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Cytauxzoonosis is an acute and highly lethal tick-borne disease of wild and domestic cats, and is widely distributed in Africa, Asia, Europe, the USA and Brazil. So far, only two tick species present on the USA are experimentally confirmed in Cytauxzoon transmission however, in Brazil and other continents, the epidemiology of the disease remains unknown. Evidences points to Panthera onca as a possible reservoir, but there is no evidence to point the vector. Therefore, this study evaluates the presence of Cytauxzoon spp. in wild felids from areas with and without records of Amblyomma sculptum this ixodid for comparison. Overall, 53 blood samples of P. onca, Puma concolor, and Leopardus pardalis from the Midwest region (MR; region with A. sculptum) and 143 blood and/or spleen samples from Leopardus geoffroyi, Leopardus wiedii, Leopardus munoai, Leopardus guttulus, Herpailurus yagouaroundi, L. pardalis, and P. concolor from Rio Grande do Sul State (RS; without A. sculptum). Only one feline sample was negative for Cytauxzoon sp. from MR; no samples from RS were positive. In total, 507 ticks were identified from MR felids, with predominance of A. sculptum (69.23%). In RS, there were 93 ixodids, of which 90.32% were Amblyomma aureolatum. The difference in the tick fauna of the two regions studied (presence/absence of A. sculptum) reflects the results found. This study highlighted A. sculptum as a possible vector since this hemoparasite was abundantly observed in areas where it occurs, also, there was no evidence of Cytauxzoon spp. where it was absent. Additionally, the study supported the suggestion that P. onca is the reservoir for the agent in MR., Competing Interests: Declaration of Competing Interest None., (Copyright © 2022 Elsevier GmbH. All rights reserved.)

The objective of this study was to determine the structure of the helminth fauna and identify the macroscopic and histopathological alterations associated with parasitic infections in Phrynops geoffroanus. Freshwater turtles of both sexes were captured during the dry and rainy seasons in four municipalities along the Capibaribe River. The study included 63 animals, of which 79.37% (50/63) were parasitized by one or more helminths. In total, 933 helminths of seven taxa were recovered: Serpinema monospiculatus, Spiroxys figueiredoi, Nematophila grandis, Polystomoides brasiliensis, Cheloniodiplostomum testudinis, Telorchis birabeni, and Prionosomoides scalaris. Monogeneans and digenetic trematodes were more sensitive to environmental pressures, since the prevalences varied significantly between areas. Nematodes proved to be more resistant to environmental pressure and caused severe injuries to their hosts: nodules in the stomach and small intestine, adhesions in the liver capsule, and pulmonary emphysema. Parasitic granulomas were recorded at the infection sites and in the lungs and liver, the latter caused by migration of S. figueiredoi larvae. This is the first record of P. brasiliensis, N. grandis, C. testudinis, and T. birabeni parasitizing P. geoffroanus in the state of Pernambuco. Histopathology proved to be an important tool for studies on the impact of parasites at the individual, population, and ecosystem levels. Considering the use of the Capibaribe River for public water supply, fishing, and other activities, within the One Health perspective, this study demonstrates that the anthropogenic impact affects parasites and their hosts, in addition to the human population that uses this ecosystem., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Snakebite envenoming is the cause of an ongoing health crisis in several regions of the world, particularly in tropical and neotropical countries. This scenario creates an urgent necessity for new practical solutions to address the limitations of current therapies. The current study investigated the isolation, phytochemical characterization, and myotoxicity inhibition mechanism of gallic acid (GA), a myotoxin inhibitor obtained from Anacardium humile. The identification and isolation of GA was achieved by employing analytical chromatographic separation, which exhibited a compound with retention time and nuclear magnetic resonance spectra compatible with GA's commercial standard and data from the literature. GA alone was able to inhibit the myotoxic activity induced by the crude venom of Bothrops jararacussu and its two main myotoxins, BthTX-I and BthTX-II. Circular dichroism (CD), fluorescence spectroscopy (FS), dynamic light scattering (DLS), and interaction studies by molecular docking suggested that GA forms a complex with BthTX-I and II. Surface plasmon resonance (SPR) kinetics assays showed that GA has a high affinity for BthTX-I with a K D of 9.146 × 10 -7  M. Taken together, the two-state reaction mode of GA binding to BthTX-I, and CD, FS and DLS assays, suggest that GA is able to induce oligomerization and secondary structure changes for BthTX-I and -II. GA and other tannins have been shown to be effective inhibitors of snake venoms' toxic effects, and herein we demonstrated GA's ability to bind to and inhibit a snake venom PLA 2 , thus proposing a new mechanism of PLA 2 inhibition, and presenting more evidence of GA's potential as an antivenom compound., (Copyright © 2021. Published by Elsevier B.V.)

The objective of this study was to report, for the first time, the presence of an invasive coral (Tubastraea tagusensis) in an oil platform on the Brazilian equatorial continental shelf. This structure is located more than 1200 km north from other oil and gas structures colonized by this coral. We also discussed the retirement and decommissioning of old biofouling-encrusted oil and gas platforms (~62 platforms) from decreased production and the current oil crisis, exacerbated by the COVID-19 pandemic. This presents an ecological concern due invasive coral range expansion and potential impacts to poorly studied ecosystems such as marginal shallow-water coral reefs and mesophotic ecosystems. It is imperative that mindful risk analysis and rigorous environmental studies must precede the installation of new oil and gas platforms. In addition, decommissioning of retired structures should take into consideration marine restoration and non-indigenous species dispersal, and more specifically, Tubastraea bioinvasion., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Parasites may influence host fitness and consequently exert a selective pressure on distinct phenotypes of the host population. This pressure can result in an evolutionary response, maintaining only individuals with certain traits in the population. The present study was aimed at identifying the morphological characteristics of juveniles and adults of Columba livia that may influence the distribution patterns of lice, Pseudolynchia canariensis and Haemoproteus columbae and how the populations of these parasites vary throughout the seasons of the year. Between July 2012 and July 2014, 377 specimens of C. livia were captured. We observed a significant increase in the mean intensities of infestation by pigeon flies and lice, as well as in species richness of ectoparasites during the warmest seasons, suggesting a reproductive synchrony between ectoparasites and host species. Bill length, body mass, and body length did not affect the infestation levels of ectoparasites on adults and juveniles of C. livia with three distinct plumage colors. In juveniles, plumage color affected only the mean intensity of infestation by lice, with Spread individuals as the most infested. This indicates that melanin in feathers was not an effective barrier against ectoparasites., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Seaweed species from a coastal area contaminated by heavy metals (Sepetiba Bay) in Rio de Janeiro State (Brazil) presented different levels of Zn concentrations. In some species the levels were 20 times higher than that from a noncontaminated area. The present study was undertaken to investigate the capability of different species to tolerate and accumulate zinc. For this purpose six species, Ulva lactuca, Enteromorpha flexuosa, Padina gymnospora, Sargassum filipendula, Hypnea musciformis, and Spyridia filamentosa, were cultivated under laboratory semistatic conditions in five Zn concentrations in seawater, 10, 20, 100, 1000, and 5000 micrograms.liter-1 for a period of 21 days. All species died at 5000 micrograms.liter-1 of Zn, two species (U. lactuca and E. flexuosa) died at 1000 micrograms.liter-1, and one, H. musciformis, died with 100 micrograms.liter-1. The lowest concentration of Zn that presented growth inhibition in the six species was 20 micrograms.liter-1. The brown alga P. gymnospora presented the highest accumulation level of Zn, and H. musciformis the lowest level. The results of tolerance and accumulation under laboratory conditions, associated with field results, indicate the species of Padina and Sargassum as the best species for monitoring heavy metals in tropical coastal areas, and the potential use of their biomass to remove heavy metals from wastewaters.