Investigating the reproductive strategies of Deuterocohnia meziana (Bromeliaceae), an endangered and restricted species from South American rocky outcrops.

Studies of reproductive biology and resources availability to floral visitors by plant species are important to understand the plant-pollinator interactions that drive species adaptation. We aim to understand the relationship between reproduction mechanisms of Deuterocohnia meziana (Bromeliaceae) and pollinators. The species occurs in Bolivia and Paraguay, and it is the only species of the genus found in Brazil, where it is restricted to ironstone outcrops. These areas are currently threatened by the iron mining industry. Additionally, they face risks from fire occurrence and grazing by cattle. We analyzed the floral biology, reproductive system, phenology, and pollination ecology of a natural population of Deuterocohnia meziana, from ironstone outcrops in Brazil. The species exhibits diurnal anthesis, with stigma receptive throughout anthesis, and 77% of pollen viability. Deuterocohnia meziana produces relatively large amounts of nectar, especially early in the morning (32.8 ± 9.4 µl), with a mean sugar concentration of 23.5 (± 3.2) ºBrix. It is self-incompatible with a peak flowering occurring in August (dry season), although flowers are observed continuously throughout the year. The species exhibits two types of inflorescences, young and mature, among which an average of 13.1 and 3.6 flowers open per day, respectively. Hummingbirds and bees are the effective pollinators, although butterflies and ants also visit D. meziana flowers. The species is reliant on exogenous pollen and pollinators for fruit set. The continuous conservation of D. meziana populations and their communities is essential for preserving plant-pollinator mutualism and the floral community adapted to ironstone outcrops.

Forest type modulates mammalian responses to megafires.

Although considered an evolutionary force responsible for shaping ecosystems and biodiversity, fires' natural cycle is being altered by human activities, increasing the odds of destructive megafire events. Here, we show that forest type modulates the responses of terrestrial mammals, from species to assemblage level, to a catastrophic megafire in the Brazilian Pantanal. We unraveled that mammalian richness was higher 1 year after fire passage compared to a pre-fire condition, which can be attributed to habitat modification caused by wildfires, attracting herbivores and open-area tolerant species. We observed changes in assemblage composition between burned/unburned sites, but no difference in mammalian richness or relative abundance. However, by partitioning the effects of burned area proportion per forest type (monospecific vs. polyspecific), we detected differential responses of mammals at several levels of organization, with pronounced declines in species richness and relative abundance in monospecific forests. Eighty-six percent of the species presented moderate to strong negative effects on their relative abundance, with an overall strong negative effect for the entire assemblage. Wildfires are predicted to be more frequent with climate and land use change, and if events analogous to Pantanal-2020 become recurrent, they might trigger regional beta diversity change, benefitting open-area tolerant species.

A comparative genomics study of the microbiome and freshwater resistome in Southern Pantanal.

This study explores the resistome and bacterial diversity of two small lakes in the Southern Pantanal, one in Aquidauana sub-region, close to a farm, and one in Abobral sub-region, an environmentally preserved area. Shotgun metagenomic sequencing data from water column samples collected near and far from the floating macrophyte Eichhornia crassipes were used. The Abobral small lake exhibited the highest diversity and abundance of antibiotic resistance genes (ARGs), antibiotic resistance classes (ARGCs), phylum, and genus. RPOB2 and its resistance class, multidrug resistance, were the most abundant ARG and ARGC, respectively. Pseudomonadota was the dominant phylum across all sites, and Streptomyces was the most abundant genus considering all sites.

Multiple morphophysiological responses of a tropical frog to urbanization conform to the pace-of-life syndrome.

The Pace-of-Life syndrome proposes that behavioural, physiological and immune characteristics vary along a slow-fast gradient. Urbanization poses several physiological challenges to organisms. However, little is known about how the health status of frogs is affected by urbanization in the Tropics, which have a faster and more recent urbanization than the northern hemisphere. Here, we analysed a suite of physiological variables that reflect whole organism health, reproduction, metabolic and circulatory physiology and leukocyte responses in Leptodactylus podicipinus. Specifically, we tested how leukocyte profile, erythrocyte morphometrics and germ cell density, as well as somatic indices and erythrocyte nuclear abnormalities differ throughout the adult life span between urban and rural populations. We used Phenotypic Trajectory Analysis to test the effect of age and site on each of the multivariate data sets; and a Generalised Linear Model to test the effect of site and age on nuclear abnormalities. Somatic indices, erythrocyte nuclear abnormalities, erythrocyte morphometrics and leukocyte profile differed between populations, but less so for germ cell density. We found a large effect of site on nuclear abnormalities, with urban frogs having twice as many abnormalities as rural frogs. Our results suggest that urban frogs have a faster pace of life, but the response of phenotypic compartments is not fully concerted.

Proximate and fatty acid compositions oft en wild-caught and farmed fish species in mato grosso state, brazil.

This study analyzed ten fish species (three farmed and seven wild-caught) to determine their centesimal composition (assessed by AOAC methods) and lipid profile (analyzed by GC-MS). Notably, "tambatinga" (farmed) and "piraputanga" (wild-caught) stood out with 28.66 % and 26.44 % protein content and 2.32 % and 3.71 % lipid content, respectively. Across all species, oleic acid was the predominant fatty acid, followed by linoleic acid. The sum of PUFAs ranged from 17.84 % in "matrinchã" to 7.85 % in "piraputanga". SFA varied from 49.93 % in "tambacu" to 39.90 % in "matrinchã", while MUFAs ranged from 44.34 % in "palmito" to 38.39 % in "tambaqui". "Matrinchã" had the highest average ω6 acid content (16.83 %), while "cachara" had the highest average for ω3 acids (5.73 %). "Piraputanga". "cachara", and "pincachara" exhibited the lowest ω6 levels. The analysis shows that fish have excellent nutritional values (proximate compositions) with few differences between species. "Pacu", "matrinchã", and "cachara" (wild-caught) demonstrated positive attributes, while "pincachara" (farmed) exhibited the highest nutritional quality in terms of fatty acid fraction. Based on quality indices (H/H), "pacu", "matrinchã" and "pincachara" are recommended choices for a healthy diet. This study adds valuable insights into the nutritional composition of fish species, which is essential for promoting regional development and local aquaculture.

A long-term study on free-ranging jaguar-tick interactions, featuring a novel report of Amblyomma incisum adult infestation.

Over nearly 12 years, we collected ticks from free-ranging jaguars (Panthera onca) and performed statistical analyses to comprehend the vector-host relationship throughout the seasons. We evaluated the presence and number of ticks, as well as their association with weight, age, and gender of captured jaguars in the Pantanal and Amazon biomes. Out of 100 captured jaguars (comprising 72 initial captures and 28 recaptures, with 41 females and 31 males), 77 were found to be infested by different tick species. We gathered a total of 1,002 ticks, categorized by the following species in descending order of abundance: Amblyomma sculptum, Amblyomma ovale, Rhipicephalus microplus, Amblyomma triste, Amblyomma cajennense sensu stricto, Amblyomma incisum, and Amblyomma spp. larvae. Apart from weight, statistical analysis indicated that age, gender and seasonality does not significantly affect the presence of different tick species in free ranging jaguars. Notably, A. sculptum adults were more abundant in the first semester, while A. sculptum nymphs and Amblyomma spp. larvae were mainly found during dry months, aligning with their expected life cycle stages. This is the first long-term study in jaguars to correlate seasonality and host factors and also the first time an adult of A. incisum is reported infesting a jaguar.

Influence of incubation temperature and embryonic motility on the growth of members of Caiman yacare (Daudin, 1802)

Abstract This study aimed to evaluate whether skeletal development of the Pantanal Caiman (Caiman yacare) is similarly influenced by temperature variation and controlled increases in embryo motility. All eggs were incubated at 90% humidity and 29 °C for the first 45 days. Thereafter, the incubation temperature was either maintained at 29 °C and embryos were treated with 4-aminopyridine (4-AP) on days 46, 47, 48, and 49 (Group I, 29 °C 4-AP, n = 15); maintained at 29 °C (n = 14; Group II); or at 33 °C (n = 14, Group III). Embryonic movement was measured using an Egg Buddy® digital monitor on days 30, 35, 42, 49, 56, and 60, at which point embryos were euthanized and samples were collected for analysis. No differences were observed between groups with varying incubation temperatures. In contrast, embryonic motility was greater in embryos treated with 4-AP (P 0.001) on day 49, and this was associated with higher proportions of snout-vent and hand lengths. This study demonstrates for the first time that pharmacologically induced increases in embryo motility result in phenotypic changes to the proportion of elements during prenatal ontogeny, thereby effectively altering the adaptation of the species to specific environments.

Resumo Este estudo objetivou avaliar os efeitos da temperatura e motilidade embrionária sobre o desenvolvimento esquelético de jacaré-do-pantanal (Caiman yacare). Os ovos foram incubados com 90% de umidade e empregou-se a temperatura de 29°C por 45 dias. Após, para a incubação do Grupo I a temperatura continuou em 29°C, mas associou-se à injeção de 4-aminopiridina (29°C-4AP, n = 15) aplicada nos dias 46, 47, 48 e 49, do Grupo II permaneceu em 29°C (n = 14) e do Grupo III elevou-se para 33°C (n = 14). A movimentação foi mensurada através do monitor digital Egg Buddy® nos dias 30, 35, 42, 49, 56 e 60 dias. Aos 60 dias, os embriões foram eutanasiados e coletadas amostras embrionárias. Na análise estatística não foram observadas diferenças entre os grupos para o fator temperatura sobre a motilidade embrionária no desenvolvimento esquelético. Em contraste, a motilidade evidenciou diferença estatística no dia 49 para o Grupo I (P 0,001) e apresentou maiores proporções de nariz e mão. Esses dados demonstraram pela primeira vez que o aumento na motilidade, induzidos farmacologicamente resultam em divergências fenotípicas na proporção de segmentos anatômicos durante a ontogenia pré-natal, podendo alterar efetivamente a adaptação dos animais em ambientes específicos.

Influence of incubation temperature and embryonic motility on the growth of members of Caiman yacare (Daudin, 1802) / Influência da temperatura de incubação e da motilidade embrionária sobre o crescimento dos membros de Caiman yacare (Daudin, 1802)

Abstract This study aimed to evaluate whether skeletal development of the Pantanal Caiman (Caiman yacare) is similarly influenced by temperature variation and controlled increases in embryo motility. All eggs were incubated at 90% humidity and 29 °C for the first 45 days. Thereafter, the incubation temperature was either maintained at 29 °C and embryos were treated with 4-aminopyridine (4-AP) on days 46, 47, 48, and 49 (Group I, 29 °C 4-AP, n = 15); maintained at 29 °C (n = 14; Group II); or at 33 °C (n = 14, Group III). Embryonic movement was measured using an Egg Buddy® digital monitor on days 30, 35, 42, 49, 56, and 60, at which point embryos were euthanized and samples were collected for analysis. No differences were observed between groups with varying incubation temperatures. In contrast, embryonic motility was greater in embryos treated with 4-AP (P < 0.001) on day 49, and this was associated with higher proportions of snout-vent and hand lengths. This study demonstrates for the first time that pharmacologically induced increases in embryo motility result in phenotypic changes to the proportion of elements during prenatal ontogeny, thereby effectively altering the adaptation of the species to specific environments.

Resumo Este estudo objetivou avaliar os efeitos da temperatura e motilidade embrionária sobre o desenvolvimento esquelético de jacaré-do-pantanal (Caiman yacare). Os ovos foram incubados com 90% de umidade e empregou-se a temperatura de 29°C por 45 dias. Após, para a incubação do Grupo I a temperatura continuou em 29°C, mas associou-se à injeção de 4-aminopiridina (29°C-4AP, n = 15) aplicada nos dias 46, 47, 48 e 49, do Grupo II permaneceu em 29°C (n = 14) e do Grupo III elevou-se para 33°C (n = 14). A movimentação foi mensurada através do monitor digital Egg Buddy® nos dias 30, 35, 42, 49, 56 e 60 dias. Aos 60 dias, os embriões foram eutanasiados e coletadas amostras embrionárias. Na análise estatística não foram observadas diferenças entre os grupos para o fator temperatura sobre a motilidade embrionária no desenvolvimento esquelético. Em contraste, a motilidade evidenciou diferença estatística no dia 49 para o Grupo I (P < 0,001) e apresentou maiores proporções de nariz e mão. Esses dados demonstraram pela primeira vez que o aumento na motilidade, induzidos farmacologicamente resultam em divergências fenotípicas na proporção de segmentos anatômicos durante a ontogenia pré-natal, podendo alterar efetivamente a adaptação dos animais em ambientes específicos.

Phosphonate consumers potentially contributing to methane production in Brazilian soda lakes.

Oxic methane production (OMP) has been reported to significantly contribute to methane emissions from oxic surface waters. Demethylation of organic compounds, photosynthesis-associated methane production, and (bacterio)chlorophyll reduction activity are some of the investigated mechanisms as potential OMP sources related to photosynthetic organisms. Recently, cyanobacteria have often been correlated with methane accumulation and emission in freshwater, marine, and saline systems. The Brazilian Pantanal is the world's largest wetland system, with approximately 10,000 shallow lakes, most of which are highly alkaline and saline extreme environments. We initiated this study with an overall investigation using genetic markers, from which we explored metagenomic and limnological data from the Pantanal soda for five potential OMP pathways. Our results showed a strong positive correlation between dissolved methane concentrations and bloom events. Metagenomic data and nutrients, mainly orthophosphate, nitrogen, iron, and methane concentrations, suggest that the organic phosphorous demethylation pathway has the most potential to drive OMP in lakes with blooms. A specialized bacterial community was identified, including the Cyanobacteria Raphidiopsis, although the bloom does not contain the genes to carry out this process. These data showed enough evidence to infer the occurrence of an OMP pathway at Pantanal soda lakes, including the microbial sources and their relation to the cyanobacterial blooms.

The jaguar (Panthera onca) as a potential new host of Dracunculus sp.

Nematode species of the genus Dracunculus (Spirurida: Dracunculoidea) infect tissues and body cavities of reptiles, domestic and wild carnivores, and humans. The definitive hosts acquire the infection by ingesting intermediate (i.e., cyclopoid copepod) or paratenic (i.e., amphibians and fishes) hosts. Here we report the jaguar (Panthera onca) as a potential new host for Dracunculus sp. The nematode was collected from an ulcerated cutaneous nodule on the left anterior limb of a female jaguar in the municipality of Miranda, Mato Grosso do Sul state, Brazil. Based on the morphology of first stage larvae collected from a small fragment of the uterus of the adult nematode, the species was identified as Dracunculus sp. Reichard, 1759. Additionally, the morphological identification was molecularly confirmed by sequencing the cox1 gene. This report advocates for further investigations into the transmission cycle of this parasite in the Brazilian Pantanal wetland, considering the role of wildlife hosts and the zoonotic potential of Dracunculus species in that area.

Molecular evidence of Bartonella spp. in wild lowland tapirs (Tapirus terrestris), the largest land mammals in Brazil.

The genus Bartonella (Hyphomicrobiales: Bartonellaceae) encompasses facultative intracellular α-proteobacteria that parasite erythrocytes and endothelial cells from a wide range of vertebrate hosts and can cause disease in animals and humans. Considering the large diversity of vertebrate species that may act as reservoirs and arthropod species that may be associated with Bartonella transmission, the exposure of animals and humans to these microorganisms is likely underestimated. The present study aimed to investigate the occurrence of Bartonella sp. in wild tapirs (Tapirus terrestris; Perissodactyla: Tapiridae) from two biomes in Brazil: Pantanal and Cerrado. Ninety-nine GPS-monitored wild tapirs were sampled in Pantanal (n = 61/99) and Cerrado (n = 38/99). A qPCR (quantitative real-time polymerase chain reaction) assay targeting the nuoG gene was used for the screening for Bartonella spp. DNA. Positive samples were additionally subjected to conventional PCR assays targeting five molecular markers (ribC, gltA, rpoB, groEL, ITS). Eight (8/99; 08,08%) animals were positive in the qPCR assay for Bartonella spp.: 7 from Cerrado (7/8; 87.5%) and 1 from Pantanal (1/8; 12.5%). The 5 Bartonella ribC sequences obtained from tapirs' blood samples grouped together with Bartonella henselae obtained from cats, humans, wild felids and Ctenocephalides felis (Siphonaptera: Pulicidae) fleas. To the best of author's knowledge, this is the first report of Bartonella sp. in Tapirus terrestris. This finding contributes to the understanding of the occurrence of B henselae in wild mammals from Brazil as well as expands the knowledge regarding the potential vector-borne pathogens that may affect wild tapis from Cerrado and Pantanal biomes.

Insights into the organic matter composition of soda lakes in the Pantanal, Brazil, through fatty acids analysis in sediments.

We conducted a geochemical analysis on three sediment cores collected from soda and freshwater lakes in the Pantanal region, in Brazil. Our objective was to identify the primary sources of organic matter associated with the Pleistocene-Holocene transition, as previously documented in that area. The Nhecolandia region, located in the Pantanal, encompasses over 10,000 lakes, with approximately 10% of them exhibiting alkaline characteristics. Soda lakes became highly saline and alkaline after ~ 910 cal yr BP, which influences biogeochemistry and aquatic ecology. They have high electrical conductivity and pH can reach 10.5. In contrast to freshwater, soda lakes are absent of surrounding vegetation. Literature suggests a strong influence by the Last Glacial Maximum on the region. We hypothesized that periods of aridity and increased precipitation influenced the composition of organic matter present in sediments and preserved within these cores. Our analysis focused on examining the presence and distribution of fatty acids, organic carbon content, and total nitrogen. In general, the cores exhibited two distinct parts in terms of organic matter sources: the upper sections of the cores were primarily composed by terrestrial sources, identified by the presence of long-chain fatty acids, while the deeper sections were dominated by aquatic sources, therefore short-chain fatty acids. We did not find significant difference among fatty acid profile that could distinguish freshwater from soda lakes, the only remarkable difference was the occurrence of saturated fatty acids, which is lower in freshwater lake. These findings suggest the occurrence of humid and arid periods in the region. The C/N ratio displayed a similar trend to the fatty acid's profiles, exhibiting an abrupt change that was likely induced by climate variations. Although diagenesis can alter the composition of organic matter and, subsequently, the C/N values, it is noteworthy that the abrupt change observed in the Salina da Ponta (soda lake) core corresponds to 3,200 years BP. This coincides with documented climate changes that occurred during the Holocene. Our study revealed the influence of past climatic conditions on the sources and variations of organic matter in sediment cores from the Pantanal's soda and freshwater lakes. Consideration of diagenesis and climate variations is crucial for interpreting sedimentary records.

New patterns of the tree beta diversity and its determinants in the largest savanna and wetland biomes of South America.

Clear and data-driven bioregionalizations can provide a framework to test hypotheses and base biodiversity conservation. Here we used occurrence and abundance data in combination with objective analytical methods to propose two bioregionalization schemes for tree species of the Cerrado and the Pantanal in South America. We also evaluated the contribution of three sets of determinants of the occurrence- and abundance-based subregions. We compiled data on tree species composition from 894 local assemblages based on species occurrences, and from 658 local assemblages based on species abundances. We used an unconstrained community-level modelling approach and clustering techniques to identify and map tree subregions for the occurrence and the abundance data sets, separately. Hierarchical clustering analyses were conducted to investigate floristic affinities between the subregions and to map broader floristic regions. We used multinomial logistic regression models, deviance partitioning, and rank-sum tests to assess the main subregion correlates. We identified 18 occurrence- and four abundance-based subregions in the Cerrado-Pantanal. The hierarchical classifications grouped the occurrence-based subregions into nine floristic zones and abundance-based subregions into two broad floristic zones. Variation in subregions were explained mainly by environmental factors and spatial structure in both occurrence and abundance data sets. The occurrence- and abundance-based subregions are complementary approaches to disentangle macroecological patterns and to plan conservation efforts in the Cerrado and the Pantanal. Our findings based on occurrence data revealed more complex and interdigitated boundaries between subregions of tree species than previously reported. The environment, historical stability, and human effects act in a synergetic way on the distribution of the subregions. Finally, the relevance of contemporary environmental factors to the subregion patterns we found alert us to the profound impact global warming may have on the spatial organization of the Cerrado-Pantanal tree flora.

Molecular prevalence and factors associated with Ehrlichia canis infection in dogs from the North Pantanal wetland, Brazil.

Background and Aim: Canine monocytic ehrlichiosis is a vector-borne disease caused by the obligatory intracellular bacterium Ehrlichia canis, which is distributed across tropical and subtropical regions worldwide. Its prevalence within dog populations is high in municipalities located across the Pantanal biome, but it remains unknown in Barão de Melgaço, Mato Grosso, Brazil. This study aimed to determine the molecular prevalence and factors associated with E. canis infection in dogs domiciled in Barão de Melgaço. Materials and Methods: A cross-sectional study was carried out to investigate the prevalence of E. canis infection in 369 dogs from urban and rural areas in Barão de Melgaço, North Pantanal wetland, Brazil. Initially, the dogs were examined, and, through a questionnaire, the risk factors were investigated. Blood samples were subjected to DNA extraction and PCR was performed to estimate the prevalence of E. canis infection. Results: The molecular prevalence of E. canis infection in dogs was 42.5% and none of the studied variables were significantly associated with polymerase chain reaction (PCR) positivity (p > 0.05). Conclusion: The high molecular prevalence demonstrates an increased transmission of the agent across the city. This also indicates that attention needs to be paid to E. canis infection and control measures should be introduced to prevent its transmission. The demographic and clinical risk factors commonly associated with E. canis infection in this study were not associated with PCR positivity.

Among-species variation in flower size determines florivory in the largest tropical wetland.

PREMISE: Flower damage caused by florivores often has negative consequences for plant reproduction. However, the factors affecting plant-florivore interactions are still poorly understood, especially the role of abiotic factors and interspecific variation in florivory within ecosystems. Thus, the patterns of florivory levels and its consequences for plant communities need to be investigated further. METHODS: We assessed the influence of abiotic factors related to climatic seasonality, of phylogenetic relationships among plants, and of functional attributes associated with attractiveness to pollinators on florivory incidence and intensity in the Pantanal, the world's largest tropical wetland. Between December 2020 and November 2021, the percentage of flowers attacked (incidence) and petal area removed (intensity) by florivores were examined in 51 species from 25 families, considering flowering season, the substrate where the plants occur, and flower attributes as potentially determining factors on florivory levels. RESULTS: Phylogeny and environmental factors did not have a significant influence on florivory. The only determinant of interspecific variation in florivory incidence and intensity was flower size, where larger flowers experienced higher florivory levels regardless of season and substrate, while flower arrangement and color were not significant factors. CONCLUSIONS: Our study is one of the first to estimate the community-wide effects of biotic and abiotic factors on both the incidence and the intensity of florivory. The magnitude of this plant-florivore interaction may reduce reproductive success and entail selective pressures on plant attractiveness to pollinators.

Unveiling demographic and mating strategies of Panthera onca in the Pantanal, Brazil.

We conducted the first long-term and large-scale study of demographic characteristics and reproductive behavior in a wild jaguar (Panthera onca) population. Data were collected through a combination of direct observations and camera trapping on a study area that operates both as a cattle ranch and ecotourism destination. Jaguars exhibited two birth peaks: April/May and October/November, that are the end and the beginning of the wet season in the Pantanal, respectively. The average litter size was 1.43 ± 0.65. Single cubs made up a total of 65.7% of the births, and we found a slight predominance of females (1.15:1 ratio) in litters. The mean age at independence was 17.6 ± 0.98 months, with sex-biased dispersal, with all males (n = 27) leaving the natal home range and 63.6% of females exhibiting philopatry. The interbirth intervals were 21.8 ± 3.2 months and the mean age at first parturition was 31.8 ± 4.2 months. Our results estimated a lifetime reproductive success for female jaguars of 8.13 cubs. Our observations also indicate that female jaguars can display mating behavior during cub rearing or pregnancy, representing 41.4% of the consorts and copulations recorded. We speculate that this behavior has evolved as a defense against infanticide and physical harm to the female. To our knowledge, this is the first time that such behavior is described for this species. All aggressive interactions between females involved the presence of cubs, following the offspring-defense hypothesis, that lead to territoriality among females in mammals, regardless of food availability. In the face of growing threats to this apex predator, this work unveils several aspects of its natural history, representing a baseline for comparison with future research and providing critical information for population viability analysis and conservation planning in the long term.

Este é o primeiro estudo de longo prazo e em grande escala de características demográficas e de comportamento reprodutivo em uma população selvagem de onças-pintadas (Panthera onca). Os dados foram coletados por meio de uma combinação de observações diretas e armadilhamentos fotográficos em uma área de estudo que atua tanto como fazenda de pecuária quanto como destino ecoturístico. As onças-pintadas apresentaram dois picos de nascimento: abril/maio e outubro/novembro, que são o final e o início da estação chuvosa no Pantanal, respectivamente. O tamanho médio da ninhada foi 1.43 ± 0.65. Filhotes únicos representaram um total de 65.7% dos nascimentos, e encontramos uma ligeira predominância de fêmeas (proporção 1.15:1) nas ninhadas. A idade média de independência foi de 17.6 ± 0.98 meses, com uma dispersão sexo-assimétrica, com todos os machos (n = 27) deixando a área natal e 63.6% das fêmeas apresentando filopatria. O intervalo entre ninhadas foi de 21.8 ± 3.2 meses e a idade média da primeira cria foi de 31.8 ± 4.2 meses. Nossos resultados estimaram um sucesso reprodutivo médio ao longo da vida para onças-pintadas fêmeas de 8.13 filhotes. Nossas observações também indicam que as onças-pintadas fêmeas podem apresentar comportamento de acasalamento durante a criação dos filhotes ou da gestação, representando 41.4% das cortes e cópulas registradas. Especulamos que esse comportamento tenha evoluído como uma defesa contra infanticídio e danos físicos à fêmea. Segundo nosso conhecimento, está é a primeira vez que tal comportamento é descrito para esta espécie. Todas as interações agressivas entre fêmeas envolveram a presença de filhotes, seguindo a hipótese de defesa da prole, que levam à territorialidade entre fêmeas em mamíferos, independentemente da disponibilidade de alimento. Diante das crescentes ameaças a este predador de topo, este trabalho revela vários aspectos de sua história natural, representando uma base de comparação com pesquisas futuras e fornecendo informações críticas para a análise de viabilidade populacional e planejamento de conservação em longo prazo.

Immature hard ticks infected with Rickettsia amblyommatis on breeding birds from Pantanal.

Immature hard ticks from the genus Amblyomma feed on blood from a wide range of Neotropical avian hosts. They serve as vectors for pathogens of medical and veterinary importance, such as Rickettsia agents of the spotted fever group (SFG). Hence, determining ecological factors that increase encounter rates between immature ticks and their avian hosts may contribute to the understanding of tick-borne diseases transmission. Here, we used 720 individual birds from 96 species surveyed in the Brazilian Pantanal to test whether host breeding season influenced tick infestation probabilities. Additionally, collected ticks were screened for Rickettsia agents to describe new avian-tick-bacteria associations. Our models revealed that the probability of an individual bird being infested with immature ticks was similar during the breeding and pre-breeding season, but higher loads of immature tick stages were found during the breeding season. Host sex did not predict infestation probability, but Rickettsia agents recovered from ticks were more prevalent during the pre-breeding season. The new records of host usage by larvae and nymphs of Amblyomma in Pantanal and the growing body of tick surveys in Neotropical avian communities, suggest that immature ticks may benefit from avian blood sources during their annual cycle. The low number of infected ticks with Rickettsia agents on Pantanal birds suggest that this vertebrate group are likely not acting as reservoirs for these microorganisms. However, long-term surveys at the same site are imperative to determine which tick species are acting as reservoirs for Rickettsia agents in Pantanal and determine whether birds are playing a role in dispersing ticks and tick-borne pathogens.

Posts Supporting Anti-Environmental Policy in Brazil are Shared More on Social Media.

Weakening environmental laws supported by disinformation are currently of concern in Brazil. An example of disinformation is the case of the "firefighter cattle". Supporters of this idea believe that by consuming organic mass, cattle decrease the risk of fire in natural ecosystems. This statement was cited by a member of the Bolsonaro government in response to the unprecedented 2020 fires in the Pantanal, as well as in support of a new law that enables extensive livestock in protected areas of this biome. By suggesting that grazing benefits the ecosystem, the "firefighter cattle" argument supports the interests of agribusiness. However, it ignores the real costs of livestock production on biodiversity. We analysed the social repercussion of the "firefighter cattle" by analysing public reactions to YouTube, Facebook, and Google News posts. These videos and articles and the responses to them either agreed or disagreed with the "firefighter cattle". Supportive posts were shared more on social media and triggered more interactions than critical posts. Even though many netizens disagreed with the idea of "firefighter cattle", it has gone viral, and was used as a tool to strengthen anti-environmental policies. We advocate that government institutions should use resources and guidelines provided by the scientific community to raise awareness. These materials include international reports produced by the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) and the Intergovernmental Panel on Climate Change (IPCC). We need to curb pseudoscience and misinformation in political discourse, avoiding misconceptions that threaten natural resources and confuse global society.

Theileria terrestris nov. sp.: A Novel Theileria in Lowland Tapirs (Tapirus terrestris) from Two Different Biomes in Brazil.

The low-land tapir (Tapirus terrestris) is the largest wild terrestrial mammal found in Brazil. Although T. terrestris has been already reported as a host of hemoparasites, the occurrence and genetic identity of Piroplasmida agents in this species is still cloudy. Although it is reported that Theileria equi, an endemic equid-infective agent in Brazil, is occurring in lowland tapirs, these reports are probably misconceived diagnoses since they are solely based on small fragments of 18S rRNA that may not achieve accurate topologies on phylogenetic analyses. The present study aimed to detect and investigate the identity of Theileria spp. in tapirs from Pantanal and Cerrado biomes. Blood-DNA samples from tapirs were screened for a partial (~800 bp) 18S rRNA gene fragment from Piroplasmida and 64 (64/122; 52.46% CI: 43.66-61.11%) presented bands of expected size. Samples were submitted to different protocols for molecular characterization, including near-full length 18S rRNA gene (~1500 bp), and the ema-1 gene from T. equi. Eight sequences were obtained for extended fragments (1182-1473 bp) from the 18S rRNA gene. Moreover, three sequences from partial cox-1 and five from partial hsp70 gene were obtained. None of the samples presented amplifications for the ema-1 gene. Phylogenetic and distance analyses from the 18S rRNA sequences obtained demonstrated a clear separation from tapirs' Theileria spp. and T. equi. Phylogenetic analyses of cox-1 and hsp70 sequences obtained herein also showed a unique clade formed by tapir's Theileria spp. Theileria terrestris sp. nov. is positioned apart from all other Theileria species in 18S rRNA, cox-1, and hps70 phylogenetic analyses. This novel proposed species represents a new Piroplasmida clade, yet to be characterized regarding biological features, vectors involved in the transmission cycles, additional vertebrate hosts, and pathogenicity.

Human risk assessment of ash soil after 2020 wildfires in Pantanal biome (Brazil).

Wildfires have increased in the last years and, when caused by intentional illegal burnings, are frequently run out of control. Wildfire has been pointed out as an important source of polycyclic aromatic hydrocarbons (PAHs) and trace elements (TEs) - such as, As, Ni, and Pb - to environmental compartments, and thus may pose a risk to human health and to the ecosystem. In 2020, the Brazilian biome, Pantanal, faced the largest losses by wildfires in the last 22 years. Ashes from the topsoil layer in Pantanal were collected after these wildfires at 20 sites divided into the sediment, forest, PF, PS, and degraded sites. Toxicity and associated risks for human health were also evaluated. The areas highly impacted by wildfires and by artisanal gold mining activities showed higher concentrations for TEs and PAHs than the protected areas. Pb varied from 8 ± 4 to 224 ± 81 mg kg-1, and total PAH concentration ranged between 880 ± 314 and 1350 ± 70 ng g-1, at sites impacted by anthropogenic activities. Moreover, health risk assessments for TE and PAH indicated a potentially great risk for children and adults, via ingestion, inhalation, and dermal pathway. The carcinogenic risks exceeded reference values, for both TE and PAH, suggesting harmful conditions, especially for vulnerable groups, such as children and the elderly. Supplementary Information: The online version contains supplementary material available at 10.1007/s11869-022-01248-2.