Dirofilaria immitis and Onchocercidae spp. in wild felids from Brazil.

Among the species described within the Onchocercidae family, Dirofilaria immitis is regarded as the most common worldwide, causing severe and often fatal conditions in dogs, cats, and occasionally humans. Dirofilaria spp. are vectored by mosquitoes, simulids, and culicoids, with their epidemiology dependent on the geographical distribution of competent vectors. Eight species of Dirofilaria have been reported so far in Brazil, of which six parasitize non-human primates, deer, procyonids, and marsupials. Here, we investigated the occurrence of Onchocercidae in wild felids (i.e., Panthera onca, Puma concolor, Herpailurus yagouaroundi, Leopardus geoffroyi, Leopardus guttulus, Leopardus pardalis, Leopardus wiedii, Leopardus munoai) from different locations in Brazil. Overall, 82 samples (n = 63 blood; n = 19 tissues) were molecularly screened for cytochrome c oxidase subunit-1 (cox1) gene. Four (i.e., 4.8%) wild felid samples were positive, and at BLAST analysis, the obtained sequences showed varying percentage of nucleotide identity with the genera Brugia (i.e., 87-88%), Setaria (i.e., 89%), and D. immitis (i.e., 94.4%). Phylogenetic analyses clustered sequences obtained into three distinct clades, one with D. immitis and the remaining two with other Onchocercidae spp. Data herein obtained highlight the need for a more comprehensive understanding of the diversity and biology of Onchocercidae in South America in order to assess the potential impact that these species may have for domestic and wild animals, as well as humans.

Epidemiological compatibility of Amblyomma sculptum as possible vector and Panthera onca as reservoir of Cytauxzoon spp. in Midwestern Brazil.

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.

Serosurvey of antibodies against zoonotic pathogens in free-ranging wild canids (Cerdocyon thous and Lycalopex gymnocercus) from Southern Brazil.

The expansion of urbanization on natural areas is increasing contact between human populations with wild animals. Wild carnivores can act as sentinel hosts or environmental health indicators. Thus, the aim of this work was to investigate the exposure of two major species of wild canids from Southern Brazil to selected pathogens. For that, we live-trapped free-ranging Cerdocyon thous and Lycalopex gymnocercus in five localities and determined the frequency of animals with antibodies against Toxoplasma gondii, Trypanosoma cruzi, Leishmania infantum, Neospora caninum, and Leptospira spp. Among the canids sampled, 23% (12/52) (95%CI: 13-36%) had antibodies against T. gondii, with titers ranging from 64 to 512. For T. cruzi, 28% (15/52) (95%CI: 18-42%) of sampled canids were seropositive, with titers ranging from 8 to 64. Concerning the protozoan pathogen N. caninum, a total of 5% (3/52) (95%CI: 2-15%) of wild canids had antibodies against it. None of the sampled canids showed the presence of antibodies against L. infantum. On the other hand, 44% (23/52) (95%CI: 31-57%) of the wild canids showed antibodies against Leptospira spp. The set of results presented here, show that free-ranging neotropical wild canids are exposed and have antibodies against to T. gondii, T. cruzi, Leptospira spp., and to a lesser degree to N. caninum. We found no evidence of L. infantum circulation among the studied populations. These results highlight some of the major pathogens which may represent risks for populations of these wild canids. DATA AVAILABILITY STATEMENT: The data that support the findings of this study are available from the corresponding author upon reasonable request.

Ticks, mites, fleas, and vector-borne pathogens in free-ranging neotropical wild felids from southern Brazil.

The study of vectors and vector-borne diseases associated with ectoparasites from free-living Neotropical small wild felids is scarce, and the few existing studies on this theme focused on the genus Panthera, Paleartic species or in captive animals. For this reason, the aim of this study was to identify the diversity of ectoparasites and potentially associated Rickettsia and Bartonella species in free-ranging neotropical wild cats collected in the State of Rio Grande do Sul, southern Brazil. A total of 82 ticks, 10 fleas and 22 mites were collected from 18 Geoffroy's cats (Leopardus geoffroyi), 11 margays (Leopardus wiedii), two southern tiger cats (Leopardus guttulus), two jaguarundis (Herpailurus yagouaroundi), three ocelots (Leopardus pardalis) and two pumas (Puma concolor). We identified four tick species: Rhipicephalus microplus and three species from genus Amblyomma, the most frequent being Amblyomma aureolatum; three flea species corresponding to Ctenocephalides felis, Xenopsylla cheopis, and Pulex irritans; and one mite of genus Eutrombicula. In ectoparasites we found DNA of Rickettsia parkeri and Rickettsia asembonensis in ticks and DNA of Bartonella clarridgeiae, Bartonella sp. and R. asembonensis in fleas. Our results highlight the evidences of vectors and vector-borne agents in wild animals, and their potential wide distribution in the Pampa biome and the southernmost portion of the Atlantic Rainforest in Brazil.

Molecular and Serological Survey of the Cat-Scratch Disease Agent (Bartonella henselae) in Free-Ranging Leopardus geoffroyi and Leopardus wiedii (Carnivora: Felidae) From Pampa Biome, Brazil.

The genus Bartonella comprises emerging bacteria that affect humans and other mammals worldwide. Felids represent an important reservoir for several Bartonella species. Domestic cats are the main reservoir of Bartonella henselae, the agent of cat scratch disease (CSD). It can be transmitted directly by scratches and bites from infected cats and via cat fleas. This study aims to investigate the circulation of Bartonella spp. in free-ranging Neotropical wild felids from Southern Brazil using serological and molecular methods. In this study, 53 live-trapped free-ranging wild felids were sampled, 39 Leopardus geoffroyi and 14 Leopardus wiedii, from five municipalities in the Rio Grande, do Sul state, southern Brazil. All captured animals were clinically healthy. Two blood samples of L. geoffroyi were positive, by PCR, for the presence of B. henselae DNA. Conversely, none of L. wiedii blood samples were positive when tested using PCR. Indirect immunofluorescence assay (IFA) showed that 28% of serum samples of wild felids were reactive (seropositive) for B. henselae by immunofluorescence, with titers ranging from 64 to 256. The results presented here provide the first evidence of a Bartonella-enzootic cycle involving L. geoffroyi and L. wiedii, which may account for the spillover of the emerging zoonotic pathogen B. henselae for the indigenous fauna in Southern Brazil.

Multidrug Resistance in Enterococci Isolated From Wild Pampas Foxes (Lycalopex gymnocercus) and Geoffroy's Cats (Leopardus geoffroyi) in the Brazilian Pampa Biome.

Enterococci are ubiquitous microorganisms present in various environments and within the gastrointestinal tracts of humans and other animals. Notably, fecal enterococci are suitable indicators for monitoring antimicrobial resistance dissemination. Resistant bacterial strains recovered from the fecal samples of wild animals can highlight important aspects of environmental disturbances. In this report, we investigated antimicrobial susceptibility as well as resistance and virulence genes in fecal enterococci isolated from wild Pampas foxes (Lycalopex gymnocercus) (n = 5) and Geoffroy's cats (Leopardus geoffroyi) (n = 4) in the Brazilian Pampa biome. Enterococci were isolated from eight out of nine fecal samples and Enterococcus faecalis was identified in both animals. However, E. faecium and E. durans were only detected in Pampas foxes, while E. hirae was only detected in Geoffroy's cats. Antimicrobial susceptibility analysis showed resistance to rifampicin (94%), erythromycin (72.6%), ciprofloxacin/norfloxacin (40%), streptomycin (38%), and tetracycline (26%). The high frequency of multidrug-resistant enterococci (66%) isolated in this study is a matter of concern since these are wild animals with no history of therapeutic antibiotic exposure. The tetM/tetL and msrC/ermB genes were detected in most tetracycline- and erythromycin-resistant enterococci, respectively. The gelE, ace, agg, esp, and clyA virulence genes were also detected in enterococci. In conclusion, our data suggest that habitat fragmentation and anthropogenic activities in the Pampa biome may contribute to high frequencies of multidrug-resistant enterococci in the gut communities of wild Pampas foxes and Geoffroy's cats. To the best of the authors' knowledge, this is the first report of antimicrobial-resistant enterococci in the Pampa biome.

Detection of Rangelia vitalii (Piroplasmida: Babesiidae) in asymptomatic free-ranging wild canids from the Pampa biome, Brazil.

Canine rangeliosis is a tick-borne disease caused by the protozoan Rangelia vitalii, which has only been reported in South America. With this knowledge, we hypothesized that neotropical foxes could act as asymptomatic natural carriers of R. vitalii. To test this, we captured 44 free-ranging foxes and investigated the presence of R. vitalii DNA, and whether the infected animals presented any clinical findings or hematological changes. Eight foxes (18%), seven Cerdocyon thous (7/27-25%), and one Lycalopex gymnocercus (1/17-5%) were positive for R. vitalii. All foxes were clinically healthy and showed no hematological abnormalities. Thus, we propose that neotropical canids, particularly C. thous, could be the natural carriers of R. vitalii.

Trophic ecology of sympatric small cats in the Brazilian Pampa.

Information about resource partitioning among small cat species that live in sympatry in South America is fairly incomplete. Knowledge about feeding habits is essential for understanding the role of these predators in the environment, the impact on prey populations, and potential competition among themselves and with other carnivores. This study aimed to describe and compare the diet of four sympatric small cats in the grasslands of southern Brazil. We analysed the stomach contents of 37 Geoffroy's cats (Leopardus geoffroyi), 27 margays (Leopardus wiedii), 14 pampas cats (Leopardus colocola), and 20 jaguarundis (Herpailurus yagouaroundi) obtained as road kill in the Brazilian Pampa in southern Brazil. Small mammals were the most representative class consumed by all cats, followed by Aves, Reptilia, and Amphibia. Some items, such as rodents Cavia aperea, Akodon sp., Oligoryzomys sp. and Passeriformes were consumed by all cat species. Niche overlap varied widely, from 10% (margay x jaguarundi) to 92% (jaguarundi x pampas cat). Niche breadth indicated that jaguarundi were the most specialized of the cats (Bsta = 0.24) in this region, with a diet closely associated to C. aperea. Margay consumed more items associated with arboreal behaviour than other cat species, but consumed more terrestrial items than arboreal ones. The pampas cat consumed mostly terrestrial species associated with open fields. Geoffroy's cat consumed mammals found in a diversity of habitats, indicating high ecological flexibility. Species with more similarity in diet such as jaguarundi and pampas cat probably present temporal segregation in activity. In conclusion, despite their habitat and diet similarities, these four species explore distinct microhabitats by foraging different prey groups, what favor them to live in sympatry.

Molecular phylogenetic position of endangered Wilfredomys within Sigmodontinae (Cricetidae) based on mitochondrial and nuclear DNA sequences and comments on Wiedomyini.

Wilfredomys, a monotypic genus of endangered sigmodontine rats, was historically related to the tribe Thomasomyini or considered "incertae sedis". Given no molecular data is available for Wilfredomys, the phylogenetic position of this taxon is uncertain in relation to modern, molecular hypotheses of sigmodontine relationships. We investigate the phylogeny of Wilfredomys to provide a hypothesis of its position within Sigmodontinae based on nuclear and mitochondrial DNA sequences. Bayesian and maximum likelihood phylogenetic analyses recovered Wilfredomys oenax as sister to Wiedomys pyrrhorhinos, and Wie. cerradensis fell out sister to this clade. At the genus level, Phaenomys is sister to Wilfredomys + Wiedomys, forming a novel and well-supported sigmodontine clade. Our results suggest that tribe Wiedomyini should encompass Wilfredomys in addition to Wiedomys and Cholomys, thus the hypothesis that Wiedomys is paraphyletic should be investigated further. Another plausible classification scheme consistent with our results would be to expand Wiedomyini to encompass the clade composed of Phaenomys + Wilfredomys + Wiedomys. Last, our recovery of an "Atlantic clade" composed of lineages restricted to eastern South America supports the idea that this region has likely played an important role in sigmodontine diversification.