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Goats are the one of the most susceptible domestic species to toxoplasmosis affecting animal health and production. The present study aimed to determine the seroprevalence of T. gondii infection in dairy goats from Rio de Janeiro, Brazil, as well as to evaluate associated risk factors, parasitic DNA detection in raw goat milk samples, and attempts to isolate the parasite from raw goat milk samples. Between October 2020 and December 2022, blood samples were collected from 460 goats, and 220 milk samples were taken from goats raised in the Rio de Janeiro state, Brazil. The serum samples were tested for anti-T. gondii IgG antibodies using IFAT. The milk samples were tested for parasitic DNA detection using nPCR, and attempts were made to isolate the protozoan in mice. For risk factor analysis, the farmers answered a semi-structured questionnaire covering various epidemiological variables. Overall, 24.1% tested positive for anti-T. gondii IgG in serum samples. Risk factors included farm location, age group, rearing system, presence of cats, grazing, and access of cats to water sources. In nPCR, 38.6% were positive, but none were positive in the bioassay. However, 3.2% of the mice inoculated with goat milk seroconverted. This study found that the exposure of dairy goats in Rio de Janeiro to T. gondii is driven by ineffective management practices in preventing and controlling the parasite in these animals. Moreover, despite the detection of parasitic DNA in raw goat milk, the shedding of viable parasites in milk from naturally exposed goats appears to be low., Competing Interests: Declarations. Competing interests: The authors declare no competing interests. Statement of animal ethics: This study was approved by the Ethics Committee for the Use of Animals of the Oswaldo Cruz Institute/Fiocruz under license number L-041/2019 and by the Ethics Committee for Research with Human Beings of the Antônio Pedro University Hospital of the Faculty of Medicine of the Fluminense Federal University under CAAE number 29260919.1.0000.5243 and opinion 3.963.040., (© 2025. The Author(s), under exclusive licence to Springer Nature B.V.)

Anti-Toxoplasma gondii antibodies were investigated in 125 Saimiri spp. kept at a research institute. A total of 12% of primates tested positive, all of which were Saimiri sciureus. These results highlight the need to minimize the possibility of this protozoan's circulation, which can lead to fulminant infection in these animals., (© 2024 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Toxoplasma gondii is a zoonotic parasite with global distribution capable of infecting homeothermic animals. Transmission of protozoan to humans includes ingestion of water and raw food contaminated with sporulated oocysts, ingestion of raw or undercooked meat with tissue cysts, and tachyzoites' transplacental transmission. Fresh goat milk intake has already been linked to human toxoplasmosis outbreaks, but little is known about the infectious potential of this biological sample. Accordingly, the aim of the present study is to assess the survival and infectivity of T. gondii tachyzoites in fresh goat milk samples through an experimental protocol to detect this parasite via bioassay carried out with a murine model, DNA amplification, and serology. Swiss Webster mice were inoculated with fresh goat milk samples contaminated with different T. gondii RH strain tachyzoite concentrations per milliliter and stored for different refrigeration times. Animals showing clinical signs compatible to toxoplasmosis were euthanized. Milk samples contaminated with high parasitic loads and kept for a shorter refrigeration time were the most lethal ones. No significant differences were observed between mean death rates recorded for different goat milk contamination concentrations ( p = 0.1888), and for the refrigeration time, contaminated milk samples were kept under ( p = 0.9440). T. gondii DNA was amplified in all contaminated milk samples, but only one of the surviving mice was serologically positive. Results of the present study have shown T. gondii survival and infectivity in fresh goat milk samples, and it highlights its significant risk for public health. Therefore, molecular methods must be the tests of choice when milk samples are used to assess infection caused by protozoan in goats' dairy products., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2024 Igor Falco Arruda et al.)

Balantioides coli is a ciliated protist that can cause dysentery in humans, pigs and nonhuman primates and may have the potential for zoonotic transmission. Its diagnosis is routinely performed through conventional parasitological techniques, and few studies have used culturing techniques to isolate it, applying molecular tools for the characterization of this protozoan. Thus, the objective of this study was to confirm B. coli diagnosis using molecular tools and to characterize the genetic variants of this parasite isolated from pigs kept on family farms in Brazil using three different culture media that differed in the serum added. Fecal samples from pigs were inoculated in Pavlova medium plus coconut water (PC), fetal bovine serum (PB) and horse serum (PH). Of the 127 samples positive for forms compatible with the phylum Ciliophora, 31 were selected for isolation. The most successful medium for isolation was PB 19/31 (61.3%), followed by PH 18/31 (58.1%) and PC 11/31 (35.5%). Of the nucleotide sequences generated, 20 were classified as genetic variant type B0, two as A1 and 15 as A0. The results indicated that PC, despite having allowed the isolation of B. coli for a short period, was not an adequate medium for the maintenance of this parasite in vitro, therefore requiring improvement.

Intestinal protozoa, which can be asymptomatic or cause diarrhea, dysentery and even death, are among the main agents that affect nonhuman primates (NHPs) kept under human care. Nevertheless, information on the molecular and morphometric profiles of parabasilids in the Neotropics is still scarce. In this context, the objective of this study was to isolate the Parabasalia protozoa detected in the feces of NHPs and their keepers in Pavlova and TYSGM9 media and to characterize the isolates by molecular biology and morphometry. Fecal samples from NHPs from five Brazilian institutions were analyzed. Direct examination was performed immediately after obtaining the samples. A total of 511 fecal samples from NHPs were collected, and 10.6% contained parabasilids. Regarding the handlers, of the 74 samples analyzed, three were positive. In vitro-generated parabasilid isolates were successfully obtained from all positive samples, as identified via microscopy. Isolates of the parasite were obtained both from New World NHPs, including the genera Leontopithecus , Saguinus , Leontocebus , Aotus , Saimiri , Sapajus , and Alouatta, and from the Old World primate Pan troglodytes . Forty-nine NHP isolates were molecularly identified: Pentatrichomonas hominis (16), Trichomitus batrachorum (14), Tetratrichomonas brumpti (13) and Hypotrichomonas hampli (6). The human isolates were identified as Tetratrichomonas sp. (2) and T. batrachorum (1). Visualization and morphometric analysis revealed trophozoites with piriform or rounded shapes that presented variable measurements. The isolates previously characterized as P. hominis had up to five free flagella, while T. batrachorum and Tetratrichomonas sp. had up to four free flagella, and H. hampli had a maximum of three free flagella. These morphometric characteristics corroborated the molecular identification. In general, a variety of parabasilids were observed to infect NHPs, and T. batrachorum was isolated from biological samples from both NHPs and their keepers, a finding that reinforces the susceptibility of these hosts to infections by parabasilids in Brazil., Competing Interests: We, Lais Verdan Dib, Alynne da Silva Barbosa, Lais Lisboa Correa, Breno da Silva Torres, Alcides Pissinatti, Silvia Bahadian Moreira, Rodrigo Hidalgo Friciello Teixeira, André Luíz Mota da Costa, José Augusto Pereira Carneiro Muniz, Amauri Michel Junglos, Zelinda Maria Braga Hirano, and Maria Regina Reis Amendoeira, authors from the manuscript intitled “Morphological and molecular characterization of parabasilids isolated from ex situ nonhuman primates and their keepers at different institutions in Brazil” report no conflict of interest., (© 2024 The Authors.)

The highly virulent Toxoplasma gondii RH strain is maintained through successive passages in mice, but there is still a lack of studies that refine these procedures from a 3Rs perspective, where humanitarian ideals aim to minimize the stress, pain, or suffering of the animals used in the research without the loss of results. The aim of this study was to establish humane endpoints in Swiss Webster mice inoculated with the T. gondii RH strain. A total of 52 mice were infected with 5 × 10 6 tachyzoites/mL and monitored for periods of up to 5 days. The parameters body weight; hair condition; higher than normal body temperature; hypothermia; respiratory function; pain; soft stools or diarrhea; bloody diarrhea; tense, nervous, or in distress during handling; and ascites were recorded daily in score tables. The results showed that prominent piloerection, respiratory function, pain parameters, and ascites are important clinical signs to be used as a cut-off point for implementing euthanasia. The application of this refinement method helped to avoid animal suffering and pain without compromising the number of parasites recovered. We therefore suggest adopting these parameters in research protocols that require the maintenance of the T. gondii RH strain in murine models to avoid and reduce animal suffering.

Ocular toxoplasmosis (OT) is caused by protozoan T. gondii. Ophthalmological examination is considered the gold standard for OT diagnosis, and laboratory tests are used for diagnostic confirmation. However, these tests can present different results, which change depending on their basis, on sample type and on patients' clinical alteration. Thus, the aim of the present study is to assess immunodiagnostic and molecular techniques applied in blood, serum and tear fluid to diagnose T. gondii infection in patients seen at an Ophthalmology Clinic. In total, 160 patients were included in the study, 40 of them had OT with active lesions (G1); 40 had OT with healed lesions (G2), 40 had non-toxoplasmic uveitis (G3) and 40 had no ocular alterations (G4). Serum samples were subjected to Immunoenzymatic Assay (ELISA) and to Indirect Immunofluorescence Reaction (IFAT) to search for anti-T. gondii IgM and IgG. Tear fluid samples were analyzed through ELISA for IgA research. All blood and tear fluid samples were subjected to conventional polymerase chain reaction (cPCR) and in a Nested PCR model for T. gondii DNA amplification with targets B1, GRA7 and REP 529. IgG and IgM anti-T. gondii was detected in serum samples from 106 and 15 patients, respectively, when combining ELISA and IFAT results. Anti-T.gondii IgA antibodies were detected in 9.2% of the tear material. Nested PCR with GRA7 target showed higher positivity in blood samples (24.4%); Nested PCR with B1 target showed a higher frequency of positivity in tears (15%). Biological samples of patients with active lesions showed the highest positivity frequencies in all immunodiagnostic assays, as well as in most PCR models. The present results highlighted the need of associating techniques with different fundamentals to confirm OT diagnosis. Furthermore, further tear fluid analyses should be performed to validate this biological material as lesser invasive alternative for the more accurate OT diagnosis., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Ramos et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Introduction: Toxoplasmosis is a worldwide distributed zoonosis caused by Toxoplasma gondii (T. gondii ), an obligate intracellular protozoan. The infection in immunocompetent hosts usually progresses with mild or no symptoms. However, in immunocompromised individuals, this disease can cause severe or fatal symptoms., Method: Sulfadiazine and pyrimethamine are two drugs used as standard therapies for human toxoplasmosis. Although they do not cause chronic infection, they may cause hematological toxicity, hypersensitivity, intolerance, teratogenic effects, gastrointestinal disorders, and bone marrow suppression., Results: The limited effect, significant toxicity, and emerging resistance to current drugs available to treat T. gondii infections require investigating other effective, nontoxic, and well-tolerated alternatives. Medicinal plants are, traditionally, the most promising sources used to treat infectious diseases Conclusion: This review provides data on new therapeutic and prophylactic methods for T. gondii infection based on the use of extracts and/or compounds derived from natural products, which have been reported to be useful as alternative treatment options in the last 20 years., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

This communication aimed to determine the frequency of infection by T. gondii and other gastrointestinal parasites in free-living cats captured in BioParque do Rio (Fundação RioZoo), Brazil. To this end, 58 blood and 51 fecal samples were collected from 68 cats from July 2019 to September 2020. The serum obtained was analyzed by indirect fluorescent antibody test for anti- T. gondii IgG. Fecal samples were examined by microscopic parasitological techniques. Of the total, 10.3% of the animals presented anti- T. gondii IgG. Parasitic structures were observed in 39.2% of the fecal samples. Hookworms were the most detected parasites (19.6%) followed by Cystoisospora sp. (11.7%), Dipylidium caninum (7.8%) and Toxocara cati (3.9%). These results indicated the exposure of this population of stray cats to potentially zoonotic parasites, which in addition to causing possible damage to domestic and wild animal health, also pose risks to public health., Competing Interests: Conflict of interests: IFA, RCFR, ASB, GVE, AMA, FT and MRRA - No conflict of interest.

Toxoplasmosis is an important zoonotic disease caused by the parasite Toxoplasma gondii and is especially fatal for neotropical primates. In Brazil, the Ministry of Health is responsible for national epizootic surveillance, but some diseases are still neglected. Here, we present an integrated investigation of an outbreak that occurred during the first year of the COVID-19 pandemic among eleven neotropical primates housed at a primatology center in Brazil. After presenting non-specific clinical signs, all animals died within four days. A wide range of pathogens were evaluated, and we successfully identified T. gondii as the causative agent within four days after necropsies. The liver was the most affected organ, presenting hemorrhage and hepatocellular necrosis. Tachyzoites and bradyzoite cysts were observed in histological examinations and immunohistochemistry in different organs; in addition, parasitic DNA was detected through PCR in blood samples from all specimens evaluated. A high prevalence of Escherichia coli was also observed, indicating sepsis. This case highlights some of the obstacles faced by the current Brazilian surveillance system. A diagnosis was obtained through the integrated action of researchers since investigation for toxoplasmosis is currently absent in national guidelines. An interdisciplinary investigation could be a possible model for future epizootic investigations in animals.

Background: The purpose of this study was to identify the species of artiodactyl host related to the fecal matter collected in a forest area in Rio de Janeiro state and carry out a parasitological investigation., Methods: Artiodactyl feces were collected between 2020 and 2021. The fecal samples were examined to identify the host through macroscopic and molecular analysis. The remaining samples were subjected to a fecal parasite analysis using microscopic techniques, and feces containing cysts of the phylum Ciliophora underwent a molecular analysis., Results: Of the 101 samples collected, 71.3% were found in Pavão Valley, the most anthropized area of the park. In the molecular analysis, 79 samples were identified as belonging to Sus scrofa and 2 as Mazama gouazoubira . The most frequently detected forms were cysts of the phylum Ciliophora (39.6%), followed by eggs of Ascaris spp. (11.8%) and Metastrongylus spp. (5.9%). Nucleotide sequences of Balantioides coli were characterized in 26 samples, and in 13 samples variants of type B0 and in 11 type A0 were identified., Conclusions: It should be noted that this is the first study in the Americas that has identified B. coli in free-living S. scrofa feces, citing this bioinvader as one of the reservoirs of this parasite.

A serologic and epidemiologic study was carried out in order to determinate herd and animal seroprevalence and associated factors for Toxoplasma gondii in commercial pigs from Espírito Santo state, Brazil. Blood samples were collected from 416 pigs from 55 producer farms in 27 municipalities. An indirect immunofluorescent assay (IFA) was performed to estimate the seroprevalence of T. gondii and identify the associated risk factors using a questionnaire. The T. gondii antibody prevalence rate in commercial swine herds was 15.4% (64/416) using a cutoff of 1:64. The seropositivity for T. gondii was related to the presence of cats, water origin and age of swine in the increase of seroprevalence, and the existence of internal isolation fences and use of composting chambers as protective factors. To the best of our knowledge, this is the first study to report anti- T. gondii antibodies in the serum of pigs in the state of Espírito Santo, Brazil. This finding is important to public health because seropositive pigs can harbor tissue cysts in their meat, thereby representing a zoonotic risk for consumers of raw or undercooked porcine meat or its products.

Hepatitis E virus (HEV) infection has been demonstrated in various animal species; those recognized as potential zoonotic reservoirs pose a considerable risk to public health. In Brazil, HEV-3 is the only genotype identified in humans and swine nationwide, in a colony-breeding cynomolgus monkey and, recently, in bovines and capybara. There is no information regarding HEV exposure in the equine population in Brazil. This study aimed to investigate anti-HEV antibodies and viral RNA in serum samples from horses slaughtered for meat export and those bred for sport/reproduction purposes. We used a commercially available ELISA kit modified to detect species-specific anti-HEV, using an anti-horse IgG-peroxidase conjugate and evaluating different cutoff formulas and assay precision. Serum samples (n = 257) were tested for anti-HEV IgG and HEV RNA by nested RT-PCR and RT-qPCR. The overall anti-HEV seroprevalence was 26.5% (68/257) without the detection of HEV RNA. Most municipalities (53.3%) and farms (58.8%) had positive horses. Animals slaughtered for human consumption had higher risk of HEV exposure (45.5%) than those bred for sports or reproduction (6.4%) ( p < 0.0001). The statistical analysis revealed sex and breeding system as possible risk-associated factors. The first serological evidence of HEV circulation in Brazilian equines reinforces the need for the surveillance of HEV host expansion in a one-health approach.

The use of medicinal plants as raw material for extracts production and pure substances isolation and subsequence development of new drugs represents a constantly growing area. However, some stages are indispensable before pharmacologically evaluating natural products such as medicines. Toxicity tests in mammalian cells are essential to initiate new drugs development or verify the substance's biocompatibility. Thus, we verified the toxicity of crude extracts and fractions with different polarities obtained from the leaves and stems of eight plant species. The toxic effect was evaluated on macrophages obtained from the bone marrow and peritoneal cavity of a Swiss webster mouse and J774 macrophages. G8 cell lineage. These macrophages were cultured in a 96-well plate, and the compounds were added at a concentration of 100 µg/mL for 24 hours. After this time, the supernatant was removed. The toxicity was evaluated for lactate dehydrogenase (LDH) release assay and the resazurin assay, which uses an indicator dye to measure oxidation-reduction reactions. The results showed a difference in the percentage of toxicity when comparing the same extract in different types of macrophages. This outcome indicates that these cells from different origins may exhibit different responses when exposed to the same natural compounds.

Background: Recurrence is a hallmark of ocular toxoplasmosis (OT), and conditions that influence its occurrence remain a challenge. Natural killer cells (NK) are effectors cells whose primary is cytotoxic function against many parasites, including Toxoplasma gondii. Among the NK cell receptors, immunoglobulin-like receptors (KIR) deserve attention due to their high polymorphism., Objectives: This study aimed to analyse the influence of KIR gene polymorphism in the course of OT infection and its association with recurrences after an active episode., Methods: Ninety-six patients from the Ophthalmologic Clinic of the National Institute of Infectology Evandro Chagas were followed for up to five years. After DNA extraction, genotyping of the patients was performed by polymerase chain reaction sequence-specific oligonucleotide (PCR-SSO) utilising Luminex equipment for reading. During follow-up, 60.4% had a recurrence., Findings: We identified 25 KIR genotypes and found a higher frequency of genotype 1 (31.7%) with worldwide distribution. We note that the KIR2DL2 inhibitor gene and the gene activator KIR2DS2 were more frequent in patients without recurrence. Additionally, we observed that individuals who carry these genes progressed recurrence episodes slowly compared to individuals who do not carry these genes., Main Conclusions: The KIR2DL2 and KIR2DS2 are associated as possible protection markers against ocular toxoplasmosis recurrence (OTR).

This purpose of this study was to compare the efficiency of the McMaster and Mini-FLOTAC quantitative techniques in the investigation of helminths in feces of pigs. An analysis was made of 74 fecal samples from pigs raised on family farms located in Rio de Janeiro, Brazil. These were analyzed by the Mini-FLOTAC and McMaster techniques in a solution of 1,200g/mL NaCl. This investigation revealed a superiority in the frequency of all helminths detected by Mini-FLOTAC, including Ascaris suum, Trichuris suis, strongyles and Strongyloides ransomi. The Kappa index revealed substantial agreement in all comparisons made in relation to the frequency of positive samples. However, significant statistical differences in the comparison of EPGs between McMaster and Mini-FLOTAC were observed for all nematodes (p ≤0.05). Higher values of Pearson's linear correlation coefficient (r), between the techniques in relation to EPG were observed for A. suum and T. suis, differently from what was observed for strongyles and S. ransomi. Mini-FLOTAC proved to be a more satisfactory and reliable technique both for the diagnosis of parasites and for the determination of EPG in pig feces due to the larger size of its counting chambers, thus increasing the helminth egg recovery rates.

A 10-year-old black howler monkey presented with a 36-day subacute clinicopathological picture of fever, prostration, inappetence, intestinal hypomotility, and emaciation. Therapy was trimethoprim-sulfamethoxazole with streptomycin. The liver, lungs, lymph nodes, and spleen presented lesions. Toxoplasma gondii isolation and PCR determined the diagnosis, and indirect fluorescent antibody tests confirmed an increase in antibody titers., (© 2022 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Urban canine and feline populations are expanding worldwide, a fact that can boost the transmission of zoonotic parasites. Thus, it is necessary understanding dog and cat owners' profile, as well as their perceptions about zoonoses, to develop preventive strategies based on the One Health approach. The aim of the current study is to compare the profile of dog and cat owners, whose domestic pets were treated at Jorge Vaitsman Veterinary Medicine Center, Rio de Janeiro, Brazil. Dog and cat owners, whose domestic pets were treated in the routine service of the aforementioned medical clinic, from August 2017 to November 2018, filled a structured questionnaire comprising closed questions in order to collect information about their socioeconomic profile, hygiene habits, animal care and knowledge about parasites. Comparative analysis was applied to data collected from dog and cat owners, based on using Fischer's Exact Test or Pearson's Chi-square. In total, 350 individuals - 244 dog owners and 106 cat owners - filled the questionnaire. The comparative analysis of socioeconomic profile, animal care, sanitary practices and knowledge about parasites did not show differences between dog and cat owners (p≥0.05). Animal vaccination and deworming practices were significantly more prevalent among dog owners than among cat owners (p≤0.05). Overall, respondents have shown lack of knowledge about parasitic zoonoses. Results in the current study have evidenced the need of mediating and promoting information about potentially zoonotic parasitic agents among domestic pet owners, as well as the key role played by veterinarians as mediators of primary prevention measures against these agents., Competing Interests: Conflicts of interests: IFA, YACM, TFB, IMSG, PRM, ASB, LCSA and MRRA – No conflict of interest., (Copyright Arruda et al.)

Background: Toxoplasma gondii is a apicomplexan parasite of virtually all warm-blooded species. All true cats (Felidae) can act as definitive hosts for this parasite by shedding resistant oocysts into the environment. However, the patterns of oocysts shedding are only partially understood in domestic cats and largely unknown in wild felids., Objectives: We carried out molecular analysis of 82 faecal samples from wild felids collected in the Serra dos Órgãos National Park (Parnaso), Rio de Janeiro, Brazil., Methods: We screened samples for T. gondii DNA using a quantitative polymerase chain reaction (qPCR) targeting the 529bp DNA fragment. Polymerase chain reaction (PCR)-positive samples were genotyped using 15 microsatellite markers., Results: Only one faecal sample from a Puma yagouaroundi was PCR-positive [cycle threshold (Ct) = 26.88]. This sample was contaminated by a T. gondii strain of BrIII lineage, a common lineage in domestic animals from Brazil., Main Conclusions: This first report of T. gondii in faeces of wild South American felids in their natural environment indicates infrequent oocyst shedding and suggests a role of acquired immunity in limiting re-excretion as in domestic cats. The presence of a domestic strain of T. gondii in a faecal sample from a wild felid at very low concentrations (not detected by microscopy) is consistent with the hypothesis of host-parasite co-adaptations limiting the circulation of T. gondii strains between domestic and wild environments.

This study reports on infection by Prosthernorchis elegans of Callithrix aurita and Leonthopithecus rosalia through biometry on adults and by molecular biology. Seventy-eight helminths were recovered from the animals' intestine. This is a detailed morphological description and the first molecular characterization of P. elegans in animals from Brazil., (© 2022 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

An analysis was made of the frequency of Cryptosporidium spp. in fecal samples from horses raised on farms in the Teresópolis city, state of Rio de Janeiro, Brazil, and the risk factors that favored this infection. Between 2019 and 2020, 314 samples of equine feces were collected, 287 of which came from English Thoroughbred horses and 27 from ponies. Information on the horses and their management were retrieved from a stud book and forms filled out by trainers. The fecal samples were subjected to macroscopic analysis, modified Sheather's and Lutz parasitological techniques, safranin staining, and to enzyme-linked immunosorbent assay (ELISA) for the detection of coproantigens. All the samples that tested positive by these techniques underwent partial sequence analysis of the 18S rRNA gene to characterize the protozoan species. Cryptosporidium spp. was identified in 35 (11.1%) of the samples, 34 from English Thoroughbred horses and one from a pony. Based on a logistic regression model, it was found that the presence of dogs and small ruminants on the farms, and drinking water from a spring, were significantly associated with the animals' infection by the protozoan (p < 0.05). Eight of the English Thoroughbred horse samples underwent molecular characterization, which revealed the presence of Cryptosporidium felis in one sample and Cryptosporidium parvum in seven. The seven samples containing C. parvum were subjected to gp60 gene analysis, based on which nucleotide sequences typical of the IIa family were identified, which are usually transmitted from animals to humans. In addition, the genotype IIaA15G2R1, which is considered to have the highest profile of zoonotic transmissibility, was identified in one Thoroughbred horse. This is the first study conducted in the state of Rio de Janeiro that molecularly characterized Cryptosporidium spp. in horses, and the first on the American continent to detect C. felis in the feces of these animals., (Copyright © 2021. Published by Elsevier B.V.)

Competing Interests: The authors declared no conflicts of interest [check statement to match COI form]

Toxoplasma gondii is a zoonotic parasite of worldwide distribution that can infect several species of homeothermic animals. Few studies have evaluated the exposure of captive wild animals to T. gondii. This study involved a serological survey of anti-T. gondii antibodies in mammals kept in Cuba's National Zoo (PZN) and in the Rio de Janeiro Zoo (RIOZOO) in Brazil. The study consisted of a total of 231 serum samples from mammals, 108 from PZN and 123 from RIOZOO. All the samples were subjected to IgG anti-T. gondii testing by means of the inhibition ELISA method and the modified agglutination test, respectively. T. gondii antibodies were detected in 85.2% samples from PZN and 32.5% samples from RIOZOO. At the PZN, Perissodactyla (92.3%) was the order with the highest serological prevalence rate, whereas at the RIOZOO, the order Primates (46.7%) stood out (p<0.05). In addition to this association, the origin of the PZN animals was also associated with T. gondii infection. This finding demonstrates the need for constant veterinary monitoring of captive wild mammals in order to link the serological diagnosis with clinical alterations indicative of toxoplasmosis.

The urban populations of pets, mainly dogs and cats, have been growing in recent years and, consequently, human-animal relationships have become increasingly closer. However, pets are vulnerable to infection by various parasites, as well are their owners due to the zoonotic potential of these agents. This study aimed to assess the frequency and risk factors of intestinal parasites in dogs and cats attended at the Municipal Institute of Veterinary Medicine Jorge Vaitsman, Rio de Janeiro, Brazil, as well as georeferencing the parasitized animals. A total of 608 animals (400 dogs and 208 cats) were enrolled from August 2017 to November 2018. Fecal samples were obtained from the animal's rectum during clinical examination. In addition, the owners of the enrolled dogs and cats were asked to complete an epidemiological questionnaire with questions about the animals' general information, lifestyle, and handling. Fecal samples were subjected to sedimentation and centrifugal-flotation in sucrose solution techniques. The frequencies of intestinal parasites total in dogs and cats were 11.3% and 24.5%, respectively, with hookworms being the most detected parasites in dogs (8.3%) and Dipylidium caninum in cats (12.5%). Sex was the only variable that showed statistical differences in the canine population males being more often infected than female (p < 0.05), while street access was associated with parasitic infections in cats (p < 0.05). The results obtained in this study demonstrate the need to control parasitic infections in domiciled dogs and cats in different municipalities in the metropolitan region of the state of Rio de Janeiro, including residents in the northern, western and central areas., (Copyright © 2021. Published by Elsevier B.V.)

In canine leishmaniosis caused by the protozoan Leishmania infantum, little is known about how co-infections with or co-seropositivities for other pathogens can influence aggravation of this disease. Therefore, the objectives of this study were to evaluate the frequency of co-infections with or co-seropositivities for certain pathogens in dogs seropositive for L. infantum and their relationship with clinical signs, histological changes and L. infantum load. Sixty-six L. infantum-seropositive dogs were submitted to clinical examination, collection of blood and bone marrow, culling, and necropsy. Antibodies against Anaplasma spp., Borrelia burgdorferi sensu lato, Ehrlichia spp. and Toxoplasma gondii and Dirofilaria immitis antigens were investigated in serum. Samples from different tissues were submitted to histopathology and immunohistochemistry for the detection of Leishmania spp. and T. gondii. Quantitative real-time PCR was used to assess the L. infantum load in spleen samples. For detection of Coxiella burnetii, conventional PCR and nested PCR were performed using bone marrow samples. All 66 dogs tested positive for L. infantum by qPCR and/or culture. Fifty dogs (76%) were co-seropositive for at least one pathogen: T. gondii (59%), Ehrlichia spp., (41%), and Anaplasma spp. (18%). Clinical signs were observed in 15 (94%) dogs monoinfected with L. infantum and in 45 (90%) dogs co-seropositive for certain pathogens. The L. infantum load in spleen and skin did not differ significantly between monoinfected and co-seropositive dogs. The number of inflammatory cells was higher in the spleen, lung and mammary gland of co-seropositive dogs and in the mitral valve of monoinfected dogs. These results suggest that dogs infected with L. infantum and co-seropositive for certain pathogens are common in the region studied. However, co-seropositivities for certain pathogens did not aggravate clinical signs or L. infantum load, although they were associated with a more intense inflammatory reaction in some organs., Competing Interests: The authors have declared that no competing interests exist.

This study aimed to genetically characterize Toxoplasma gondii isolates obtained from free-range chickens reared in the metropolitan region of the state of Rio de Janeiro, Brazil, and to evaluate the morbidity and histological changes associated with these isolates in mice. A mouse bioassay was used to isolate T. gondii from a pool of tissue samples (brain, heart, and thigh muscles) collected from 163 chickens. The 36 isolates obtained were genetically characterized by restriction fragment polymorphism (PCR-RFLP) analysis of the SAG1, 5'-3'SAG2, aSAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, Apico, and CS3 genomic regions. Seventeen atypical genotypes were identified and nine of them were reported for the first time. All identified genotypes caused clinical signs and histological changes in mice, with the majority being associated with high cumulative morbidity (65%) and severe or very severe histological changes (76%). The exclusive identification of atypical genotypes, with a predominance of new genotypes, indicates great genetic diversity of T. gondii in the region studied. In addition, the finding that all identified genotypes caused clinical signs and often severe histological changes in mice suggests potentially relevant virulence of these strains.

Toxoplasma gondii is a highly prevalent zoonotic parasite in Brazil capable of infecting mammals and birds. The increase in the urban populations of pets and the narrowing of the human-animal relationship can facilitate the transmission of important public health zoonoses, such as toxoplasmosis. This study aimed to evaluate the frequency and spatial distribution of T. gondii infection and its risk factors in domiciled dogs and cats attended at the Jorge Vaitsman Institute, Rio de Janeiro. Serum samples from 400 dogs and 272 cats were evaluated by an indirect fluorescent antibody test (IFAT) for IgG anti-T. gondii antibodies. Epidemiological questionnaires were used to interview the animals' owners to identify risk factors for infection. Of the total, 34% (136/400) of dogs and 8.1% (22/272) of cats had anti-T. gondii antibodies. Breed (OR: 2.10-95%, CI 1.27-3.46) was a risk factor for dogs, while sex (OR: 3.40-95%, CI 1.10-10.52) and homemade food consumption (OR: 8.49-95%, CI 2.48-29.05) were risk factors for cats. Offal consumption was considered a risk factor for both species evaluated (OR: 2.74-95%, CI 1.38-5.43 for dogs; OR: 7.66-95%, CI 1.24-47.29 for cats). The spatial analysis showed that T. gondii seropositive animals were widely distributed in the metropolitan region of Rio de Janeiro state, with a concentration observed mainly in the west and north zones of Rio de Janeiro city. The results emphasize the importance of adopting prophylactic measures to control T. gondii transmission in domiciled dogs and cats in Rio de Janeiro, contributing positively to public health., (© I.F. Arruda et al., published by EDP Sciences, 2021.)

Toxoplasmosis is a worldwide zoonosis caused by Toxoplasma gondii. Ingestion of raw/undercooked meat is considering an important route of infection. Consumption of meat from equids is common in European and Asian countries and an increase in Brazil has been observed. The aim of this study was to evaluate occurrences of anti-T. gondii antibodies and risk factors relating to infection in equids slaughtered for human consumption in Minas Gerais, Brazil. Blood samples from 192 horses and 208 donkeys were collected in the exsanguination area during the slaughter. Serum samples were subjected to the indirect fluorescent antibody test (IFAT). Association analysis was performed using Pearson's chi-square test (χ2) or Fisher's exact test, to evaluate risk factors relating to the prevalence of seroreagents. Antibodies against T. gondii were found in 13.5% of the equids, with higher occurrence in horses (18.75%) than in donkeys (8.65%). Associations between seropositivity and the following variables were found (p ≤ 0.05): species, animal origin, purpose of rearing and source of water for animal consumption and contact with cats. Farms need to implement preventive measures to control T. gondii infection in these species and avert transmission of the parasite to the human population that will consume their meat.

Background: Non-invasive sampling through faecal collection is one of the most cost-effective alternatives for monitoring of free-living wild mammals, as it provides information on animal taxonomy as well as the dynamics of the gastrointestinal parasites that potentially infect these animals. In this context, this study aimed to perform an epidemiological survey of gastrointestinal parasites using non-invasive faecal samples from carnivores and artiodactyls identified by stool macroscopy, guard hair morphology and DNA sequencing in Itatiaia National Park. Between 2017 and 2018, faeces from carnivores and artiodactyls were collected along trails in the park. The host species were identified through macroscopic and trichological examinations and molecular biology. To investigate the parasites, the Faust, Lutz and modified Ritchie and Sheather techniques and enzyme immunoassays to detect Cryptosporidium sp. antigens were used., Results: A total of 244 stool samples were collected. The species identified were Chrysocyon brachyurus, Leopardus guttulus, Canis familiaris, Cerdocyon thous, Puma yagouaroundi, Leopardus pardalis, Puma concolor and Sus scrofa. There were 81.1% samples that were positive for parasites distributed mainly in the high part of the park. Helminths, especially eggs of the family Ascarididae, were more frequently detected in carnivore faeces (70.9%). Protozoa, especially Cryptosporidium sp., represented the highest frequency of infection in artiodactyl faeces (87.1%). This zoonotic protozoon was detected in eight mammalian species, including in a wild boar. High values of structural richness and Shannon and Simpson diversity indices were observed for the parasites, especially in the faeces of C. brachyurus. Significant differences in parasite diversity were observed between wild and domestic animals, such as C. brachyurus and C. familiaris, respectively, and between taxonomically distant species, such as C. brachyurus and S. scrofa. The highest values for parasite similarity were found among the species that frequented similar areas of the park, such as C. brachyurus and L. guttulus., Conclusions: The animals and parasite infections were identified through the combination of three techniques. High frequency parasite structures were diagnosed. Zoonotic protozoa were found and mainly occurred in samples from introduced species.

Background: Gastrointestinal parasites may determine diarrhea, dysentery or even death in captive mammals. These animals tend to be more susceptible to parasitic infections due to confinement and stress. Purpose To increase the information about these etiological agents in captive animals in Brazil, the gastrointestinal parasites of the captive mammals of the Rio de Janeiro Zoo were investigated., Methods: From 2016 to 2018, 180 fecal samples were collected from animals housed in the Rio de Janeiro Zoo: 63 from animals of the order Primates, 26 of Carnivora, 78 of Artiodactyla, 9 of Perissodactyla and 4 of the order Rheiformes. The feces were processed by direct examination and by the techniques of Faust et al., Sheather, Ritchie, Lutz, and smears were stained with safranin. Immunoenzymatic assays were also performed to investigate antigens of Giardia duodenalis, Cryptosporidium spp., Entamoeba histolytica/Entamoeba dispar., Results: Parasite positivity was identified in 68.3% of the fecal samples, with a parasite positivity rate of 68.2% among primates, 65.3% among carnivores, 69.2% among artiodactyls, 33.3% among perissodactyls, and 100% among rheiformes. The most frequently detected parasite was Entamoeba histolytica/E. dispar antigens, which showed a statistically significant positivity rate (33.3%; p = 0.000), particularly in the feces of carnivores (30.7%) and artiodactyls (53.8%). A statistically significant positivity rate of Balantioides coli (11.1%; p = 0.001) was also detected in feces from nonhuman primates, tapirs, collared peccaries and rheas. The positivity of Cryptosporidium sp. antigens in feces of the orders Carnivora, Artiodactyla and Primates was also statistically significant (7.2%, p = 0.010). Oocysts compatible with Cryptosporidium spp. were detected in 6.3% from primates. The helminths most frequently detected were thin-shelled eggs of nematodes (17.7%, p = 0.000), nematode larvae (15.5%, p = 0.000) and Trichuris trichiura eggs (6.1%, p = 0.018)., Conclusion: The positivity rate for gastrointestinal parasites demonstrates the need for a sanitation management program to be implemented in the zoo, including routine diagnostic parasitology tests followed by specific treatment for each parasitosis.

Purpose: This study aimed to compare the performance of four different microscopic coproparasitological techniques in relation to egg recovering and the frequency of alterations in the eggs observed through each technique., Methods: A total of 213 fecal samples from free-living carnivorous mammals were collected between 2017 and 2018 in Itatiaia National Park, RJ, Brazil. Faust and modified Sheather floatation techniques as well as Lutz and modified Ritchie sedimentation techniques were applied., Results: The total positivity rate for Spirometra spp. eggs was 24.4%, and these were detected mainly through Lutz and modified Ritchie sedimentation techniques, with substantial agreement (kappa = 0.73; p = 0.00 < 0.05; McNemar p value = 1.0; Fisher's exact test p = 0.616). Faust and modified Sheather flotation techniques did not present good egg recovery, with frequencies of 6.6% and 7.5%, respectively. Eggs with morphological alterations were mostly observed through Faust (17.3%) and modified Sheather (13.5%). Both flotation techniques presented statistically significant frequencies of deformed eggs, in comparison with the sedimentation techniques (p = 0.00). Low frequencies of deformed eggs were observed when the samples were analyzed through modified Ritchie and Lutz sedimentation techniques., Conclusions: From these results, sedimentation techniques such as modified Ritchie and Lutz methods were more efficient for diagnosing the eggs of this helminth in fecal material from free-living carnivores and should always be used when analyzing fecal samples from hosts of different species.

Toxoplasma gondii is the etiological agent of toxoplasmosis, a widespread zoonosis that affects several homeothermic animals, including humans. This disease causes serious health problems, such that 10% of infected individuals develop clinical manifestations. Some studies on indigenous human populations have indicated variations in seroprevalence from 10.6% to 80.4% in such populations in different regions of Brazil and in other countries like Venezuela and Malaysia. To date, there have been no studies regarding the prevalence of anti- T. gondii antibodies in Haliti-Paresí Indians living in Campo Novo do Parecis, Mato Grosso, Brazil. Our objective here was to determine the frequency of occurrence of antibodies against this protozoon in nine Haliti-Paresí villages by correlating seroprevalence with locations and variables. Serodiagnoses were made using the indirect immunofluorescence antibody test (IFAT) and enzyme-linked immunosorbent assay (ELISA) in the Laboratory for Toxoplasmosis and Other Protozoan Diseases of IOC/Fiocruz. It was considered that samples tested positive for T. gondii infection if IgG/IgM antibodies against this protozoon were detected through serodiagnosis using either IFAT or ELISA. Among the 293 samples analyzed, 66.9% presented anti- T. gondii IgG and 3.4% presented anti- T. gondii IgM. It was observed that there were no statistically significant differences in frequency of antibody occurrence among infected individuals, based on sex, schooling or occupation/activities. However, there were statistical differences based on age and villages. The prevalence observed in this study is in agreement with values found in other studies on indigenous populations in Latin America. Like among other such populations, the Haliti-Paresí villages are located close to forests and the individuals have domestic cats as pets, are involved in hunting and farming and consume water directly from water accumulation sources. These factors might cause exposure to T. gondii tissue cysts and oocysts.

The aim of this study was to identify possible infection of Toxoplasma gondii among cats in a shelter and a set of condominiums in the city of Rio de Janeiro, through changes to the cats' serological status between two different times in 2014 and 2015. One group was made up of captive cats at the municipal shelter and the other comprised stray cats that circulated in condominiums in the city. On the first occasion, cats were caught and tagged through application of microchips; in this manner, blood samples were obtained from 261 captive cats and 172 stray cats. On the second occasion, blood samples were obtained from 94 captive cats and 56 recaptured stray cats. The serological diagnosis was made by means of the indirect hemagglutination assay (IHA) and indirect immunofluorescence reaction (IFAT) (cutoff ≥ 64). The frequency of T. gondii infection among the captive cats was 24.5% and among the stray cats, 18%. With the second analysis, it was possible to verify modifications to the serological status of anti-T. gondii antibodies, in 18% of both populations of animals. The presence of seroconversion shows that infection was possibly occurring in the region at the time of the study.

Balantioides coli is a ciliated protozoon that inhabits the intestine of pigs, non-human primates and humans. Light microscopy studies have described over 50 species of the genus Balantioides but their validity is in doubt. Due to the limited information about this genus, this study is aimed to identify morphological characteristics of Balantioides coli isolated using fluorescence microscopy and both scanning (SEM) and transmission electron microscopy (TEM). Trophozoites isolated from the feces of pig and macaque were washed and subjected to centrifugation. These cells were fixed with paraformaldehyde for immunofluorescence. Other aliquots of these trophozoites were fixed with glutaraldehyde, post fixed with osmium tetroxide and processed for SEM and TEM. Immunofluorescence studies revealed microtubules with a longitudinal distribution to the main axis of the parasite and in the constitution of cilia. SEM demonstrated a high concentration of cilia covering the oral apparatus and a poor presence of such structures in cytopyge. TEM revealed in the plasma membrane, several associated structures were observed to delineate the cellular cortex and mucocysts. The cytoskeleton of the oral region was observed in detail and had an organization pattern consisting of microtubules, which formed files and nematodesmal networks. Organelles such as hydrogenosomes like and peroxisomes were observed close to the cortex. Macronuclei were observed, but structures that were consistent with micronuclei were not identified. Ultrastructural morphological analysis of isolates confirms its similarity to Balantioides coli. In this study were identified structures that had not yet been described, such as hydrogenosomes like and cytoskeletal structures.

This study aimed to investigate the species of felids that inhabit the Serra dos Órgãos National Park (Parnaso) and gastrointestinal parasites at various stages of their life cycles in the feces of these animals. Between 2013 and 2015, felid feces were collected from trails in Parnaso. The sampling points were georeferenced. A total of 82 fecal samples were processed, of which 79 were collected on the ground, two from captured felids and one from a necropsied animal. All samples underwent coproparasitological techniques. Samples collected from the environment underwent additional trichological analysis. Fur patterns corresponding to Leopardus guttulus, Leopardus pardalis, Leopardus wiedii and Puma yagouaroundi were observed in 32 of the samples collected on the soil. High frequency of potentially parasitic evolving forms (88.6%) was observed in felid feces, particularly eggs of the family Diphyllobothriidae (68.6%). Besides, were also detected, eggs of superfamily Ascaridoidea (42.9%), nematode larvae (28.6%), eggs of order Strongylida (28.6%), Capillaria sp. (8.6%), Trichuris sp. (8.6%), eggs of order Spirurida (2.9%), unsporulated coccidian oocysts (8.6%) and Eimeria sp. (2.9%). Felid feces presented higher frequency of polyparasitism (60%) than monoparasitism (28.6%).

The aim of the present study was to evaluate the growth rate of Balantidium coli in three xenic media cultures. Between 2013 and 2015, 10 B. coli isolates obtained from feces of Cynomolgus macaques, and 30 isolates from feces of pigs were studied. An inoculum of 500 trophozoites was transferred to tubes containing LES, TYSGM-9 and Pavlova media. These cultures were evaluated at incubation times of 24, 48, 72 and 96 hours. In most of strains analyzed wasn't showed significant difference in the growth rate comparing TYSGM-9 and Pavlova media (Wilcoxon p>0.016). In Pavlova medium, the trophozoites showed a maximum growth at 72 hours with significant difference when compared with the times of 24 h and 96 h (Wilcoxon <0.008). In LES, viable trophozoites were observed until 24 hours, with a significant difference (Friedman p<0.05, Wilcoxon p<0.016) in the number of parasite cells compared with Pavlova and TYSGM-9 media cultures. Thus, LES medium seemed to be less adequate than the other media for maintenance of B. coli. Despite the satisfactory results in TYSGM-9, Pavlova medium was considered ideal for the maintenance of this protozoan strain, guaranteeing the viability of the parasite with subculture every three days, presenting lower costs.

Ciliate protozoa of the genus Balantioides can parasitize a variety of animals. The morphology of the evolutionary forms of the parasite and the host species affected have long been the only characteristics used to taxonomically identify the species of these protozoa, but these variables are not very precise. To confirm species identity, molecular biology tools are currently used. In this context, this study aimed to analyze protozoan isolates maintained in culture medium and from fecal samples from captive animals in Rio de Janeiro, Brazil, by means of molecular tools. Forty isolates maintained in Pavlova modified medium (30 were isolated from feces of pigs and 10 from feces of cynomolgus macaques) were analyzed. In addition, 34 fecal samples (8 from pigs, 8 from cynomolgus macaques and 18 from rhesus macaques) containing Balantioides coli-like cysts were analyzed. All samples were subjected to DNA extraction and the polymerase chain reaction (PCR) to amplify the fragment ITS1 - 5.8s rRNA - ITS2, and the PCR products were purified and sequenced. All samples (100%) presented sequences that were grouped in the Balantioides coli cluster. The type A0 variant predominated. These sequences were 96% to 99% identical to those deposited in GenBank, including a B. coli sequence that had been obtained from human fecal material in Bolivia. It seems that the culturing system did not select variants, because this variant was also seen in the amplified sequences of fecal samples containing cysts. The isolate sequences in the cultures showed few ambiguities and substitutions, thus generating reliable chromatograms. This was the first study to identify B. coli in captive animals in Brazil, through molecular biology. In addition, it was the first to evaluate a large panel of isolates of the parasite through culturing., (Copyright © 2017 Elsevier B.V. All rights reserved.)

The increasingly urban nature of the population has led many people to choose independent pets, such as cats. This situation has also made it possible for these animals to be abandoned, thus increasing the numbers of cats on the streets and in shelters. These animals can act as a source of infection for other hosts. Between 2014 and 2015, the frequency of gastrointestinal parasites in captive and stray cats in the municipality of Rio de Janeiro was analyzed. Ninety-one fecal samples were collected from captive cats and 172 from stray cats. Centrifugal sedimentation and flotation techniques were used. The frequency of parasites among the stray cats was 77.3%, and this was significantly higher than the frequency observed in captive cats (49.5%). Helminths were detected more frequently, and hookworms were the parasites most detected. Toxocara cati, Cystoisospora sp. and Dipylidium caninum were also detected. No statistical difference in the frequency of parasites was observed between the sexes among the captive cats. However, among the stray cats, males (85.5%) presented higher positivity than females (71.8%). The high frequency of hookworms, which are the agent for "cutaneous larva migrans" in humans, shows the need to control parasitic infections among the cats studied.

Zoonotic visceral leishmaniasis is caused by the protozoan Leishmania infantum and little is known about the occurrence and pathogenesis of this parasite in the CNS. The aims of this study were to evaluate the occurrence, viability and load of L. infantum in the CNS, and to identify the neurological histological alterations associated with this protozoan and its co-infections in naturally infected dogs. Forty-eight Leishmania-seropositive dogs from which L. infantum was isolated after necropsy were examined. Cerebrospinal fluid (CSF) samples were analyzed by parasitological culture, quantitative real-time PCR (qPCR) and the rapid immunochromatographic Dual Path Platform test. Brain, spinal cord and spleen samples were submitted to parasitological culture, qPCR, and histological techniques. Additionally, anti-Toxoplasma gondii and anti-Ehrlichia canis antibodies in serum and distemper virus antigens in CSF were investigated. None of the dogs showed neurological signs. All dogs tested positive for L. infantum in the CNS. Viable forms of L. infantum were isolated from CSF, brain and spinal cord in 25% of the dogs. Anti-L. infantum antibodies were detected in CSF in 61% of 36 dogs. Inflammatory histological alterations were observed in the CNS of 31% of the animals; of these, 66% were seropositive for E. canis and/or T. gondii. Amastigote forms were associated with granulomatous non-suppurative encephalomyelitis in a dog without evidence of co-infections. The highest frequency of L. infantum DNA was observed in the brain (98%), followed by the spinal cord (96%), spleen (95%), and CSF (50%). The highest L. infantum load in CNS was found in the spinal cord. These results demonstrate that L. infantum can cross the blood-brain barrier, spread through CSF, and cause active infection in the entire CNS of dogs. Additionally, L. infantum can cause inflammation in the CNS that can lead to neurological signs with progression of the disease.