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In this work, we examined the levels of vitamin E in the heart, liver, and kidneys of four species of adult male bats with distinct feeding habits. Our results indicate consistent vitamin E levels in the heart across all four bat species, suggesting the presence of regulatory mechanisms. Additionally, the liver displayed notably higher vitamin E levels in nectarivorous and frugivorous bats, while hematophagous bats exhibited lower levels, indicating a link between dietary intake and liver vitamin E levels. Furthermore, correlation analysis provided additional insights into the relationships between vitamin E and key antioxidant parameters in the livers of bats. On the other hand, no correlation was observed between vitamin E and key antioxidant parameters in the heart. Intriguingly, vitamin E was not detected in the kidneys, likely due to physiological factors and the prioritization of vitamin E mobilization in the heart, where it serves critical physiological functions. This unexpected absence of vitamin E in bat kidneys highlights the unique metabolic demands and prioritization of vitamin mobilization in wild animals like bats, compared to conventional animal models. These findings provide insight into the intricate distribution and utilization of vitamin E in bats, emphasizing the influence of dietary intake and metabolic adaptations on vitamin E levels in different organs.

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The aim of this study was to compare the oxidative metabolism of four neotropical bat species with different feeding habits and investigate the relationship between their feeding habits and oxidative status. In terms of oxidative damage, our findings revealed major differences among the four bat species. In particular, hematophagous bats had lower levels of oxidative damage in the heart but higher levels in the liver. Nectarivorous bats had lower levels of carbonyl groups in the kidneys compared to insectivorous and hematophagous bats. The activity of various antioxidant and non-antioxidant enzymes in the heart, liver, and kidney also showed significant differences among the bat species. H2O2 consumption was lower in the heart of hematophagous bats, while insectivorous bats exhibited the highest enzymatic activity in the kidney. SOD activity was lower in the heart of hematophagous bats and lower in nectarivorous bats in the liver. Fumarase activity was higher in the heart of frugivorous/insectivorous and lower in nectarivorous/hematophagous bats. GPx activity was higher in the heart of nectarivorous/insectivorous and higher in the kidney of insectivorous bats. GST activity was higher in the heart of nectarivorous and lower in hematophagous bats. The correlation analysis between oxidative markers and enzymatic/non-enzymatic antioxidants in the heart, liver, and kidney exhibited distinct patterns of correlations due to variations in antioxidant defense mechanisms and oxidative stress responses in different organs. The observed differences in oxidative damage, antioxidant enzyme activities, and correlations between oxidative markers and antioxidants highlight the adaptability and complexity of the antioxidant defense systems in these bats. Each organ appears to have specific demands and adaptations to cope with oxidative stress based on its physiological functions and exposure to dietary components. Our results have major significance for the conservation and management of bats, which are threatened species despite being crucial components of ecosystems. Our study's implications go beyond bat biology and offer valuable insights into comparative oxidative physiology.

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Assessing the levels of oxidative stress markers and antioxidant enzymes in the brain is crucial in evaluating its antioxidant capacity and understanding the influence of various dietary patterns on brain well-being. This study aimed to investigate the antioxidant status and oxidative damage in the brain of bat species with different feeding habits to gain insights into their protective mechanisms against oxidative stress and their interspecific variation. The levels of oxidative damage markers and the activities of antioxidants were measured in the brain of four bat species with different feeding habits, namely insectivorous, frugivorous, nectarivorous, and hematophagous. Insectivorous bats showed higher levels of SOD and fumarase compared to the other groups, while hematophagous bats showed lower levels of these enzymes. On the other hand, the activities of glutathione peroxidase and glutathione S-transferase were higher in hematophagous bats and lower in insectivorous bats. The carbonyl groups and malondialdehyde levels were lower in frugivores, while they were similar in the other feeding guilds. Nitrite and nitrate levels were higher in the hematophagous group and relatively lower in all other groups. The GSSG/GSH ratio was higher in the hematophagous group and lower in frugivores. Overall, our results indicate that the levels of oxidative stress markers and the activities of antioxidant enzymes in the brain vary significantly among bat species with different feeding habitats. The findings suggest that the antioxidant status of the brain is influenced by diet and feeding habits.

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Chemical profiles of non-invasive biological material, such as feces, have great potential to study elusive animals or those with low population densities. Here, we use a metabolomic approach to evaluate Neotropical mustelids as a biological model to describe the diversity of the metabolites present in fecal samples, as well as to evaluate the potential of chemical profiles for taxonomic discrimination. We collected fecal samples from captive individuals of 5 species of mustelids occurring in Brazil and analyzed them by liquid chromatography coupled to high-resolution mass spectrometry. Over 200 compounds have been annotated; "bile acids, alcohols and derivatives" was the most expressive class in the metabolome of all the species. We successfully discriminated 3 taxonomic groups: 1-tayra (Eira barbara); 2-otters (Lontra longicaudis and Pteronura brasiliensis; 1); and 3-grisons (Galictis vittata and Galictis cuja). Several compounds seemed to be associated with food intake and the digestive process, while others were found for the first time in Neotropical mustelids. We concluded that mustelids show high metabolome diversity and that species-specific identification through metabolomic profiles is possible, thus contributing to the development and implementation of additional non-invasive approaches in the study of mustelids.

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Unlike most animals, most bats cannot synthesize vitamin C endogenously. Consequently, this vitamin must be obtained from the diet. Among the bat species, there are several food groups, such as frugivorous, nectarivorous, insectivorous, and hematophagous. In this work, we measured and compared vitamin C levels in different organs of four species of bats, all collected in southern Brazil. When analyzing and comparing the levels of vitamin C in the four bat species, (regardless of the organ), no significant differences were observed. However, when analyzing and comparing the levels of vitamin C in the four organs (regardless of the species), significant differences were observed, with the highest concentrations in the heart, followed by the liver and brain, while the lowest concentration was measured in the kidneys. Additional differences in the levels of Vitamin C were only observed when each organ was analyzed according to the species/diet. These results indicate a high degree of metabolic homeostasis in bats despite the marked difference in the type of diet.

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Abstract Since the beginning of the COVID-19 pandemic, bats are being pointed as responsible for its origin, even without solid scientific evidence. In this opinion piece, we discuss the most updated information on bats and COVID-19 and argue that bats should not be blamed for a disease they are not responsible for. Bats should be seen not as dangerous animals but, instead, as sources of several scientific insights useful for human health.

Resumo Morcegos e COVID-19: vilões ou vítimas? Desde o início da epidemia de COVID-19, morcegos estão sendo apontados como os culpados por sua origem, mesmo sem evidências científicas sólidas que apontem para tal. Neste artigo de opinião trazemos informações atualizadas sobre morcegos e COVID-19 e discutimos porque morcegos não deveriam ser culpados por uma doença pela qual não foram responsáveis. Morcegos não deveriam ser vistos como animais perigosos, mas sim como fontes de várias ideias e abordagens científicas úteis para a saúde humana.

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Atualmente, muitos jardins zoológicos possuem ambientes com maiores dimensões e que suprem de forma mais adequada as necessidades fisiológicas e comportamentais básicas dos animais, quando comparados aos recintos comumente utilizados no passado. Porém, mesmo com tais melhorias, estes ambientes podem apresentar pouco estimulo psicológico aos animais, uma vez que são relativamente menos complexos que ambientes naturais. Tal contexto pode levar a comportamentos que não são naturais da espécie, como também perdas graduais de atenção e da capacidade de busca e resposta a novos estímulos. Dentre os objetivos das técnicas de enriquecimento ambiental (EA) está o aumento do repertório comportamental dos animais cativos, pois estimula a expressão de comportamentos naturais das espécies. Os objetivos deste trabalho foram avaliar o comportamento de indivíduos das espécies Alouatta guariba clamitans e Alouatta caraya em cativeiro, verificando se há alterações comportamentais decorrentes do enriquecimento ambiental e, se dentre os elementos ofertados, alguns são mais atrativos aos animais. Para isso, comparamos o comportamento de dois grupos de bugios em zoológico durante períodos com e sem enriquecimento ambiental, considerando seis diferentes dispositivos de enriquecimento ambiental. Os bugios responderam bem aos estímulos, interagindo com todos os dispositivos apresentados. Apesar disso, não houve alterações significativas nos padrões de atividade durante a fase de EA para nenhum dos grupos. Porém, o comportamento de forrageio aumentou após o uso do EA, indicando que o EA pode ter despertado o interesse em alimentos diferentes do ofertado na dieta regular. Adicionalmente, também foi observada uma curiosidade maior pelos dispositivos que continham alimentos como recompensa. Desta forma, observamos que...(AU)

Currently, many zoos have larger environments which provide adequate physiological care and fulfill behavioral needs of their animals than captive animal enclosures commonly used in the past. However, even with such improvements these environments can still be stressful to animals as they are relatively less complex as compared to wild and contain few stimuli. This may lead to atypical behaviors, apathy and gradual loss of attention and the ability to search for new stimuli. Among the aims of environmental enrichment (EA) techniques is the increase the behavioral repertoire of animals kept in zoos by encouraging the natural behavior of species. The objectives of this study were to evaluate the behavior of captive Alouatta guariba clamitans and Alouatta caraya individuals by observing the behavioral changes resulting from environmental enrichment and, if among the offered elements, some are more attractive to animals. For this, we compared the behavior of two groups of howler monkeys in zoo during periods with and without environmental enrichment, considering six different environmental enrichment devices. Howler monkeys responded well to stimuli by interacting with all devices presented. However, there were not any significant changes in the activity pattern for environmental enrichment for any group. Yet, environmental foraging increased after the use of the enrichment technique, indicating that the animals can be interested in different types of food. In addition, we observed a greater curiosity for devices that give food as reward. Thus, we observed that the environmental enrichment offered to individuals was able to promote positive changes in the routine and behavior of the animals, so it may be indicative of the improvement in animal welfare conditions. Besides, the devices presented may serve as an example of EA techniques to be applied in other captive situations, including rehabilitation of animal specimens that are able to return to nature.(AU)

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Atualmente, muitos jardins zoológicos possuem ambientes com maiores dimensões e que suprem de forma mais adequada as necessidades fisiológicas e comportamentais básicas dos animais, quando comparados aos recintos comumente utilizados no passado. Porém, mesmo com tais melhorias, estes ambientes podem apresentar pouco estimulo psicológico aos animais, uma vez que são relativamente menos complexos que ambientes naturais. Tal contexto pode levar a comportamentos que não são naturais da espécie, como também perdas graduais de atenção e da capacidade de busca e resposta a novos estímulos. Dentre os objetivos das técnicas de enriquecimento ambiental (EA) está o aumento do repertório comportamental dos animais cativos, pois estimula a expressão de comportamentos naturais das espécies. Os objetivos deste trabalho foram avaliar o comportamento de indivíduos das espécies Alouatta guariba clamitans e Alouatta caraya em cativeiro, verificando se há alterações comportamentais decorrentes do enriquecimento ambiental e, se dentre os elementos ofertados, alguns são mais atrativos aos animais. Para isso, comparamos o comportamento de dois grupos de bugios em zoológico durante períodos com e sem enriquecimento ambiental, considerando seis diferentes dispositivos de enriquecimento ambiental. Os bugios responderam bem aos estímulos, interagindo com todos os dispositivos apresentados. Apesar disso, não houve alterações significativas nos padrões de atividade durante a fase de EA para nenhum dos grupos. Porém, o comportamento de forrageio aumentou após o uso do EA, indicando que o EA pode ter despertado o interesse em alimentos diferentes do ofertado na dieta regular. Adicionalmente, também foi observada uma curiosidade maior pelos dispositivos que continham alimentos como recompensa. Desta forma, observamos que...

Currently, many zoos have larger environments which provide adequate physiological care and fulfill behavioral needs of their animals than captive animal enclosures commonly used in the past. However, even with such improvements these environments can still be stressful to animals as they are relatively less complex as compared to wild and contain few stimuli. This may lead to atypical behaviors, apathy and gradual loss of attention and the ability to search for new stimuli. Among the aims of environmental enrichment (EA) techniques is the increase the behavioral repertoire of animals kept in zoos by encouraging the natural behavior of species. The objectives of this study were to evaluate the behavior of captive Alouatta guariba clamitans and Alouatta caraya individuals by observing the behavioral changes resulting from environmental enrichment and, if among the offered elements, some are more attractive to animals. For this, we compared the behavior of two groups of howler monkeys in zoo during periods with and without environmental enrichment, considering six different environmental enrichment devices. Howler monkeys responded well to stimuli by interacting with all devices presented. However, there were not any significant changes in the activity pattern for environmental enrichment for any group. Yet, environmental foraging increased after the use of the enrichment technique, indicating that the animals can be interested in different types of food. In addition, we observed a greater curiosity for devices that give food as reward. Thus, we observed that the environmental enrichment offered to individuals was able to promote positive changes in the routine and behavior of the animals, so it may be indicative of the improvement in animal welfare conditions. Besides, the devices presented may serve as an example of EA techniques to be applied in other captive situations, including rehabilitation of animal specimens that are able to return to nature.

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1. River system dynamics results in ecological heterogeneities that play a central role in maintaining biodiversity in riverine regions. In central Amazonia, large expanses of forest are seasonally flooded by nutrient-rich water (várzea forests) or by nutrient-poor water (igapó forests). Inundation patterns and the nutrient load of floodwaters are perhaps the most important abiotic factors determining spatial ecological variations in lowland Amazonia, and so they are expected to strongly influence the structuring of animal communities. 2. We examined how inundation patterns and water-nutrient load influence the structure of neotropical assemblages of bats, one of the most diverse vertebrate groups in tropical forests. Bat assemblages were sampled with mist nets in central Brazilian Amazonia, across a mosaic of várzea, igapó, and non-flooding nutrient-poor terra firme forests in the low- and high-water seasons. 3. An ordination analysis clearly separated the assemblages of the three forest types, demonstrating the structural relevance of both flooding and floodwater-nutrient load. Flooded forests had lower species richness because of the absence or rarity of species that make roosts out of leaves of understorey plants, and of those that feed on fruits of shrubs. Gleaning insectivores, also partly dependent on the understorey, were less abundant in flooded forests, but aerial insectivores more abundant, presumably because they benefited from a less cluttered foraging environment. These differences suggest that flooding affects bat assemblages mostly because it reduces the availability of niches associated with understorey vegetation, which tends to be sparser in flooded forests. 4. Nutrient-rich várzea forests had a bat biomass twice that of nutrient-poor igapó and unflooded forests. This difference was not only mostly due to a greater overall abundance of bats, but also attributable to a disproportionate higher abundance of large-bodied bat species. 5. We concluded that both flooding and floodwater-nutrient load are very important in the structuring of lowland Amazonian bat assemblages, with inundation mostly constraining the species composition of the assemblages, and water-nutrient load mostly influencing the abundance of species. The distinctiveness of bat assemblages associated with flooding emphasizes the need to preserve inundated forests, which are under particular pressure in Amazonia.

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