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Toxoplasmosis is an important zoonotic disease that affects a wide range of warm-blooded host species. Neotropical primates (New World Primates; NWP) are highly susceptible, developing a lethal acute systemic disease. Toxoplasmosis in free-ranging NWP is poorly described, with only a few studies based on serosurveys. Herein we performed a retrospective study focusing on the epidemiology and pathology of toxoplasmosis among 1,001 free-ranging marmoset (Callithrix spp.) deaths from the Brazilian Atlantic Forest. This study included marmosets necropsied at the Instituto Municipal de Medicina Veterinária Jorge Vaitsman (IJV) from January 2017 to July 2019, which were found dead from all regions in the State of Rio de Janeiro. Histopathology, immunohistochemistry, and transmission electron microscopy were performed to better characterize toxoplasmosis in this free-ranging population. All samples were also tested for Yellow Fever Virus (YFV) RT-qPCR by the official diagnostic service. A total of 1,001 free-ranging marmosets were included in this study, with 16 (1.6%) cases of lethal Toxoplasma gondii infections identified both as individual cases and in outbreaks. Presence of infection was not associated with sex, age, geographical distribution, or year of death, and no co-infection with YFV was observed. The main pathological feature in these cases was random necrotizing hepatitis with detection of intralesional T. gondii zoites in all infected cases. Interstitial pneumonia rich in alveolar foamy macrophages and fibrin deposition, necrotizing myocarditis and necrotizing splenitis were also pathological features in affected marmosets. Therefore, toxoplasmosis was considered the cause of death in 1.6% of free-ranging marmosets in this retrospective series, including some cases associated with outbreaks. Necrotizing random hepatitis was a consistent pathological finding in affected cases and sampling of liver should be ensured from Callitrichid post mortem cases. Author summary: Toxoplasmosis is an important zoonotic disease that represents a concern to captive neotropical primates, due to its high susceptibility, with quick lethal course. Large studies of the pathology and epidemiology of toxoplasmosis in in wildlife neotropical primates are rare, rendering it difficult to evaluate the impact of this disease in free-ranging population. This study investigated toxoplasmosis-induced deaths in 1,001 free-ranging marmosets, describing its epidemiology, pathology, and diagnostic tools. Also, this study highlights the importance of histopathology in the differential diagnosis of other important zoonotic diseases that may circulate in that population, such as Yellow Fever. [ABSTRACT FROM AUTHOR]

The last decades are witnessing a growing concern about environmental impacts due to human activities. Within this context, studies are being developed to understand the impacts on the diversity of natural elements. This article presents a method to identify geomorphological diversity hotspots at a detailed scale through a quantitative approach, which was applied to a protected coastal area in Rio de Janeiro State, SE Brazil. These hotspots are understood as areas that present significant diversity of landforms and, at the same time, risks of degradation, which justifies the definition of priorities for the territorial management aiming at nature conservation purposes. The results allowed the identification of five hotspots, showing that, even though the area is legally protected, it still faces problems related to threats caused by human activities. Therefore, specific problems of territorial management in a protected area were identified through the creation of a product that indicates the priority areas for conservation in a different way and can be easily applied as a tool to support managers. Furthermore, several subproducts were created in the process, which also can be used for other purposes. • The hotspot map is a tool for the definition of priority areas for conservation. • Threat fronts and threatened landforms can be identified by the threat index map. • All the index and subindex maps present relevant management information. [ABSTRACT FROM AUTHOR]