Parasitological assessment of wild ring-tailed coatis (Nasua nasua) from the Brazilian Atlantic rainforest

Description of the parasitic fauna of a specimen of Didelphis albiventris at Rio Grande do Sul

Didelphis albiventris is considered the most common marsupial in Rio Grande do Sul. With omnivorous and synanthropic habits, it can serve as a host to various parasites, playing an important role in maintaining their biological cycle. Despite being a widespread and abundant species, it has a relatively little-known parasitic fauna. Therefore, the aim of this study was to report the diversity of parasites in a fecal sample from D. albiventris in Rio Grande do Sul, Southern Brazil. Modified Centrifugal-flotation and Spontaneous sedimentation techniques were used, revealing a high taxonomic diversity of parasites. Eggs of Ancylostoma spp., Toxocara spp., and Anoplocephalidae were reported for the first time in the host in the southern region of the country, along with the first report of pseudoparasitism by Syphacia spp. and Monocystis spp. in this animal species. The presence of different parasites in the feces of D. albiventris is of utmost importance, primarily for public health, but also for understanding the biodiversity of parasites present in wildlife, which has been poorly studied until now. This allows the implementation of effective strategies for controlling, preventing and treating these diseases.

Gongylonema sp. in the Tongue of a Brown-Nosed Coati (Nasua nasua) from the Brazilian Atlantic Forest

Two parasites were collected from the epithelial layer of the tongue mucosa of a brown-nosed coati (Nasua nasua) in an area of Atlantic Forest in Minas Gerais State, Brazil. These were identified as female Gongylonema sp. nematodes, not previously reported in Brazilian wild carnivores.

Parasitic infections, hematological and biochemical parameters suggest appropriate health status of wild coati populations in anthropic Atlantic Forest remnants

Coatis are hosts of a great diversity of parasites, that due to anthropic pressures in forest fragments, like changes in landscapes and ecosystems, can influence the dynamics and physiological responses to those parasite infections, affecting the animal's health and fitness. This is the first study about health parameters and parasitic infections of wild coati (Nasua nasua) populations in the Atlantic Forest (Pernambuco Center of Endemism). The following hypotheses were evaluated: (i) infections and co-infections by gastrointestinal parasites and ectoparasites can generate changes in the health parameters of coatis such as the body condition score (BCS), packed cell volume (PCV), leukogram, and serum protein profile; (ii) biological aspects (sex and age) or fragment they inhabit, can influence changes in the health parameters (BCS, PCV, leukogram and serum protein profile). Were studied 55 free-living coatis in three anthropized forest remnants in the Metropolitan Region of Recife. After chemical containment, the animals were submitted to physical examination and collection of biological samples (blood, feces, and ectoparasites). On the physical examination, 23.6% of coatis had a low BCS and 5.4% were overweighted. Amblyomma spp. ticks were found in 83.6% of the animals of all studied remnants, A. sculptumAmblyomma sculptum in 12.7% and A. ovale in 1.8%. Regarding gastrointestinal parasites, Ancylostoma sp. was the most prevalent (80.4%) and most animals (66.7%) had co-infection with Ancylostoma sp. and Capillaria sp., Strongyloides sp., Acanthocephala, Cestoda, and Coccidia. The 76.5% of the coatis presented co-infections with Ancylostoma spp. + Amblyomma spp. Principal coordinates analyses (PCoA) scores of health parameters were used as dependent variables and fragment, sex, age, Ancylostoma sp. infection, gastrointestinal parasites co-infection, Amblyomma spp. infestation and co-infection of Ancylostoma sp. + Amblyomma spp. as a predictor variable in the linear models. Parasites did not influence the PCV of the individuals, but a decrease was evident in adult animals. Variations in protein profile, neutrophils, and lymphocytes, without leaving the normal range for the species, but WBC were predicted by age group, and infections by Ancylostoma or Amblyomma spp., but not their co-infections. The free-living coati populations of the anthropized remnants in the Atlantic Forest of northeastern Brazil proved to be healthy and seem to be adapted to face the challenges of anthropization and parasitic infections.

Machine learning-based analyses support the existence of species complexes for Strongyloides fuelleborni and Strongyloides stercoralis

Human strongyloidiasis is a serious disease mostly attributable to Strongyloides stercoralis and to a lesser extent Strongyloides fuelleborni, a parasite mainly of non-human primates. The role of animals as reservoirs of human-infecting Strongyloides is ill-defined, and whether dogs are a source of human infection is debated. Published multi-locus sequence typing (MLST) studies attempt to elucidate relationships between Strongyloides genotypes, hosts, and distributions, but typically examine relatively few worms, making it difficult to identify population-level trends. Combining MLST data from multiple studies is often impractical because they examine different combinations of loci, eliminating phylogeny as a means of examining these data collectively unless hundreds of specimens are excluded. A recently-described machine learning approach that facilitates clustering of MLST data may offer a solution, even for datasets that include specimens sequenced at different combinations of loci. By clustering various MLST datasets as one using this procedure, we sought to uncover associations among genotype, geography, and hosts that remained elusive when examining datasets individually. Multiple datasets comprising hundreds of S. stercoralis and S. fuelleborni individuals were combined and clustered. Our results suggest that the commonly proposed 'two lineage' population structure of S. stercoralis (where lineage A infects humans and dogs, lineage B only dogs) is an over-simplification. Instead, S. stercoralis seemingly represents a species complex, including two distinct populations over-represented in dogs, and other populations vastly more common in humans. A distinction between African and Asian S. fuelleborni is also supported here, emphasizing the need for further resolving these taxonomic relationships through modern investigations.