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This study performed a serological assay to assess the exposure of free-ranging cougars (Puma concolor) to four selected infectious agents, including Toxoplasma gondii, Leptospira spp., the feline immunodeficiency virus (FIV), and the feline leukemia virus (FeLV). Serum samples were collected from 27 free-ranging cougars along the Tietê River Basin, in the central region of the State of São Paulo, Brazil. The presence of antibodies against T. gondii was detected in 59.3% (16/27) of the serum samples through the modified agglutination test (MAT-t), which was the most prevalent agent. The microscopic agglutination technique (MAT-1) was used to investigate the occurrence of anti-Leptospira spp. antibodies, showing that 11.1% (3/27) of the sampled cougars were seropositive. The only serovar detected was Djasiman (L. interrogans). A commercial enzyme-linked immunosorbent assay (ELISA) licensed for use in domestic felines was used to investigate the occurrence of retroviruses. The ELISA test kits detected a prevalence of 11.1% (3/27) of FIV antibodies, while none of the samples tested showed any evidence of FeLV antigen. These results suggest that free-ranging cougars are exposed to potentially pathogenic agents. This study presented the first recorded occurrence of the serovar Djasiman in P. concolor.

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Ecological associations between wild felids and parasites from the Taeniidae family are related to predator-prey interactions, where felids act as definitive hosts while their prey, herbivores and/or omnivores, act as intermediate hosts. In the Atlantic Forest, six neotropical felid species coexist in sympatry, but the ecological parasite-host interactions remain poorly studied. Taenia omissa is a tapeworm that parasitizes cougars (Puma concolor) as its only definitive host and their ungulate prey as intermediate hosts. The aim of this study was to identify tapeworms present in road-killed fauna using both molecular and morphological characteristics and their predator-prey relationship. Adult tapeworms found in a cougar, a jaguarundi (Herpailurus yagouaroundi), and two ocelots (Leopardus pardalis); and metacestodes found in a red brocket deer (Mazama americana) and a wild guinea pig (Cavia aperea) were analyzed. Through morphological analysis of rostellar hooks and molecular analysis of the mitochondrial genetic marker cox1, Taenia omissa adult individuals were identified in the cougar, and metacestodes in the red brocket deer, proving the existence of a full host-parasite life cycle in the Atlantic Forest region. This new report reveals the southernmost record of T. omissa and broadens its geographic distribution. In addition, isolates of the Taenia genus divergent from those described so far in molecular databases were reported and suggested a wild cycle that involves the jaguarundi and agouti (Dasyprocta asarae) as definitive and intermediate hosts, respectively. These results highlight the complexity of the tapeworm population in the region and the need to study it with both morphological and molecular approaches.

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Parasites of the Cylicospirura genus are known to affect domestic and wild carnivores by causing the formation of nodules within the gastric mucosa and pyloric region of parasitized animals. C. felineus is a specimen of this genus that has been reported in Brazil in animal species such as Leopardus geoffroyi and Puma concolor. However, as far as the authors of the present study are aware, reports of C. felineus in jaguarundis (Puma yagouaroundi) do not yet exist. This wild feline species native to the Americas is found only in a few countries - and it is possibly extinct in others, such as the United States. In Brazil, the P. yagouaroundi species is classified as vulnerable by government environmental agencies. Consequently, identifying the diseases and their relevance to this species is of utmost importance for P. yagouaroundi's preservation. This study aims to describe the histopathological lesions found in jaguarundis parasitized by the genus Cylicospirura, and to identify the parasitic species observed in these animals. Eight specimens of P. yagouaroundi necropsied between 2010 and 2020 in the Laboratory of Veterinary Pathology of the Federal University of Paraná (UFPR) in Palotina, Brazil, were studied. Seven specimens were wildlife roadkills, and one was from the Municipal Zoo of Cascavel, Paraná, Brazil. Seven of the necropsied animals presented - in the greater curvature of the stomach, near the cardia - one or more parasitic nodules of 0.5 to 3.0 cm in diameter that contained several intralesional reddish filiform parasites. Histologically, these nodules were characterized as transmural parasitic granulomas surrounded by reaction with deposition of dense connective tissue. The parasitological evaluations by light and scanning electron microscopy identified morphological C. felineus' characteristics through the presence of unequal spicules in males, the position of the vulva, and location of the pedunculated papillae. Despite the gastric lesion caused by the parasite, the apparent low pathogenicity to the gastrointestinal system of the evaluated animals, massive infections or large nodules can lead to death - other members of the Spirocercidae family are known to cause organ rupture, esophageal obstructions, and mesenchymal neoplasms. Therefore, C. felineus should be included in the list of gastric parasites with pathogenic potential in the species P. yagouaroundi.

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The semi-arid Caatinga is the largest dry forest ecoregion in the Americas; nevertheless, it is experiencing alarming rates of habitat loss. Most vegetation fragments in the biome are either unprotected or within private lands; however, these private areas are susceptible to anthropogenic activity, and often have the presence of non-native wildlife such as domestic dogs and cats. Two small felid species, the northern tiger cat and the jaguarundi co-occur throughout the Caatinga and have overlapping niches, which require segregation mechanisms to avoid interference competition. Assessing these species strategies for coexistence is crucial, as it can guide conservation actions. With this aim, a private ranch in the Brazilian Caatinga drylands was surveyed and multi-species occupancy models were used to assess co-occurrence patterns between northern tiger cats and jaguarundis. The degree of temporal overlap between both felids and domestic dogs and cats were also assessed. Evidence was found of positive co-occurrence between tiger cats and jaguarundis, suggesting a lack of spatial segregation at our study site; and low temporal overlap was found between both felids, with tiger cats being nocturnal and jaguarundis diurnal. High temporal overlap was found though between domestic dogs and both wild felid species. Our results suggest that small felids can coexist in private areas of the Caatinga with sufficient habitat. However, there is a need to highlight the potential threat of disease transmission by non-native carnivores as something that should be addressed in these private landscapes.

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Monitoring wildlife populations to determine changing abundance is the basis for conservation strategies and interventions. Monitoring, however, is expensive, and we lack baseline data for countless species and landscapes around the globe. One solution is to utilize methods that leverage observations collected by everyday people. Humans are not only excellent sensors for diverse data, but possess a remarkable ability to process data and differentiate patterns with minimal training. Here, we explored the potential for people, including guides who work in tourism in southern Patagonia, to determine whether paired photographs of puma (Puma concolor puma) faces were the same individual, akin to a computer-led Siamese network analysis. Overall, participants performed well (average score of 92.2 %) and we detected no differences in local people versus those from the USA, or differences due to differential experience working with pumas. Based on these results, we built a historic capture-recapture dataset of individual pumas collected by local guides and report annual abundance for a portion of the Torres del Paine UNESCO Biosphere in southern Chile, an area lacking such data and of critical conservation for the species. Our results highlight the innate capabilities of human computers and their potential for contributing to wildlife surveys in novel ways to increase science capacity.

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Human activities such as habitat degradation and fragmentation threaten biodiversity in Neotropical areas. This work proposes an analytical methodology to identify natural areas in Central America with anthropogenic impact, analyzing the presence of antimicrobial resistance genes (ARGs) in accordance with their theoretical relationship with human-related activities. Sixteen ARGs were quantified in feces of different individuals of 13 jaguars (Panthera onca) and 13 pumas (Puma concolor) in three conservation areas in Costa Rica by real-time PCR. At least one ARG was detected in all samples. Of the ARGs encoding tetracycline resistance, the most frequent were tetQ and tetY (85% and 69%, respectively). The sulfonamides (sulI and sulII; 69% each), phenicols (catI and catII; 19% and 54%, respectively), and quinolones (qnrS; 12%) were also detected. The presence of human settlements, livestock farms (pigs, cattle, and poultry), roads, human health centers, flood zones, and rivers were identified within each area to generate an index of human activity. We found no difference between the presence of ARG by roads, agricultural activities, and human settlements (P>0.05). However, tetW showed higher percentages with porcine and bovine farms; both tetY and tetW were more frequent in jaguars than in pumas. Of concern is that many of the most contaminated samples were taken from national parks, such as Braulio Carrillo and Tortuguero, where animals should not have direct contact with humans.

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The effects of predation risk on prey populations have been studied extensively; yet, how risk is manifested in a trophically linked guild-scavengers-has been overlooked. Risk could be particularly consequential for obligate scavengers that are vulnerable while foraging and rely on carrion provisioned by, and shared with, apex predators. We investigated whether Andean condors (Vultur gryphus) respond to predation risk in a landscape where the main source of carrion are camelids killed by pumas (Puma concolor). We hypothesized that condors would exhibit different behavioral responses to predation risk while they search, encounter, and exploit carrion. We explored condor habitat selection while flying by tracking nine birds with satellite transmitters and monitored via camera traps 41 natural carcasses and 25 experimental carrion stations. We found that condors searched for carrion in areas with a high probability of occurrence of puma kills. However, condors avoided exploiting carrion in areas featuring tall vegetation and steep slopes-selected by pumas to stalk prey-suggesting that condors manage risk primarily through the identification of safe foraging sites prior to landing. Our finding that condors avoided foraging near stalking cover for pumas highlights the importance of risk effects beyond predator-prey interactions, particularly for obligate scavengers.

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The loss of wild biodiversity has prompted the development of cryobanks, such as those of somatic cells. This is the reality of Pumas, wild felids of ecological importance that suffer from anthropogenic actions, population decline, and subsequent loss of genetic diversity. Somatic cell banks are a strategy for conserving population diversity. We compared different concentrations and types of intracellular cryoprotectants (dimethyl sulfoxide, DMSO; ethylene glycol, EG) associated with 0.2 M of sucrose (SUC) in the cryopreservation of the somatic cells of captive Pumas. The cells were cryopreserved by slow freezing with different solutions containing Dulbecco's modified Eagle's medium with 10% fetal bovine serum and varying concentrations of DMSO and EG in the absence or presence of SUC. The cells were analyzed for morphological characteristics, viability, proliferative activity, metabolic activity, and apoptosis levels. Cells maintained similar fusiform morphology before and after cryopreservation. There was no difference in viability, regardless of the reduction in the concentration and type of intracellular cryoprotectants and sucrose. Similarly, proliferative activity, metabolic activity, and apoptosis levels were not altered by the composition of the cryoprotectants. In summary, we demonstrate that reducing the concentration of DMSO or EG ensures adequate cryopreservation of Puma somatic cells, regardless of the presence of SUC.

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Research Highlight: Lundgren, E. J., Ramp, D., Middleton, O. S., Wooster, E. I. F., Kusch, E., Balisi, M., Ripple, W. J., Hasselerharm, C. D., Sanchez, J. N., Mills, M. & Wallach, A. D. (2022) A novel trophic cascade between cougars and feral donkeys shapes desert wetlands. Journal of Animal Ecology, (91, 2010-2022). https://doi.org/10.1111/1365-2656.13766. Despite being absent from most regions of the contemporary world, megafauna species dominated the dynamics of ecological communities until the late Pleistocene. Trophic rewilding is a promising approach to restoring megafauna interactions, their functional roles and the consequent trophic cascades. Unintentional rewilding with large non-native herbivores, such as equids, offers outstanding opportunities for ecologists to understand the outcomes of using replacement species to restore the ecological functions of extinct native megafauna. In this context, it is relevant to understand the extent to which extant native predators can impose top-down control on non-native megaherbivores and how trophic cascades arising from novel predator-prey interactions influences biodiversity and ecosystem functions. In Death Valley National Park (United States), Lundgren et al. depict a natural experiment showing compelling evidence of native cougars overcoming ecological naïveté-that is, the mismatches between predator and prey species that do not share a common evolutionary history-and are now successfully preying on younger individuals of feral donkeys. These non-native donkeys, whose growing wild populations threaten the native biota, became cougars' most frequent dietary item in that region. In areas with cougars, donkeys changed their spatiotemporal foraging patterns, becoming diurnal and less active. On the other hand, donkeys remain more active and forage throughout the day and night in areas without cougars. The cougar-donkey interaction triggered a behaviourally mediated trophic cascade emerging from a 'landscape of fear', that is, from the perception of spatial heterogeneity in predation risk by donkeys. Areas with cougars have less trampled ground, fewer donkey trails, and much more canopy cover and vegetation around water. Donkeys concentrate their activity mostly in topologically plain terrains lacking proper sites for the ambush behaviour of cougars and with more intense human presence, likely acting as a shield against the predators. Lundgren et al. present a promising model system for studying the effects of fearful grazers on community structure in the context of novel ecological interactions being established in the Anthropocene. Whether the emerging cascade is transient or persistent, the relative roles of consumptive and non-consumptive effects as underlying mechanisms, and their consequences for food web structure, functioning and stability, are questions of general interest. Addressing them can help us to elucidate the costs and benefits of using non-native megaherbivores in the functional restoration of permanently invaded ecosystems.

Pesquisa em Destaque: Lundgren, E. J., Ramp, D., Middleton, O. S., Wooster, E. I. F., Kusch, E., Balisi, M., Ripple, W. J., Hasselerharm, C. D., Sanchez, J. N., Mills, M. & Wallach, A. D. (2022) A novel trophic cascade between cougars and feral donkeys shapes desert wetlands. Journal of Animal Ecology, 00:00-00. https://doi.org/10.1111/1365-2656.13766. Apesar de estarem ausentes da maioria das regiões do mundo contemporâneo, as espécies da megafauna dominaram a dinâmica das comunidades ecológicas até o Pleistoceno tardio. A refaunação trófica é uma abordagem promissora para a restauração das interações da megafauna, de seus papéis funcionais e das cascatas tróficas delas decorrentes. A refaunação não-intencional com grandes herbívoros não-nativos, tais como equídeos, oferece oportunidades extraordinárias para os ecólogos entenderem as consequências do uso de espécies substitutas para restaurar as funções ecológicas da extinta megafauna nativa. Nesse contexto, é relevante entendermos o quanto os predadores nativos atuais podem impor controle de cima para baixo sobre mega-herbívoros não-nativos, e como cascatas tróficas oriundas de novas interações predador-presa influenciam a biodiversidade e as funções ecossistêmicas. No Parque Nacional do Vale da Morte (Estados Unidos), Lundgren et al. reportam um experimento natural mostrando evidências contundentes de que onças pardas superaram a ingenuidade ecológica - i.e., os desajustes entre predadores e presas que não compartilham uma história evolutiva comum - e agora estão predando os indivíduos mais jovens de burros ferais com sucesso. Esses burros exóticos, cujas populações crescentes ameaçam a biota nativa, se tornaram o item mais frequente da dieta das onças pardas nessa região. Em áreas com onças pardas, os burros mudaram seus padrões espaço-temporais de forrageio, tornando-se diurnos e menos ativos. Por outro lado, os burros permanecem mais ativos e forrageiam durante o dia e à noite em áreas sem onças pardas. A interação entre onças pardas e burros desencadeou uma cascata trófica comportamentalmente mediada que emerge de uma "paisagem de medo", isto é, da percepção dos burros sobre a heterogeneidade espacial do risco de predação. Áreas com onças pardas tiveram menos solo pisoteado, menos trilhas de burros, e muito mais cobertura de dossel e vegetação no entorno da água. Os burros concentram a maior parte de suas atividades em terrenos topologicamente planos, os quais não apresentam lugares apropriados para o comportamento de emboscada das onças pardas e têm presença humana mais intensa, provavelmente agindo como escudos contra predadores. Lundgren et al. apresentam um sistema modelo promissor para o estudo de efeitos de pastadores temorosos sobre a estrutura comunitária no contexto de novas interações ecológicas em estabelecimento no Antropoceno. Se a cascata trófica emergente é transiente ou persistente, os papéis relativos dos efeitos diretos e indiretos como mecanismos subjacentes, e suas consequências para a estrutura, funcionamento e estabilidade da teia trófica são questões de interesse geral. Respondê-las pode nos ajudar a elucidar os custos e benefícios de usar mega-herbívoros não-nativos na restauração funcional de ecossistemas permanentemente invadidos.

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Trichinella spp. are zoonotic parasites that are widely distributed in warm-blooded carnivores and omnivores, including humans. Until the present moment, Brazil has been considered by World Animal Health Organization free from the domestic cycle of trichinellosis, whereas the parasite's sylvatic cycle has the status of infection in limited zones. However, neighboring countries such as Argentina have reports of parasite larvae in the wild fauna. The present study aimed to determine the occurrence of Trichinella spp. in road-killed wild animals in Paraná, Brazil. Biological samples from 71 wild animals-29 Didelphis albiventris, 11 Nasua nasua, ten Cerdocyon thous, seven Dasypus novemcinctus, six Leopardus guttulus, six Sphiggurus spinosus and two Puma concolor-collected from November 2016 to November 2021 were subjected to artificial digestion, following the methodology described in the REGULATION (EC) No. 2075/2005. No Trichinella spp. larvae were detected in the carcasses of the road-killed wild animals. However, considering the wide spectrum of possible reservoirs that could act as a link between the sylvatic and domestic cycles and considering the current Brazilian status of sylvatic trichinellosis in limited zones, frequent monitoring of wild fauna remains necessary.

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