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1.
Int J Parasitol Parasites Wildl ; 22: 14-19, 2023 Dec.
Article de Anglais | MEDLINE | ID: mdl-37584011

RÉSUMÉ

Coatis (Nasua nasua) are wild carnivorous well adapted to anthropized environments especially important because they act as reservoirs hosts for many arthropod-borne zoonotic pathogens. Information about filarioids from coatis and associated Wolbachia spp. in Brazil is scant. To investigate the diversity of filarial nematodes, blood samples (n = 100 animals) were obtained from two urban areas in midwestern Brazil and analyzed using blood smears and buffy coats and cPCR assays based on the cox1, 12S rRNA, 18S rRNA, hsp70 and myoHC genes for nematodes and 16S rRNA for Wolbachia. When analyzing coati blood smears and buffy coats, 30% and 80% of the samples presented at least one microfilaria, respectively. Twenty-five cox1 sequences were obtained showing 89% nucleotide identity with Mansonella ozzardi. Phylogenetic analyses clustered cox1 sequences herein obtained within the Mansonella spp. clade. Sequences of both myoHC and two hsp70 genes showed 99.8% nucleotide identity with Mansonella sp. and clustered into a clade within Mansonella sp., previously detected in coatis from Brazil. Two blood samples were positive for Wolbachia, with a 99% nucleotide identity with Wolbachia previously found in Mansonella perstans, Mansonella ozzardi and Mansonella atelensis and in ectoparasites of the genus Pseudolynchia, Melophagus and Cimex. The study showed a high prevalence of Mansonella sp. in the coati population examined, suggesting that this animal species play a role as reservoirs of a novel, yet to be described, species within the Onchocercidae family.

2.
Parasitol Res ; 122(5): 1151-1158, 2023 May.
Article de Anglais | MEDLINE | ID: mdl-36890298

RÉSUMÉ

Procyonids are reservoirs of many zoonotic infectious diseases, including tick-borne pathogens. The role of coatis (Nasua nasua) in the epidemiology of piroplasmids and Rickettsia has not been fully addressed in Brazil. To molecularly study these agents in coatis and associated ticks, animals were sampled in two urban areas in Midwestern Brazil. Blood (n = 163) and tick (n = 248) DNA samples were screened by PCR assays targeting the 18S rRNA and gltA genes of piroplasmids and Rickettsia spp., respectively. Positive samples were further molecularly tested targeting cox-1, cox-3, ß-tubulin, cytB, and hsp70 (piroplasmid) and ompA, ompB, and htrA 17-kDa (Rickettsia spp.) genes, sequenced and phylogenetically analyzed. All coatis' blood samples were negative for piroplasmids, whereas five pools of ticks (2%) were positive for two different sequences of Babesia spp.. The first from Amblyomma sculptum nymphs was close (i.e., ≥ 99% nucleotide identity) to a Babesia sp. previously found in capybaras (Hydrochoerus hydrochaeris); the second from Amblyomma dubitatum nymphs and Amblyomma spp. larvae was identical (100% nucleotide identity) to a Babesia sp. detected in opossums (Didelphis albiventris) and associated ticks. Four samples (0.8%) were positive by PCR to two different Rickettsia spp. sequences, being the first from Amblyomma sp. larva identical to Rickettsia belli and the second from A. dubitatum nymph identical to Rickettsia species from Spotted Fever Group (SFG). The detection of piroplasmids and SFG Rickettsia sp. highlights the importance of Amblyomma spp. in the maintenance of tick-borne agents in urban parks where humans and wild and domestic animals are living in sympatry.


Sujet(s)
Babesia , Ixodidae , Procyonidae , Rickettsia , Tiques , Humains , Animaux , Rickettsia/génétique , Babesia/génétique , Brésil/épidémiologie , Rodentia , Opossum , Amblyomma , Ixodidae/microbiologie
3.
Ticks Tick Borne Dis ; 13(5): 101982, 2022 09.
Article de Anglais | MEDLINE | ID: mdl-35716428

RÉSUMÉ

This study aimed to morphologically and molecularly detect Hepatozoon procyonis in ring-tailed coatis' (Nasua nasua) blood and associated ticks from central-western Brazil, Campo Grande, Mato Grosso do Sul state and also evaluate the impact of the protozoa in blood parameters and coati´s health. Samplings were performed in a conservation area Parque Estadual do Prosa (PEP) and in a Brazilian Air Force Private Area namely Vila da Base Aérea (VBA), between March 2018 and April 2019. We collected 165 blood samples, 61 from recaptured coatis. Peripheral blood smears were stained with Romanovsky-type stain for H. procyonis parasitemia assessment. DNA extracted from blood samples and ticks (Amblyomma spp.) were submitted to a nested PCR (nPCR) assay based on the 18S rRNA gene for Hepatozoon spp. Out of 104 individuals sampled, 80 (77%) were positive for H. procyonis in at least one capture. Overall, 67/165 (40.6%) blood smears showed H. procyonis gametocytes (PEP: 41/63 - 65%; VBA: 26/102 - 25.5%). Parasitemia based on 500 assessed leucocytes ranged from 1 (0.2%) to 50 (10%) and 1 (0.2%) to 25 (5%), from animals sampled in PEP and VBA, respectively. Fluctuation on the parasitemia was observed during recaptures. nPCR results showed higher positivity when compared to blood smears, i.e. 112/165 (68%) positive blood samples [PEP: 41/63 (65%), VBA: 26/102 (25.5%)]. In total, 63/248 (25.4%) tick DNA samples were positive at nPCR for Hepatozoon sp., including 32/87 (37%) pools (1 to 10 larvae) of Amblyomma larvae, 21/105 (20%) pools (1 to 5 nymphs) of Amblyomma sculptum nymphs, 9/43 (21%) pools (1 to 5 nymphs) of Amblyomma dubitatumnymphs, and 1/12 (8%) A. sculptum adult female. The partial 18S rRNA sequence from one coati's blood sample and one representative of each positive tick species randomly selected from each area for sequencing (1,000 bp) showed 100% identity with sequences of H. procyonis from GenBank previously detected in coatis. Regarding H. procyonis infection, no statistical differences were obtained when comparing males vs. females (p-value 0.67), immature animals vs. adults (p-value 0.31), rainy vs. dry season (p-value 0.51) and sampling location (p-value 0.42). No noticeable alteration in blood parameters or heath status was observed in parasite animals. H. procyonis circulates in a high prevalence in coatis from central-western Brazil. Parasitemia fluctuates among different coatis' recaptures and apparently the infection has no influence in coatis' hematological and clinical parameters.


Sujet(s)
Apicomplexa , Carnivora , Eucoccidiida , Procyonidae , Tiques , Animaux , Apicomplexa/génétique , Brésil/épidémiologie , Eucoccidiida/génétique , Femelle , Mâle , Parasitémie/épidémiologie , Parasitémie/médecine vétérinaire , Procyonidae/parasitologie , Tiques/parasitologie
4.
J Appl Microbiol ; 131(2): 719-727, 2021 Aug.
Article de Anglais | MEDLINE | ID: mdl-33434397

RÉSUMÉ

AIM: Chemically disparate toxic organic and/or inorganic molecules produced by anthropogenic activities often hinder the bioremediation process. This research was conducted to understand the capacity of Streptomyces sp. MC1 to remove chemically disparate toxics such as Cr(VI) or phenanthrene. METHODS AND RESULTS: Genomic, metabolic modeling and proteomic approaches were used in this study. Our results demonstrated that Streptomyces sp. MC1 has the genetic determinants to remove Cr(VI) or degrade phenanthrene. Proteomics showed that these genetic determinants were expressed. Metabolic versatility of the strain was confirmed by two metabolic models in complex and minimal media. Interestingly, our results also suggested a connection between the degradation of phenanthrene and synthesis of specialized metabolites. CONCLUSIONS: Streptomyces sp. MC1 has the genetic and physiological potential to remove Cr(VI) or degrade phenanthrene SIGNIFICANCE AND IMPACT OF STUDY: The probability of a microorganism to survive in the presence of different contaminants depends on its genetic potential and the ability to express it. The genetic and proteomic profiles obtained for Streptomyces sp. MC1 can be recommended as model and predict if other Streptomyces strains can be used in bioremediation processes. Our work also hypothesized that intermediates of the phenanthrene degradation serve as precursors for the specialized metabolism.


Sujet(s)
Chrome/métabolisme , Phénanthrènes/métabolisme , Streptomyces/génétique , Streptomyces/métabolisme , Dépollution biologique de l'environnement , Génomique , Protéomique
5.
Epidemiol Infect ; 145(16): 3424-3437, 2017 12.
Article de Anglais | MEDLINE | ID: mdl-29103397

RÉSUMÉ

Anaplasmataceae agents comprise obligate intracellular bacteria that can cause disease in humans and animals. Between August 2013 and March 2015, 31 Nasua nasua (coati), 78 Cerdocyon thous (crab-eating fox), seven Leopardus pardalis (ocelot), 110 wild rodents, 30 marsupials, and 42 dogs were sampled in the Pantanal wetland, Brazil. In addition, ectoparasites found parasitizing the animals were collected and identified. The present work aimed to investigate the occurrence of Anaplasmataceae agents in wild mammals, domestic dogs and ectoparasites, by molecular and serological techniques. Overall, 14 (17·9%) C. thous, seven (16·6%) dogs and one (3·2%) N. nasua were seroreactive to Ehrlichia canis. Nine dogs, two C. thous, one N. nasua, eight wild rodents, five marsupials, eight Amblyomma sculptum, four Amblyomma parvum, 13 A. sculptum nymphal pools, two Amblyomma larvae pools and one Polygenis (Polygenis) bohlsi bohlsi flea pool were positive for Ehrlichia spp. closely related to E. canis. Seven N. nasua, two dogs, one C. thous, one L. pardalis, four wild rodents, three marsupials, 15 A. sculptum, two Amblyomma ovale, two A. parvum and one Amblyomma spp. larval pools were positive for Anaplasma spp. closely related to A. phagocytophilum or A. bovis. The present study provided evidence that wild animals from Brazilian Pantanal are exposed to Anaplasmataceae agents.


Sujet(s)
Infections à Anaplasmataceae , Anaplasmataceae , Animaux sauvages/microbiologie , Siphonaptera/microbiologie , Tiques/microbiologie , Anaplasmataceae/classification , Anaplasmataceae/génétique , Anaplasmataceae/immunologie , Anaplasmataceae/isolement et purification , Infections à Anaplasmataceae/épidémiologie , Infections à Anaplasmataceae/microbiologie , Infections à Anaplasmataceae/médecine vétérinaire , Animaux , Animaux sauvages/immunologie , Anticorps antibactériens/sang , Brésil/épidémiologie , Chiens/immunologie , Chiens/microbiologie , Renards/microbiologie
6.
Transbound Emerg Dis ; 64(6): e36-e42, 2017 Dec.
Article de Anglais | MEDLINE | ID: mdl-28233434

RÉSUMÉ

The multihost parasites Leishmania spp. infect a broad range of wild mammalian species including bats. Several species of bats have adapted to a variety of food resources and shelters in urban areas. This study aimed to detect Leishmania spp. DNA in bats present in forest fragments located in metropolitan areas endemic for leishmaniasis in Campo Grande, Mato Grosso do Sul (MS), Brazil. Blood samples were obtained from 80 individuals, including eight species of Phyllostomidae and one species of Vespertilionidae. Thirty of the 80 bats were positive for Leishmania spp. using conventional PCR, all belonging to the family Phyllostomidae. Eighteen samples tested by real-time PCR (qPCR) using specific primers for the kDNA of Leishmania infantum were positive. To the best of our knowledge, this is the first report detecting Leishmania spp. in Platyrrhinus incarum in addition to being the first reported detection of L. infantum in the bat species Phyllostomus discolor, Platyrrhinus lineatus, Artibeus planirostris and Artibeus lituratus. Our results show that bats can host Leishmania spp. in areas endemic for leishmaniasis, which must be taken into account in disease control operations by public health authorities.


Sujet(s)
Chiroptera , Leishmania/isolement et purification , Leishmaniose/médecine vétérinaire , Animaux , Brésil/épidémiologie , Leishmania/classification , Leishmaniose/épidémiologie , Leishmaniose/parasitologie , Réaction de polymérisation en chaine en temps réel
7.
Vet Microbiol ; 165(3-4): 448-54, 2013 Aug 30.
Article de Anglais | MEDLINE | ID: mdl-23639473

RÉSUMÉ

The feral swine (FS) originated from the domestic pig and is present throughout the Brazilian wetland plain (the Pantanal). Aujeszky's disease (AD) was first serologically confirmed in the state of Mato Grosso do Sul (MS) in 2001; however, there was no viral confirmation. The aim of this study was to investigate antibodies against-SuHV-1 in the sera of feral swine in the studied areas, detect SuHV-1 through PCR and classify the viral genome. Among the 218 animals sampled, 186 were analyzed by ELISA, resulting in 88 (47.3%) reactive samples. In the serum neutralization test (SN), 57/179 (31.8%) samples presented antibodies against the AD virus (SuHV-1). By nested PCR, 104 DNA samples were extracted for analysis and confirmed with amplification of a fragment of glycoprotein B (gB) in five samples. The SuHV-1 was detected in 12 samples by using primers for glycoprotein E (gE) and viral genome was classified as Type I by ul44 partial sequencing. The amplification of SuHV-1 glycoprotein fragments in the fetuses of seropositive sows indicate that the vertical transmission contribute to maintain SuHV-1 in a free-living feral swine population. The origin of AD in the feral swine populations of the Pantanal is unknown, however, the determination of viral latency, the vertical transmission of the antigen by the amplification of SuHV-1 glycoprotein fragments in the fetuses of seropositive sows and genome typing contribute to the elucidation of the epidemiology of this disease in the wetlands of MS, Brazil.


Sujet(s)
Herpèsvirus porcin de type 1/physiologie , Maladie d'Aujeszky/épidémiologie , Maladies des porcs/épidémiologie , Zones humides , Animaux , Brésil/épidémiologie , Test ELISA/médecine vétérinaire , Femelle , Foetus/virologie , Génome viral/génétique , Herpèsvirus porcin de type 1/génétique , Herpèsvirus porcin de type 1/immunologie , Transmission verticale de maladie infectieuse , Grossesse , Prévalence , Maladie d'Aujeszky/transmission , Maladie d'Aujeszky/virologie , Suidae , Maladies des porcs/transmission , Maladies des porcs/virologie , Protéines de l'enveloppe virale/génétique
8.
ISRN Parasitol ; 2013: 610262, 2013.
Article de Anglais | MEDLINE | ID: mdl-27335855

RÉSUMÉ

Feral pigs (S. scrofa) were introduced to the Pantanal region around 200 years ago and the population appears to be in expansion. Its eradication is considered to be impossible. The population of feral pigs in the Pantanal wetlands is currently estimated at one million. Two scientific excursions were organized. The first was conducted during the dry season, when 21 feral pigs were captured and the second was during the wet season, when 23 feral pigs were captured. Ticks were collected and the oviposition and hatching process were studied to confirm the biological success of each tick species. Three tick species were found to be feeding on feral pigs: Amblyomma cajennense, A. parvum, and Ornithodoros rostratus. During the dry season, 178 adult A. cajennense were collected, contrasting with 127 A. cajennense specimens in the wet season. This suggests that the seasonality of these ticks in the Brazilian Pantanal wetlands could be different from other regions. The results indicate that A. parvum and A. cajennense are biologically successful parasites in relation to feral pigs. A. cajennense appears to have adapted to this tick-host relationship, as well as the areas where feral pigs are abundant, and could play a role in the amplification of this tick population.

9.
Trans R Soc Trop Med Hyg ; 105(7): 380-7, 2011 Jul.
Article de Anglais | MEDLINE | ID: mdl-21600622

RÉSUMÉ

We examined by parasitological tests (hemocultures and buffy coat) infection by Trypanosoma cruzi and T. evansi in blood samples from Leopardus pardalis, Cerdocyon thous and domestic dogs. Besides, 25 T. cruzi isolates previously derived from feral pigs and small wild mammals were here characterized by miniexon gene and demonstrated to be in the TcI genotype. Herein, we make an overall analysis of the transmission cycle of both trypanosome species in the light of the assemblage of data collected over the last seven years. The carnivore Nasua nasua was confirmed to play a major role in the transmission cycles of both T. cruzi and T. evansi since it was the species that had the higher prevalence and higher parasitemias by both flagellate species. In addition, our results show that both trypanosomatid species may be found throughout the Pantanal landscape, in all forest strata, as shown by the infection of carnivore, arboreal and terrestrial scansorial marsupial species in complex and seasonal transmission cycles. We propose that transmission of T. cruzi and T. evansi in the southern Pantanal region takes place via an intricate ecological trophic network involving generalist and specialist mammal species that are linked through a robust food-web connection.


Sujet(s)
Chaine alimentaire , Trypanosomiase/médecine vétérinaire , Animaux , Animaux sauvages/parasitologie , Anticorps antiprotozoaires/analyse , Buffy coat , Brésil/épidémiologie , Maladie de Chagas/transmission , Maladie de Chagas/médecine vétérinaire , Réservoirs de maladies , Chiens/parasitologie , Felidae/parasitologie , Technique d'immunofluorescence directe/médecine vétérinaire , Renards/parasitologie , Trypanosoma , Trypanosoma cruzi , Trypanosomiase/transmission
10.
Arq. bras. med. vet. zootec ; 61(5): 1222-1226, out. 2009. ilus, tab
Article de Portugais | VETINDEX | ID: vti-7487

RÉSUMÉ

This investigation was carried out in beef cattle (n=219), sheep (n=55), and pampas deer (Ozotoceros bezoarticus) (n=49) from Nhecolândia, sub region of Brazilian Pantanal in Mato Grosso do Sul State, Brazil. It was aimed to assess the seropositivity of these species to bluetongue virus (BTV) by agar gel immunodiffusion test. Seropositivity rates were 42.0% for cattle and 10.9% for sheep. The pampas deer showed to be all seronegative. In cattle, seropositivity to BTV significantly increased with age (P<0.001). These data, the favorable environmental conditions to development of BTV vectors, and the bovine reproductive disorders reported by farmers may indicate that BTV infection occurrs in herds of Brazilian Pantanal, and probably induces to economical losses.(AU)


Sujet(s)
Animaux , Bovins , Virus de la langue bleue/isolement et purification , Épidémies de maladies , Avortement chez les animaux , Ceratopogonidae/virologie , Maladies endémiques/prévention et contrôle , Brésil/épidémiologie , Sérologie/méthodes , Ovis , Cervidae
11.
Arq. bras. med. vet. zootec ; Arq. bras. med. vet. zootec. (Online);61(5): 1222-1226, out. 2009. ilus, tab
Article de Portugais | LILACS | ID: lil-532037

RÉSUMÉ

This investigation was carried out in beef cattle (n=219), sheep (n=55), and pampas deer (Ozotoceros bezoarticus) (n=49) from Nhecolândia, sub region of Brazilian Pantanal in Mato Grosso do Sul State, Brazil. It was aimed to assess the seropositivity of these species to bluetongue virus (BTV) by agar gel immunodiffusion test. Seropositivity rates were 42.0% for cattle and 10.9% for sheep. The pampas deer showed to be all seronegative. In cattle, seropositivity to BTV significantly increased with age (P<0.001). These data, the favorable environmental conditions to development of BTV vectors, and the bovine reproductive disorders reported by farmers may indicate that BTV infection occurrs in herds of Brazilian Pantanal, and probably induces to economical losses.


Sujet(s)
Animaux , Bovins , Avortement chez les animaux , Ceratopogonidae/virologie , Épidémies de maladies , Virus de la langue bleue/isolement et purification , Brésil/épidémiologie , Cervidae , Maladies endémiques/prévention et contrôle , Ovis , Sérologie/méthodes
12.
Acta Trop ; 111(2): 102-7, 2009 Aug.
Article de Anglais | MEDLINE | ID: mdl-19467452

RÉSUMÉ

Determining the reservoir hosts for parasites is crucial for designing control measures, but it is often difficult to identify the role that each host species plays in maintaining the cycle of infection in the wild. One way to identify potential maintenance hosts is to estimate key parameters associated with transmission and pathogenicity. Here we assess the potential for three native rodent species of the Brazilian Pantanal (Clyomys laticeps, Thrichomys pachyurus and Oecomys mamorae) to act as reservoir or maintenance hosts of Trypanosoma evansi, an important parasite of domestic livestock. By analyzing blood parameters of naturally infected wild-caught rodents of these species, we compared their levels of parasitemia and anemia due to T. evansi infection with literature values for other host species infected by this parasite. We also analyzed levels of these blood parameters relative to infection by Trypanosoma cruzi, the causative agent of Chagas disease in humans, for which wild rodents are already thought to be important reservoir species. All three species showed low impacts of the two trypanosomes on their blood parameters compared to other species, suggesting that they experience a low virulence of trypanosome infection under natural conditions in the Pantanal and might act as maintenance hosts of trypanosome infections. The low parasitemia of trypanosome infections suggests that these rodents play a secondary role in the transmission cycle compared to other species, especially compared to the capybara (Hydrochaeris hydrochaeris) which also experiences low pathogenicity due to infection despite much higher levels of parasitemia.


Sujet(s)
Réservoirs de maladies/parasitologie , Rodentia/parasitologie , Trypanosoma/isolement et purification , Trypanosomiase/transmission , Anémie , Animaux , Sang/parasitologie , Brésil/épidémiologie , Parasitémie
13.
Trans R Soc Trop Med Hyg ; 102(11): 1133-9, 2008 Nov.
Article de Anglais | MEDLINE | ID: mdl-18541281

RÉSUMÉ

We have focused on the role played by a carnivore, the coati (Nasua nasua), in the transmission cycle of Trypanosoma cruzi in the Brazilian Pantanal biome. We collected data during 2000/01 and 2005-07. Prevalence and pattern of T. cruzi infection were determined by serological tests and hemoculture. Isolates were characterized by miniexon molecular assay. Our results demonstrate that T. cruzi transmission cycle among coatis in the southern Pantanal seems to be well established, as we found high serum prevalences and high parasitemias throughout the two studied periods. Single infections by TCII (32.1%), TCI (28.0%) and Z3 (7.1%) were observed. Mixed infections by TCI/TCII (10.7%) and TCI/Z3 (3.6%) were also detected. Distinct genotypes of T. cruzi could be recovered during the 8 months follow-up of the same animals. As free-living coatis have high densities and inhabit all habitats, they may play an important role in the maintenance and dispersion of the main T. cruzi subpopulations. Considering that the Pantanal connects some of the major biomes of South America, it may be acting as a corridor for the spread of the main T. cruzi subpopulations. Our data give support that predator-prey links are important mechanisms for T. cruzi transmission and perpetuation in the wild.


Sujet(s)
Maladie de Chagas/transmission , Réservoirs de maladies/médecine vétérinaire , Procyonidae/parasitologie , Trypanosoma cruzi/génétique , Animaux , Brésil/épidémiologie , Maladie de Chagas/épidémiologie , Maladie de Chagas/médecine vétérinaire , Réservoirs de maladies/parasitologie , Femelle , Variation génétique/génétique , Génotype , Mâle , Phylogenèse , Trypanosoma cruzi/isolement et purification
14.
Parasitol Res ; 103(3): 619-24, 2008 Aug.
Article de Anglais | MEDLINE | ID: mdl-18493795

RÉSUMÉ

The Brazilian Pantanal has been considered one of the richest and most diverse wetland ecosystems in the world. It is occupied by cattle ranching, and a variety of wildlife species share the same habitats with domestic livestock. We investigated infections of Trypanosoma evansi and Trypanosoma cruzi in the sympatric suiformes-collared peccary (Tayassu tajacu), white-lipped peccary (Tayassu pecari), and feral pig (Sus scrofa) by parasitological, serological, and molecular tests. Additionally, we evaluated the health status of both positive and negative suiformes by hematological and biochemical parameters. The results show that peccaries and feral pigs play an important role on the maintenance of both T. evansi and T. cruzi in the Brazilian Pantanal. Health impairment was observed only in the white-lipped peccary infected with T. evansi. Despite presenting low T. evansi parasitemia, all infected white-lipped peccaries displayed low hematocrit values and marked leucopenia. The hematological values showed that the T. evansi infection is more severe in young white-lipped peccaries. The presented data show that feral pigs and peccaries are immersed in the transmission net of both trypanosome species, T. cruzi and T. evansi, in the Pantanal region.


Sujet(s)
Chordés/parasitologie , Réservoirs de maladies , Sus scrofa/parasitologie , Trypanosoma/croissance et développement , Animaux , Brésil , Femelle , Hématocrite , Leucopénie , Mâle , Parasitémie , Zones humides
15.
Acta Trop ; 102(1): 55-62, 2007 Apr.
Article de Anglais | MEDLINE | ID: mdl-17451633

RÉSUMÉ

An evaluation was made on how the landscape and cattle ranching affect the transmission cycles and the patterns of tripanosomatid infection (Trypanosoma cruzi and Trypanosoma evansi) of small wild mammals in the Pantanal. This region comprises a large natural environment with a multiplicity of habitats, wide variety of biodiversity besides the presence of livestock. T. cruzi and T. evansi infections were evaluated by parasitological and serological methods in one preserved and one cattle ranching area. The diversity of the small mammal fauna showed to be the same in the two studied areas, however, their relative abundance was different. Distinct enzootiological scenarios of both trypanosomatids could be observed. Transmission of T. cruzi occurred mainly in forested areas, in the two study areas, while T. evansi occurred dispersed among all habitats studied in the unpreserved area. The arboreal rodent Oecomys mamorae, the most abundant species in both areas, displayed high T. cruzi and T. evansi serum prevalence and parasitemias. Also, the caviomorph rodent Thrichomys pachyurus was shown to be an important host due to its expressive relative abundance, prevalence of infection by both trypanosomatid species and a broad range use of habitats. The role of the small mammal fauna in the transmission cycle of both trypanosomes species seems to be distinct according to land use since we found a broad range of T. evansi infected hosts in the preserved area in contrast to cattle ranching area and a half number of the rodents species infected with T. cruzi in unpreserved in comparison to protect area. The present study showed that cattle ranching in this study area did not enhance overall prevalence of T. cruzi infection among small wild mammals. Together with the observation that small mammals diversity in FA is similar to RN area suggest that ranching activity may also not necessarily conduct to biodiversity loss or risk of Chagas disease.


Sujet(s)
Animaux sauvages/parasitologie , Maladie de Chagas/médecine vétérinaire , Écosystème , Marsupialia/parasitologie , Maladies des rongeurs/épidémiologie , Rodentia/parasitologie , Trypanosoma cruzi/isolement et purification , Trypanosoma/isolement et purification , Trypanosomiase/médecine vétérinaire , Élevage , Animaux , Anticorps antiprotozoaires/sang , Brésil/épidémiologie , Bovins , Maladie de Chagas/épidémiologie , Maladie de Chagas/parasitologie , Maladie de Chagas/transmission , Parasitémie/épidémiologie , Parasitémie/parasitologie , Parasitémie/médecine vétérinaire , Prévalence , Maladies des rongeurs/parasitologie , Trypanosoma/classification , Trypanosoma/immunologie , Trypanosoma cruzi/immunologie , Trypanosomiase/épidémiologie , Trypanosomiase/parasitologie , Trypanosomiase/transmission
16.
Vet Parasitol ; 125(3-4): 263-75, 2004 Nov 10.
Article de Anglais | MEDLINE | ID: mdl-15482883

RÉSUMÉ

In order to better understand the enzootiology of trypanosomiasis caused by Trypanosoma evansi in the Brazilian Pantanal we examined domestic and wild mammals by microhematocrit centrifuge technique (MHCT), immunofluorescence antibody test (IFAT) and polymerase chain reaction (PCR). T. evansi infection was detected in all species sampled with exception of the sheep and the feral pig. High parasitemias were observed in capybaras (5/24), coatis (18/115), horses (31/321) and dogs (3/112). Among these species, only the capybaras did not develop anemia. Low parasitemias, only detected by PCR, were found in buffaloes (18/43), bovines (29/331), marsupials (1/4), small rodents (14/67), bats (7/18), and one armadillo (1/8). The highest prevalence of T. evansi infection was recorded in horses (73%), although no neurological signs in infected horses were observed. Diagnosis through standard parasitological tests and IFAT should be used with caution since they may overlook comprovedly infected horses. The relationship between ranch management and T. evansi infection in horse was investigated. The importance of other transmission mechanisms apart from the tabanids and reservoir hosts are discussed.


Sujet(s)
Animaux domestiques/parasitologie , Animaux sauvages/parasitologie , Trypanosoma/croissance et développement , Trypanosomiase/médecine vétérinaire , Animaux , Anticorps antiprotozoaires/sang , Brésil/épidémiologie , ADN des protozoaires/composition chimique , ADN des protozoaires/génétique , Technique d'immunofluorescence directe/médecine vétérinaire , Hématocrite/médecine vétérinaire , Parasitémie/épidémiologie , Parasitémie/parasitologie , Parasitémie/médecine vétérinaire , Réaction de polymérisation en chaîne/médecine vétérinaire , Climat tropical , Trypanosoma/génétique , Trypanosomiase/épidémiologie , Trypanosomiase/parasitologie
17.
Vet Parasitol ; 117(1-2): 1-13, 2003 Nov 03.
Article de Anglais | MEDLINE | ID: mdl-14597273

RÉSUMÉ

Trypanosoma vivax and Trypanosoma evansi are livestock parasites of economic importance in Africa, Asia and South America. In the Pantanal, Brazil, they cause economic losses in both cattle and equines. Little is known of their maintenance and spread in nature, particularly in terms of reservoirs and means of mechanical transmission. Here we report for the first time the use of PCR for the detection of T. vivax and T. evansi in bovines, buffaloes and sheep. Whereas parasitological diagnosis detected only two T. vivax infections, one in buffalo and another in a cow, PCR detected infections in 34.8% buffaloes, 44.7% bovines and 37.3% sheep. Trypanozoon primers detected 41.8% infections in buffaloes and 8.1% in cattle. PCR revealed 6.9% mixed infections in buffaloes and 5.3% in cattle. The potential role of cattle and buffaloes as hosts and reservoirs of T. vivax is discussed, as well as the implications of possible extravascular foci in the maintenance of livestock trypanosomosis.


Sujet(s)
Buffles/parasitologie , Réaction de polymérisation en chaîne/médecine vétérinaire , Maladies des ovins/épidémiologie , Trypanosoma/isolement et purification , Trypanosomiase/médecine vétérinaire , Animaux , Brésil/épidémiologie , Bovins , ADN des protozoaires/analyse , Réservoirs de maladies/médecine vétérinaire , Réaction de polymérisation en chaîne/méthodes , Ovis , Maladies des ovins/diagnostic , Trypanosoma/génétique , Trypanosoma vivax/génétique , Trypanosoma vivax/isolement et purification , Trypanosomiase/diagnostic , Trypanosomiase/épidémiologie , Trypanosomose bovine/diagnostic , Trypanosomose bovine/épidémiologie
18.
Acta Trop ; 81(3): 203-10, 2002 Mar.
Article de Anglais | MEDLINE | ID: mdl-11835897

RÉSUMÉ

The course of an experimental Trypanosoma evansi infection in coatis (Nasua nasua, carnivora, Procyonidae) was followed for 262 days. Hematological analysis of the infected coatis revealed a marked decline in hemoglobin, packed-cell volume, and total erythrocyte count. An intense anemia followed the first wave of parasitemia and persisted until the end of the experimental period. Biochemical analysis showed increased serum levels of alanine aminotransferase and aspartate aminotransferase and decreased albumin. The main histopathological features consisted of myocarditis with the presence of degenerate cardiac fibers and meningoencephalitis. This study has shown that coatis infected with T. evansi develop a chronic disease.


Sujet(s)
Carnivora/parasitologie , Parasitoses animales/anatomopathologie , Trypanosoma , Trypanosomiase/médecine vétérinaire , Alanine transaminase/sang , Anémie/anatomopathologie , Anémie/médecine vétérinaire , Animaux , Aspartate aminotransferases/sang , Maladie chronique , Modèles animaux de maladie humaine , Méningoencéphalite/anatomopathologie , Méningoencéphalite/médecine vétérinaire , Myocardite/anatomopathologie , Myocardite/médecine vétérinaire , Myocarde/anatomopathologie , Parasitémie/médecine vétérinaire , Parasitoses animales/sang , Parasitoses animales/parasitologie , Sérumalbumine/analyse , Trypanosomiase/anatomopathologie
19.
Vet Parasitol ; 102(3): 209-16, 2001 Dec 13.
Article de Anglais | MEDLINE | ID: mdl-11777600

RÉSUMÉ

The course of Trypanosoma evansi infection in coatis (Carnivora, Procionidae) was followed for 262 days. Parasites were detected in all infected animals from day 2 post infection until the end of the study. No correlation between temperature and parasitemia was observed. Animals of the infected group demonstrated depression, weakness, lethargy and pale mucous membranes. Indirect fluorescent antibody tests detected anti-T. evansi antibodies within 7 to 14 days post infection and showed high levels until the end of the experimental period. The persistent parasitemia in coati and their relative tolerance to clinical signs suggested that this species develops a chronic disease and plays an important role in the epidemiology of trypanosomosis due to T. evansi in enzootic regions.


Sujet(s)
Anticorps antiprotozoaires/biosynthèse , Carnivora/parasitologie , Parasitémie/médecine vétérinaire , Trypanosomiase/médecine vétérinaire , Animaux , Anticorps antiprotozoaires/sang , État de porteur sain/immunologie , État de porteur sain/parasitologie , État de porteur sain/médecine vétérinaire , Maladie chronique , Réservoirs de maladies/médecine vétérinaire , Technique d'immunofluorescence indirecte/médecine vétérinaire , Parasitémie/immunologie , Parasitémie/parasitologie , Facteurs temps , Trypanosoma , Trypanosomiase/immunologie , Trypanosomiase/parasitologie
20.
Arq. bras. med. vet. zootec ; Arq. bras. med. vet. zootec. (Online);48(4): 485-9, ago. 1996. tab
Article de Portugais | LILACS | ID: lil-256986

RÉSUMÉ

O Trypanosoma evansi é um tripanosoma da secçäo salivaria pertencente ao subgênero Trypanozoon. Ele causa a "surra" no velho mundo e o "mal de caderas" na área subtropical da Argentina e no Pantanal, Brasil. Há similaridades entre as lesöes e patogenia causadas por T. brucei, T. evansi e T. equiperdum, inclusive no consumo de plaquetas na coagulaçäo intravascular disseminada (DIC). O presente estudo mostra os valores de APTT, PT e contagem de plaquetas evidenciando a DIC no primeiro relato de infecçäo natural pelo T. evansi em cäo no Pantanal, Brasil


Sujet(s)
Animaux , Chiens/parasitologie , Coagulation intravasculaire disséminée/médecine vétérinaire , Trypanosoma
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