virology , Genotype , Mammals/virology , South America , Disease Outbreaks/veterinary
9.
Arch Virol ; 169(9): 187, 2024 Aug 26.
Article in English | MEDLINE | ID: mdl-39187633

ABSTRACT

Orthohantaviruses are zoonotic pathogens that cause acute and severe syndromes in humans. This review was performed to estimate the occurrence of human orthohantaviruses in South America between 2010 and 2022. A careful evaluation of the eligibility and quality of the articles was carried out after a systematic bibliographic search of four databases. The pooled frequency of human orthohantaviruses was calculated using a random effects model meta-analysis. The heterogeneity of estimates (resulting from the chi2 test and I2 statistics) was investigated by subgroup analysis and meta-regression. 1,962 confirmed cases of orthohantavirus infections were diagnosed among 35,548 individuals from seven South American countries. The general occurrence of orthohantaviruses was estimated to be 4.4% (95% confidence interval: 2.9-6.2%) based on general pooling of human cases from 32 studies. In a subgroup analysis considering the study design and method of diagnosis, the percentages of diagnosed orthohantavirus infections differed substantially (I2 = 97.8%, p = 0.00) among South American countries. Four genetic variants of orthohantavirus have been identified circulating in Argentina, Brazil, Bolivia, Chile, Colombia, and Peru. Although laboratory diagnosis of orthohantaviruses is not performed in many countries in South America, there is evidence that four different orthohantaviruses are circulating in the region. The pooled occurrence of viral infection was approximately 4.0% in more than half of the South American countries. Updated information on the occurrence of human infections is essential for monitoring the territorial spread and determining the frequency of this zoonosis.


Subject(s)
Hantavirus Infections , Orthohantavirus , Animals , Humans , Hantavirus Infections/epidemiology , Hantavirus Infections/virology , Orthohantavirus/genetics , Orthohantavirus/classification , Orthohantavirus/isolation & purification , South America/epidemiology
10.
Anim Reprod Sci ; 268: 107571, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39111168

ABSTRACT

South American camelids (SAC) are gaining popularity for various purposes, including fiber production, trekking, and companionship. High abortion rates pose a significant health issue in SAC herds, leading to substantial economic losses for breeders. Often, the causes of these abortions remain unidentified. This review provides a comprehensive summary of the known infectious and non-infectious causes of abortions in SAC.


Subject(s)
Abortion, Veterinary , Animals , Female , Pregnancy , Abortion, Veterinary/epidemiology , Abortion, Veterinary/microbiology , Camelidae , South America/epidemiology , Camelids, New World
11.
Nat Commun ; 15(1): 5750, 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38982053

ABSTRACT

The global food system is a key driver of land-use and climate change which in turn drive biodiversity change. Developing sustainable food systems is therefore critical to reversing biodiversity loss. We use the multi-regional input-output model EXIOBASE to estimate the biodiversity impacts embedded within the global food system in 2011. Using models that capture regional variation in the sensitivity of biodiversity both to land use and climate change, we calculate the land-driven and greenhouse gas-driven footprints of food using two metrics of biodiversity: local species richness and rarity-weighted species richness. We show that the footprint of land area underestimates biodiversity impact in more species-rich regions and that our metric of rarity-weighted richness places a greater emphasis on biodiversity costs in Central and South America. We find that methane emissions are responsible for 70% of the overall greenhouse gas-driven biodiversity footprint and that, in several regions, emissions from a single year's food production are associated with global biodiversity loss equivalent to 2% or more of that region's total land-driven biodiversity loss. The measures we present are relatively simple to calculate and could be incorporated into decision-making and environmental impact assessments by governments and businesses.


Subject(s)
Biodiversity , Climate Change , Greenhouse Gases , Greenhouse Gases/analysis , Conservation of Natural Resources , Food Supply , Agriculture , South America , Methane/analysis
12.
Environ Sci Pollut Res Int ; 31(32): 44575-44607, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38954334

ABSTRACT

Residual lignocellulosic biomass (RLB) is a valuable resource that can help address environmental issues by serving as an alternative to fossil fuels and as a raw material for producing various value-added molecules. To gain a comprehensive understanding of the use of lignocellulosic waste in South America, a review was conducted over the last 4 years. The review focused on energy generation, biofuel production, obtaining platform molecules (such as ethanol, hydroxymethylfurfural, furfural, and levulinic acid), and other materials of interest. The review found that Brazil, Colombia, and Ecuador had the most RLB sources, with sugarcane, oil palm, and rice crop residues being the most prominent. In South America, RLB is used to produce biogas, syngas, hydrogen, bio-oil, biodiesel, torrefied biomass, pellets, and biomass briquettes. The most studied and produced value-added molecule was ethanol, followed by furfural, hydroxymethylfurfural, and levulinic acid. Other applications of interest that have been developed with RLB include obtaining activated carbon and nanomaterials. Significant progress has been made in South America in utilizing RLB, and some countries have been more proactive in regulating its use. However, there is still much to learn about the potential of RLB in each country. This review provides an updated perspective on the typification and valorization of residual biomass in South America and discusses the level of research and technology being applied in the region. This information can be helpful for future research on RLB in South America.


Subject(s)
Biofuels , Biomass , Lignin , Lignin/chemistry , South America
13.
PLoS Genet ; 20(7): e1011036, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38968323

ABSTRACT

Replicated clines across environmental gradients can be strong evidence of adaptation. House mice (Mus musculus domesticus) were introduced to the Americas by European colonizers and are now widely distributed from Tierra del Fuego to Alaska. Multiple aspects of climate, such as temperature, vary predictably across latitude in the Americas. Past studies of North American populations across latitudinal gradients provided evidence of environmental adaptation in traits related to body size, metabolism, and behavior and identified candidate genes using selection scans. Here, we investigate genomic signals of environmental adaptation on a second continent, South America, and ask whether there is evidence of parallel adaptation across multiple latitudinal transects in the Americas. We first identified loci across the genome showing signatures of selection related to climatic variation in mice sampled across a latitudinal transect in South America, accounting for neutral population structure. Consistent with previous results, most candidate SNPs were in putatively regulatory regions. Genes that contained the most extreme outliers relate to traits such as body weight or size, metabolism, immunity, fat, eye function, and the cardiovascular system. We then compared these results with the results of analyses of published data from two transects in North America. While most candidate genes were unique to individual transects, we found significant overlap among candidate genes identified independently in the three transects. These genes are diverse, with functions relating to metabolism, immunity, cardiac function, and circadian rhythm, among others. We also found parallel shifts in allele frequency in candidate genes across latitudinal gradients. Finally, combining data from all three transects, we identified several genes associated with variation in body weight. Overall, our results provide strong evidence of shared responses to selection and identify genes that likely underlie recent environmental adaptation in house mice across North and South America.


Subject(s)
Adaptation, Physiological , Polymorphism, Single Nucleotide , Selection, Genetic , Animals , Mice , Adaptation, Physiological/genetics , South America , Genomics/methods , Genome , Americas , Body Weight/genetics , Genetics, Population
14.
Sci Total Environ ; 948: 174752, 2024 Oct 20.
Article in English | MEDLINE | ID: mdl-39004360

ABSTRACT

Global warming has significantly altered fish distribution patterns in the ocean, shifting towards higher latitudes and deeper waters. This is particularly relevant in high-latitude marine ecosystems, where climate-driven environmental changes are occurring at higher rates than the global average. Species Distribution Models (SDMs) are increasingly being used for predicting distributional shifts in habitat suitability for marine species as a response to climate change. Here, we used SDMs to project habitat suitability changes for a range of high-latitude, pelagic and benthopelagic commercial fish species and crustaceans (10 species); from 1850 to two future climate change scenarios (SSP1-2.6: low climate forcing; and SSP5-8.5: high climate forcing). The study includes 11 Large Marine Ecosystems (LME) spanning South America, Southern Africa, Australia, and New Zealand. We identified declining and southward-shifting patterns in suitable habitat areas for most species, particularly under the SSP5-8.5 scenario and for some species such as Argentine hake (Merluccius hubbsi) in South America, or snoek (Thyrsites atun) off Southern Africa. Geographical constraints will likely result in species from Southern Africa, Australia, and New Zealand facing the most pronounced habitat losses due to rising sea surface temperatures (SST). In contrast, South American species might encounter greater opportunities for migrating southward. Additionally, the SSP5-8.5 scenario predicts that South America will be more environmentally stable compared to other regions. Overall, our findings suggest that the Patagonian shelf could serve as a climate refuge, due to higher environmental stability highlighting the importance of proactive management strategies in this area for species conservation. This study significantly contributes to fisheries and conservation management, providing valuable insights for future protection efforts in the Southern Hemisphere.


Subject(s)
Climate Change , Ecosystem , Fishes , Animals , New Zealand , South America , Australia , Fisheries , Africa, Southern , Global Warming
15.
Am Nat ; 204(2): 147-164, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39008839

ABSTRACT

AbstractPhenotypic macroevolutionary studies provide insight into how ecological processes shape biodiversity. However, the complexity of phenotype-ecology relationships underscores the importance of also validating phenotype-based ecological inference with direct evidence of resource use. Unfortunately, macroevolutionary-scale ecological studies are often hindered by the challenges of acquiring taxonomically and spatially representative ecological data for large and widely distributed clades. The South American cichlid fish tribe Geophagini represents a continentally distributed radiation whose early locomotor morphological divergence suggests habitat as one ecological correlate of diversification, but an association between locomotor traits and habitat preference has not been corroborated. Field notes accumulated over decades of collecting across South America provide firsthand environmental records that can be mined for habitat data in support of macroevolutionary ecological research. In this study, we applied a newly developed method to transform descriptive field note information into quantitative habitat data and used it to assess habitat preference and its relationship to locomotor morphology in Geophagini. Field note-derived data shed light on geophagine habitat use patterns and reinforced habitat as an ecological correlate of locomotor morphological diversity. Our work emphasizes the rich data potential of museum collections, including often-overlooked material such as field notes, for evolutionary and ecological research.


Subject(s)
Cichlids , Ecosystem , Phenotype , Animals , Cichlids/anatomy & histology , Cichlids/physiology , Locomotion , South America , Biological Evolution , Biodiversity
16.
Environ Sci Pollut Res Int ; 31(32): 45425-45440, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38965109

ABSTRACT

Ivermectin (IVM) is a widely used antiparasitic. Concerns have been raised about its environmental effects in the wetlands of Río de la Plata basin where cattle have been treated with IVM for years. This study investigated the sublethal effects of environmentally relevant IVM concentrations in sediments on the Neotropical fish Prochilodus lineatus. Juvenile P. lineatus were exposed to IVM-spiked sediments (2 and 20 µg/Kg) for 14 days, alongside a control sediment treatment without IVM. Biochemical and oxidative stress responses were assessed in brain, gills, and liver tissues, including lipid damage, glutathione levels, enzyme activities, and antioxidant competence. Muscle and brain acetylcholinesterase activity (AChE) and stable isotopes of 13C and 15N in muscle were also measured. The lowest IVM treatment resulted in an increase in brain lipid peroxidation, as measured by thiobarbituric acid reactive substances (TBARs), decreased levels of reduced glutathione (GSH) in gills and liver, increased catalase activity (CAT) in the liver, and decreased antioxidant capacity against peroxyl radicals (ACAP) in gills and liver. The highest IVM treatment significantly reduced GSH in the liver. Muscle (AChE) was decreased in both treatments. Multivariate analysis showed significant overall effects in the liver tissue, followed by gills and brain. These findings demonstrate the sublethal effects of IVM in P. lineatus, emphasizing the importance of considering sediment contamination and trophic habits in realistic exposure scenarios.


Subject(s)
Antiparasitic Agents , Ivermectin , Water Pollutants, Chemical , Animals , Ivermectin/toxicity , Antiparasitic Agents/toxicity , Water Pollutants, Chemical/toxicity , Livestock , South America , Oxidative Stress/drug effects , Geologic Sediments/chemistry , Gills/drug effects , Gills/metabolism
17.
Sci Rep ; 14(1): 17587, 2024 07 30.
Article in English | MEDLINE | ID: mdl-39080378

ABSTRACT

The distribution of a species reflects its ecological adaptability and evolutionary history, which is shaped by the environment and represents a dynamic area subject to anthropogenic environmental change. We used the MaxEnt algorithm to construct ecological niche models for four thrush species within the Turdus genus; T. amaurochalinus, T. chiguanco, T. falcklandii and T. rufiventris. These models were used to predict the potential geographic distributions of these species that are expanding their ranges in South America. Using occurrence records, we estimated currently occupied areas for each species. We also identified suitable habitats and projected possible areas to be colonized by the four species at continental scale. Temperature annual range had the highest influence for T. falcklandii, while human modification was the main variable explaining the distribution of the other three species. The potential distribution area ranged from 2.5 million km2 for T. falcklandii to nearly seven million km2 for T. amaurochalinus. Large proportions of suitable area remain unoccupied by all four species, being 50% for T. amaurochalinus and T. rufiventris, and about 70% for T. chiguanco and T. falcklandii. Anthropogenic disturbances, such as habitat loss and ecosystem transformation, lead to non-random species extinction and biotic homogenization, highlighting the importance of predictive models as valuable tools for informing mitigation policies and conservation strategies. Thrushes are progressively expanding their ranges, and the colonization of new habitats could bring new challenges.


Subject(s)
Ecosystem , South America , Animals , Conservation of Natural Resources , Songbirds/physiology , Animal Distribution
18.
Mol Phylogenet Evol ; 199: 108163, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39079596

ABSTRACT

Subterranean rodents of the genus Ctenomys (tuco-tucos) are endemic to South America and have experienced relatively recent radiation. There are about 67 recognized species that originated in approximately 1-2 MY. They stand out for their species richness, extraordinary chromosomal diversity, and wide range of habitat they occupy in the continent. Phylogenetic relationships among species of tuco-tucos have been challenging to resolve. Groups of closely-related species have been suggested, but their relationships must be resolved. This study estimates the phylogeny of the genus using massive sequencing, generating thousands of independent molecular markers obtained by RADseq, with a taxonomic sampling that includes 66% of the recognized species. The sequences obtained were mapped against the C. sociabilis genome, recovering up to 1,215 widely shared RAD loci with more than 19,000 polymorphic sites. Our new phylogenetic hypothesis corroborated the species groups previously proposed with cytochrome b gene sequences and provided a much greater resolution of the relationships among species groups. The frater group is sister to all other tuco-tucos, whereas some of the earlierliest proposals placed the sociabilis group as sister to all other tuco-tucos. Ctenomys leucodon, previously proposed as an independent lineage, is associated with the frater group with moderate statistical support. The magellanicus and mendocinus are sister groups in a major clade formed by the boliviensis, talarum, tucumanus, torquatus, and opimus groups. Ctenomys viperinus, included in the phylogeny for the first time, belongs to the tucumanus group. This multi-locus phylogenetic hypothesis provides insights into the historical biogeography of understanding this highly diverse genus.


Subject(s)
Genetic Speciation , Phylogeny , Rodentia , Animals , Rodentia/genetics , Rodentia/classification , Sequence Analysis, DNA , Genome/genetics , South America , Genomics
19.
Cien Saude Colet ; 29(7): e03792024, 2024 Jul.
Article in Spanish, English | MEDLINE | ID: mdl-38958327

ABSTRACT

We aim to conduct a comparative analysis of the implementation of PHC in nine South American countries. Three dimensions were highlighted from documentary sources: political commitment, leadership, and governance; care model; and engagement of communities and other stakeholders. The results indicate a formal commitment that places PHC at the center of efforts to achieve universal access. The following can be observed: revitalization processes in public subsystems, based on guaranteeing preventive, promotional, curative and rehabilitation actions; PHC as gatekeeper; emphasis on family and community; assigned population and territory; multidisciplinary teams; and, in some cases, the accent on interculturality expressed in the concept of "buen vivir" (good living). The PHC revitalization processes were affected by political changes. Between progress and setbacks, the segmentation of coverage was not overcome. The current moment seeks to recover more inclusive and broad public policies in the context of the return of the progressive and democratic fields. The dissemination of country experiences can contribute to the development of a comprehensive, integrated, and quality approach to PHC in the Region.


El objetivo es realizar un análisis comparativo de la implementación de la APS en nueve países de Suramérica. A partir de fuentes documentales fueron destacadas tres dimensiones: compromiso político, liderazgo y gobernanza; modelo de atención; involucramiento de comunidades y otros actores. Los resultados indican la existencia de compromiso formal que localiza la APS en el centro de los esfuerzos para lograr el acceso universal. Se observan procesos de revitalización en los subsistemas públicos, basados en la garantía de acciones preventivas, promocionales, de cura y rehabilitación; puerta de entrada; enfoque familiar y comunitario; población y territorio adscriptos; equipos multiprofesionales, y, en algunos casos, énfasis en la interculturalidad expresada en la concepción de "buen vivir". Los procesos de revitalización de la APS fueron afectados por cambios políticos. Entre avances y retrocesos, no se logró superar la segmentación de cobertura. El momento actual es de rescate de políticas públicas más inclusivas y amplias, en el contexto de recomposición de los campos progresistas y democráticos. Difundir experiencias de los países puede contribuir para el desarrollo de un enfoque de APS integral, integrada y de calidad en la Región.


Subject(s)
Health Policy , Primary Health Care , Public Policy , Primary Health Care/organization & administration , Humans , South America , Leadership , Politics , Health Services Accessibility , Delivery of Health Care/organization & administration
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