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Background: The proximity between people and their domestic animals with wild animal populations can result in the spread of diseases with a significant impact on public health. Infection by parasites in wildlife is considered an important bioindicator of the current state of ecosystems, and studying the epidemiology of these infections is essential for a better understanding of natural foci. However, research on parasites in southern Brazil, especially in Rio Grande do Sul (RS), is considered incipient. Therefore, in this study, we aimed to identify the parasitic fauna of wild animals in the southern region of RS through fecal parasitological diagnosis. We processed 82 fecal samples from wild animals - including birds, mammals, and reptiles - from cities within the microregion of Pelotas, using the Zinc Sulfate Centrifugal Flotation, Spontaneous Sedimentation and Oocyst Sporulation techniques., Results: In 69.5% of the samples (93.1% of mammals, 47% of birds and 50% of reptiles), we found helminth eggs and/or protozoan cysts/oocysts, with strongylid-type eggs being the most frequent parasites (44.11%). Additionally, 64.9% of the positive samples were parasitized by at least one morphogroup with zoonotic agents (Taeniidae, Capillaria, Strongyloides, Spirometra, Lagochilascaris, Sarcocystis, Trichuris, Giardia, Ancilostomid, Physaloptera, Toxocara, Fasciola). We also recorded the first finding of Monocystis spp. in a Southern tamandua (Tamandua tetradactyla)., Conclusions: Thus, it was observed that the majority of the animals were parasitized and, consequently, susceptible to a wide range of pathogens of medical and veterinary interest, highlighting the importance of these hosts in the spread of parasites, especially those with zoonotic potential. However, the ecology of transmission and the role of these hosts in the life cycles of parasites should be further explored in other studies., Competing Interests: Declarations. Ethics approval and consent to participate: This work was approved by the Ethics Committee on the Use of Animals at UFPel (process number 23110.046990/2022-02). Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)

Metals and metalloids are persistent environmental pollutants with the potential for bioaccumulation, posing significant health risks, including genotoxicity. These contaminants are prevalent in industrial and agricultural runoff. This study utilizes Trachemys dorbigni, an aquatic reptile, as a bioindicator to assess environmental contamination by metals and metalloids in both rural and urban settings in Pelotas, Rio Grande do Sul, Brazil. We captured specimens using pit-type traps with barriers (fyke nets), dividing them into two groups: 15 from a rural area and 15 from an urban area. Each animal underwent physical evaluations, and biometric data (weight, total carapace length and width) were recorded to calculate body condition indices. Biological samples were collected via manual restraint, with blood samples drawn from the supraoccipital venous sinus and linear carapace fragments obtained through manual scraping. Water samples from each location were also analyzed. Using atomic absorption spectrophotometry, concentrations of Al, As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb and Zn were measured in the water, carapace fragments, and blood samples. Cellular damage was assessed through flow cytometry and microscopy, examining erythrocyte disruption, reactive oxygen species, membrane fluidity, DNA fragmentation and micronucleus formation. Urban area samples showed concentrations of As, Cd, Cu, Fe, Hg and Ni exceeding national standards set by the Conselho Nacional do Meio Ambiente (CONAMA), with rural areas also showing elevated levels of As, Cd, Hg and Ni. Biometric analysis revealed that rural reptiles had significantly higher weight and carapace dimensions, whereas urban tortoises displayed a higher body condition index and significantly elevated blood levels of Al, Cr, Ni, Pb and Zn. The urban tortoises also exhibited higher concentrations of all tested metal(loid) in carapace samples (p < 0.05) and more pronounced cellular damage (p < 0.05), highlighting severe bioaccumulation and associated deleterious effects. Elevated reactive oxygen species levels were noted in rural specimens. This study underscores the impact of water degradation and metal(loid) pollution in urban environments on T. dorbigni, suggesting that carapace tissue analysis can serve as a chronic exposure indicator to these harmful contaminants., Competing Interests: Declarations Conflict of interest The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Phalacrocorax brasilianus (Gmelin, 1789) (Aves: Phalacrocoracidae) is one of the few piscivorous birds inhabiting freshwater and saline environments, being considered one of the most abundant aquatic species in Rio Grande do Sul, Brazil, especially along the state's coastline. It is known that birds are hosts to a wide variety of disease-causing agents, among them, nematodes of the Contracaecum (Anisakidae) have a large number of recognized species. However, little is still known about the occurrence of these parasites in the Southern region of Brazil. Herein we identified for the first time Contracaecum australe Garbin, Mattiucci, Paoletti, González-Acuña, and Nascetti, 2011 (Nematoda: Anisakidae) parasitizing P. brasilianus in Southern Brazil. Nematodes found in the bird's proventriculus were subjected to morphometric analyses, by optical microscopy and scanning electron microscopy, and molecular analyses. Molecular phylogeny based on the analysis of the 18S, ITS-1, 5.8S and ITS-2 genes showed our sequences identical to those of C. australe. Therefore, this is the first record of C. australe in southern Brazil, expanding the geographical distribution of the parasite species in the country. Additionally, new molecular sequences are being provided, contributing to the knowledge of Contracaecum species parasitizing cormorants., Competing Interests: Declaration of competing interest The authors declare that there is no conflict of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The present study aimed to report the morphometric and hematological indices and genotoxicity of a free-life population of D'Orbigny's slider turtles (Trachemys dorbigni) living in an urban area in Southern Brazil. For that, 16 specimens were randomly captured in an urban canal that receives irregular releases of wastewater. Biometrics and external visual changes were analyzed, such as turtle shell deformities, and the presence of parasites. Blood samples were collected to evaluate the hematological profile and the presence of micronuclei and other erythrocyte nuclear abnormalities as potential mutagenic and genotoxic effects. Water physicochemical parameters were also measured. Organisms with ectoparasites (31.25%) and small carapace deformations (56.25%) were observed, but maximum carapace length and weight were considered normal for the species according to the literature. The blood profile indicated low hemoglobin and hematocrit and a high number of total leukocytes, particularly eosinophils which characterize parasitic infections. A frequency of 0.12% for the micronucleus was considered basal, but the frequency of other erythrocyte abnormalities was evident, mainly of blebbed nuclei (63.79%), indicating chromosomal damage in the early stage. The results of this study suggest that natural populations of chelonian inhabiting urbanized areas are impacted by anthropogenic activities in the surrounding environment. Furthermore, it provides comprehensive data which can serve as a comparative model for environmental monitoring studies involving turtles., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Rangeliosis, caused by protozoan Rangelia vitalii, is transmitted by the tick Amblyomma aureolatum. The disease is characterized by hemolytic and hemorrhagic disorder and has been described in dogs and other wild canids. The aim of this study was to compare clinicopathological findings and laboratory results of a Rangelia infection in a crab-eating fox (Cerdocyon thous) with those of canine rangeliosis. The zoo of Universidade de Caxias do Sul, received a crab-eating fox with marked jaundice in mucous membranes, dark-colored stools and neurological signs. The animal underwent an ear tip smear examination and blood collection for complete blood counts, serum biochemistry and PCR. Free-living and intraerythrocytic pyriform structures consistent with R. vitalii were found in the blood smear of the ear tip. The erythrogram revealed normocytic normochromic anemia, moderate macrocytosis, polychromasia and metarubricytosis. The leukogram revealed leukocytosis with neutrophilia and monocytosis, as well as severe thrombocytopenia. Serum biochemistry showed hypoproteinemia, hypoalbuminemia and elevated levels of urea and creatinine. The treatment was performed with imidocarb hydrochloride and dexamethasone, however 24 h after initiation of treatment the animal died. Macroscopic examination revealed jaundice, subcutaneous edema, enlarged superficial lymph nodes, splenomegaly, and hemorrhage of internal organs. Histological sections of the cerebellum, lung, pancreas, intestine and heart were consistent with R. vitalii infection of the vascular endothelium. Pathological and hematological findings were similar to those found in infected dogs, with clinical presentation characterized by hemolytic anemia and hemorrhage. The description of this case showed that C. thous does not only serve as reservoir of R. vitalii but may also develop disease., (Copyright © 2019 Elsevier GmbH. All rights reserved.)

Rangelia vitalii is the etiologic agent of canine rangeliosis, a severe piroplasmosis that affects domestic dogs in Brazil, Uruguay and Argentina. While R. vitalii is one of the most pathogenic tick-borne pathogens for dogs in the world, its tick vector has remained unknown. The present study evaluated the vector competence of Rhipicephalus sanguineus sensu lato (both tropical and temperate species), Amblyomma aureolatum, Amblyomma ovale, Amblyomma tigrinum, and Amblyomma sculptum for R. vitalii. These six tick species were selected for the study because they comprise the main tick species infesting dogs within the distribution area of canine rangeliosis in South America. Acquisition feeding of the above six tick species was performed on domestic dogs showing clinical signs of canine rangeliosis, after being experimentally infected through intravenous inoculation or infestation with R. vitalii-infected ticks. Thereafter, engorged ticks were evaluated for transstadial and transovarial passages of R. vitalii through molecular analysis after molting or oviposition and egg hatching. The resultant ticks were evaluated for their competence to transmit R. vitalii to susceptible dogs. Among the six tick species, only A. aureolatum was able to acquire and perpetuate R. vitalii by transstadial and transovarial passages, as demonstrated by >5% infection rates of ticks after hatching or molting. When exposed to transmission feeding, only A. aureolatum ticks were competent to transmit R. vitalii to dogs, which became severely ill, and the results confirmed by molecular methods and blood smear examination to have acquired rangeliosis. Results of the present study, coupled with epidemiological data, indicate that A. aureolatum is a natural vector of R. vitalii. Our results also indicate that R. vitalii is the first Piroplasmorida agent to be transovarially transmitted in Amblyomma ticks., (Copyright © 2018 Elsevier GmbH. All rights reserved.)

Canine rangeliosis (popular names: "nambi-uvú", i.e. ``bleeding ears''; "peste de sangue", i.e. ``bleeding plague''; and "febre amarela dos cães", i.e. ``yellow fever of dogs'') is a tick-borne haemolytic and haemorrhagic disease caused by the protozoan parasite Rangelia vitalii which infects erythrocytes, leukocytes, and endothelial cells of blood capillaries. Rangelia vitalii was first reported as a novel piroplasm of dogs in 1910 in Brazil, a discovery that was met with skepticism at that time. Canine rangeliosis has been diagnosed in domestic dogs not only in Brazil but also in other South American countries (Argentina and Uruguay). Rangelia vitalii infection has also been found incidentally in Brazil in wild dogs (Cerdocyon thous, the crab-eating fox). Despite the fact that researchers in the early 1900s suggested that R. vitalii was a hitherto unidentified piroplasm that would be transmitted by the tick Amblyomma aureolatum, it was not until 2012 that these hypotheses were actually confirmed by PCR and transmission studies. Molecular studies have shown that R. vitalii is related to the Babesia sensu strictu clade, but genetically different from other morphologically similar species of Babesia that infect dogs. Another difference between Babesia spp. and R. vitalii is the ability of R. vitalii to invade endothelial cells, erythrocytes, and leukocytes. Experimental infection in dogs has successfully reproduced the clinical picture and pathology of the natural disease. In this article, epidemiology, clinical signs, laboratory findings, pathogenetic mechanisms including oxidative stress and immune response, necropsy findings, microscopic lesions, diagnosis, and treatment of canine rangeliosis are reviewed. What is currently known about this protozoal disease since its first report over a century ago is presented herein., (Copyright © 2014 Elsevier GmbH. All rights reserved.)

Rangeliosis is a hemoparasitosis that affects dogs in Brazil. The disease has similar clinical and pathological characteristics to other hemo-protozoan infections. So, this paper has aimed to report a clinical case of infection by Rangelia vitalii in one dog, focusing on the need for the differential diagnosis to other infectious diseases. The animal showed apathy, anemia, thrombocytopenia, alteration of leucogram, and bleeding. The first difference was the observation of parasites in blood smears, where R. vitalii was visualized within leukocytes and erythrocytes. The confirmation of the clinical diagnosis was made by molecular test to R. vitalii. The dog was debilitated, and died a few hours after treatment at the veterinary hospital. At necropsy, splenomegaly, lymphadenopathy, and mild jaundice in the abdominal viscera were found. This article draws attention to the need for the parasitological, serological, and molecular to differential diagnosis in order to differentiate from other clinically similar disorders.

Rangeliosis is a disease which affects dogs in Brazil, caused by a piroplasm known as Rangelia vitalii. This disease causes a lot of clinico-pathological features, including the coagulation disorders associated with bleeding. The cause of these changes has not yet been determined. Considering the association of purinergic system and hemostasis this study aimed to evaluate the activity of enzymes that hydrolyze ATP, ADP and AMP; and deamination of adenosine in platelets from dogs experimentally infected with R. vitalii. For this study, 12 healthy young dogs (females) were used, separated in two groups. Group A (n=5) were uninfected controls, and group B were experimentally infected with R. vitalii (n=7). After being inoculated with R. vitalii-infected blood, animals were monitored by blood smear examinations, which showed intra-erythrocytic forms of the parasite after five days post-inoculation (PI). Blood samples were collected to quantitate and separate platelets (Day 0, 12 and 21 PI) and to measure the enzymatic activities (Day 12 and 21 PI). The activity of NTPDase, 5'-nucleotidase and adenosine deaminase (ADA) was measured in platelets. A reduction (P<0.01) in the number of platelets was observed in R. vitalii-infected blood at Days 12 and 21 PI. At Day 12 PI, a reduction (P<0.01) in the hydrolysis of ATP, ADP and AMP, and deamination of adenosine was observed in dogs infected with R. vitalii. At Day 21 PI the ADA activity remained decreased, unlike the activity of NTPDase which increased (P<0.05). Based on these results we can conclude that ATP, ADP and AMP hydrolysis and adenosine deamination were altered in platelets of R. vitalii-infected dogs. Considering the importance of the purinergic system in hemostasis, it is believed that those changes contribute to the coagulation disorders and bleeding observed in R. vitalii-infected dogs and discussed in this manuscript., (Copyright © 2012 Elsevier Inc. All rights reserved.)

In the beginning of the 20th century, a new canine disease was reported in Brazil under the name "nambiuvú", whose etiological agent was called Rangelia vitalii, a distinct piroplasm that was shown to parasitize not only erythrocytes, but also leucocytes and endothelial cells. In this new century, more publications on R. vitalii were reported from Brazil, including an extensive study on its ultrastructural analysis, in addition to clinical, pathological, and epidemiological data on nambiuvú. However, a molecular analysis of R. vitalii has not been performed to date. In the present study, we performed molecular phylogenetic analyses of R. vitalii based on fragments of the genes 18S rRNA and the heat shock protein 70 (hsp70), amplified by PCR performed on blood samples derived from five clinical cases of dogs presumably infected with R. vitalii in southern Brazil. In addition, we examined Giemsa-stained thin blood smears from these same dogs. DNA sequences (604-bp) of the 18S rRNA gene obtained from the five dogs were identical to each other, and by Blast analysis, this sequence shared the highest degree of sequence identity (95%) with Babesia sp. China-BQ1. DNA sequences (1056-bp) of the hsp70 gene obtained from the five dogs were identical to each other, and by Blast analysis, this sequence shared the highest degree of sequence identity (87%) with Babesia bigemina. Phylogenetic analyses inferred from either of the two genes resulted in the newly genotype being placed in the Babesia spp. sensu stricto clade with very high bootstrap support (95-100%) in three analyses (Neighbor-Joining, Maximum parsimony, and Maximum likelihood). Giemsa-stained thin blood smears from the dogs were shown to contain piroplasm organisms within erythrocytes, monocytes and neutrophils (individual forms), and schizont-like forms within neutrophils, in accordance with literature reports of R. vitalii. Based on these results, we conclude that R. vitalii, the etiological agent of "nambiuvú" in southern Brazil, is a valid species of piroplasm. Further studies are required to evaluate the validity of the genus Rangelia., (Copyright © 2011 Elsevier B.V. All rights reserved.)

In this study, we reported the first outbreak of the infection by Trypanosoma vivax in horses in southern Brazil, a non-endemic region where bovines have only recently been found infected by this trypanosome species. We evaluated 12 horses from a farm in southern Brazil, where four horses displayed pale mucous membranes, fever, weight loss, and swelling of abdomen, prepuce, or vulva. The diagnosis of T. vivax was confirmed in four horses by morphological parameters of trypomastigotes in blood smears and species-specific PCR. All T. vivax-infected animals showed anemia, and most showed increased levels of beta-1, beta-2, and gamma globulins. Horses were treated with diminazene aceturate, but cure was not achieved, and the disease relapsed after therapy. These findings demonstrated that Brazilian T. vivax isolates, which were already reported infecting cattle, buffaloes, goats, and sheep, can be highly pathogenic for horses, causing severe disease and even death of the animals due to the recurrence of the infection.