ABSTRACT
Abstract In January 2018, a young male of Didelphis aurita (Wied-Neuwied, 1826), the Brazilian common opossum, was admitted for veterinary evaluation at the Recovery Clinic of Wild Animals of Estácio de Sá University, CRAS, in Rio de Janeiro, Brazil, due to the presence of a partially duplicated right hind limb. After x-ray evaluation, polymelia associated with syndactyly was diagnosed. The images revealed the following alterations on the right limb: single femur with increased diameter, two tibiae, two fibulae and absence of hallux. The observed malformations were restricted to the hind right limb, which remains functional. This is the first report of such anomalies in an individual of Didelphis aurita.
Resumo Em janeiro de 2018, um macho jovem de Didelphis aurita (Wied-Neuwied, 1826), o gambá-de-orelha-preta, foi recebido para atendimento veterinário na Clínica de Recuperação de Animais Silvestres (CRAS) da Universidade Estácio de Sá, no Rio de Janeiro, por ser portador de membro posterior direito parcialmente duplicado. Após exame radiográfico, constatou-se a ocorrência de polimelia associada a sindactilia. As imagens radiográficas revelaram as seguintes alterações no membro posterior direito: um fêmur com diâmetro aumentado, duas tíbias, duas fíbulas e ausência de hálux. As malformações observadas restringiram-se apenas ao membro posterior direito, o qual mantém sua funcionalidade. Essas alterações nunca antes foram descritas na espécie Didelphis aurita.
Subject(s)
Animals , Male , Syndactyly , Didelphis , BrazilABSTRACT
Brazilian spotted fever (BSF) is a highly lethal disease in southeastern Brazil. BSF is caused by the bacterium Rickettsia rickettsii and is transmitted by the bites of the tick of the genus Amblyomma. The spatial distribution of BSF risk areas is not well known in the country given the complexity of the transmission cycle. This study used the ecological niche modeling (ENM) approach to anticipate the potential distribution of the etiological agent (Rickettsia rickettsii), vectors (Amblyomma sculptum and A. dubitatum), and hosts (Hydrochoerus hydrochaeris, Didelphis aurita, and D. marsupialis) of BSF in Brazil. We compiled occurrence records for all vectors, hosts, and BSF from our own field surveillance, online repositories, and literature. ENM identified BSF risk areas in southeastern and southern Brazil, and anticipated other dispersed suitable areas in the western, central, and northeastern coast regions of Brazil. Tick vectors and mammalian hosts were confined to these same areas; however, host species showed broader suitability in northern Brazil. All species ENMs performed significantly better than random expectations. We also tested the BSF prediction based on 253 additional independent cases identified in our surveillance; the model anticipated 251 out of 253 of these independent cases. Background similarity tests comparing the ENMs of R. rickettsii, tick vectors, and mammalian hosts were unable to reject null hypotheses of niche similarity. Finally, we observed close coincidence between independent BSF cases, and areas suitable for combinations of vectors and hosts, reflecting the ability of these model pairs to anticipate the distribution of BSF cases across Brazil.
Subject(s)
Arthropod Vectors/microbiology , Didelphis/microbiology , Rickettsia rickettsii/isolation & purification , Rocky Mountain Spotted Fever/etiology , Rodentia/microbiology , Ticks/microbiology , Animals , Ecosystem , Rocky Mountain Spotted Fever/transmissionABSTRACT
The increasing appearance of Chagas disease insect vectors in the metropolitan region of São Paulo has led endemic control entities to be alarmed at the potential increase in the number of cases of the disease. Trypanosoma cruzi is a flagellated protozoan responsible of trypanosomiasis, which has as the main vectors hematophagous triatomines. In the recently reported colonies of Panstrongylus infestans in urban areas around São Paulo, most of them are carrying the protozoan. Mammals of the orders, Didelphimorphia and Cingulata are known as primitive reservoirs of T. cruzi, which is also found in Primates and Chiroptera. It is suggested that the dissemination of the protozoan to other species has occurred through predation and direct contact with physiological secretions contained in mucous membranes and lesions, since the secretions contained in paracloacal glands of marsupials are also an important contaminant material. The objective of this study were investigate the possible presence of the protozoan T. cruzi in blood samples of the Neotropical marsupial Didelphis aurita in the park of Instituto Butantan. For the analysis of hemoparasites, blood samples were collected from the caudal vein for 7 animals. The analysis were made with blood smears on histological slides fixed in methyl alcohol, and stained by the Giemsa method for observation by microscopy. No positive results were obtained for T. cruzi after analyzing the samples collected.
Com o crescente aparecimento de insetos vetores de doença de Chagas na região metropolitana de São Paulo, entidades de controle de endemias se alarmaram para o potencial aumento dos casos da doença em municípios da Grande São Paulo. O Trypanosoma cruzi é um protozoário flagelado responsável pela tripanossomíase, doença que possui como principais vetores os triatomíneos hematófagos. Recentemente, há relatos do aumento de colônias de Panstrongylus megistus nos municípios próximos a São Paulo, sendo que em grande parte deles foi encontrado o protozoário. Sabe-se que mamíferos das ordens Marsupialia e Cingulata são reservatórios primitivos do protozoário, havendo também registros em Primatas e Chiroptera. Sugere-se que a disseminação do protozoário para outras espécies tenha ocorrido através da predação e contato direto com secreções fisiológicas contidas em mucosas e lesões, sendo as secreções contidas nas glândulas paracloacais também um importante material contaminante. Este trabalho objetivou pesquisar o protozoário Trypanosoma cruzi nas amostras de sangue de Didelphis aurita do parque do Instituto Butantan Para a análise dos hemoparasitas, foram coletadas amostras de sangue da veia caudal. A análise foi feita a partir de esfregaço sanguíneo feito em lâminas histológicas fixadas em álcool metílico, sendo coradas pelo método Giemsa, e observadas através de microscopia óptica. Não foram obtidos resultados positivos para T. cruzi após a análise das amostras coletadas.
ABSTRACT
Abstract Erlichiosis affects humans and animals worldwide. Its distribution and prevalence depends on the presence of tick vectors and hosts in one geographic area. The aim of the present study was to investigate the occurrence of Ehrlichia spp. and Anaplasma spp. in opossums (Didelphis sp.) from the State of Rio de Janeiro, southeast Brazil. Blood samples from 37 animals were tested for these two pathogens using molecular methods. One animal (2.7%) was positive for Ehrlichia sp. by 16S rRNA-based nested PCR. In a phylogenetic analysis based on the 16S rRNA gene using the maximum likelihood method and the GTRGAMMA+I evolutionary model, we detected a novel Ehrlichia sp. genotype closely related to genotypes of E. canis previously reported in dogs from Brazil. To the authors' knowledge, this is the first molecular detection of Ehrlichia sp. in opossums from this State in the southeastern region of the country.
Resumo A erliquiose afeta seres humanos e animais em todo o mundo. Sua distribuição e prevalência dependem da presença de vetores de carrapatos e hospedeiros em uma área geográfica. O objetivo do presente estudo foi investigar a ocorrência de Ehrlichia sp. e Anaplasma sp. em gambás (Didelphis sp.) do Estado do Rio de Janeiro, sudeste do Brasil. Amostras de sangue de 37 animais foram testadas para estes dois patógenos usando métodos moleculares. Um animal (2,7%) foi positivo para Ehrlichia sp. baseado em 16S rRNA-nested PCR. Em uma análise filogenética baseada no gene 16S rRNA usando o método de máxima verossimilhança e o modelo evolutivo GTRGAMMA + I, detectamos um novo genótipo de Ehrlichia sp. intimamente relacionado a genótipos de E. canis previamente relatados em cães do Brasil. Para o conhecimento dos autores, esta é a primeira detecção molecular de Ehrlichia sp. em gambás deste estado na região sudeste do país.
Subject(s)
Animals , Female , Didelphis/microbiology , Ehrlichia/isolation & purification , Anaplasma/isolation & purification , Phylogeny , Brazil , RNA, Ribosomal, 16S/genetics , Polymerase Chain Reaction , Ehrlichia/genetics , Anaplasma/geneticsABSTRACT
Associations with environmental and host parameters were assessed to describe tick parasitism patterns in two medium-sized mammals of the Atlantic rainforest region of Argentina. Ticks found on 93 specimens of Nasua nasua and 26 specimens of Didelphis aurita captured at six sites in the Iguazú National Park were collected. Generalized linear models were constructed to explain the presence and abundance of ticks and the most appropriate ones were selected after stepwise simplification. The season, site and host body mass variables were important to explain the abundance of Amblyomma coelebs nymphs, while site was important to describe larval abundance of this species. Season was the most important variable for larvae and nymphs of Haemaphysalis juxtakochi, while Amblyomma brasiliense nymphs were associated with host age. Amblyomma ovale larvae were related to host age, and adult ticks with host sex. The results indicate that these medium-sized mammals are important to support the immature tick stages and that both host and environmental factors may be associated with parasite loads.
Subject(s)
Didelphis , Ixodidae/physiology , Procyonidae , Tick Infestations/epidemiology , Animals , Argentina/epidemiology , Female , Ixodidae/growth & development , Larva/growth & development , Larva/physiology , Male , Nymph/growth & development , Nymph/physiology , Prevalence , Tick Infestations/parasitologyABSTRACT
BACKGROUND Didelphis spp. are a South American marsupial species that are among the most ancient hosts for the Trypanosoma spp. OBJECTIVES We characterise a new species (Trypanosoma janseni n. sp.) isolated from the spleen and liver tissues of Didelphis aurita in the Atlantic Rainforest of Rio de Janeiro, Brazil. METHODS The parasites were isolated and a growth curve was performed in NNN and Schneider's media containing 10% foetal bovine serum. Parasite morphology was evaluated via light microscopy on Giemsa-stained culture smears, as well as scanning and transmission electron microscopy. Molecular taxonomy was based on a partial region (737-bp) of the small subunit (18S) ribosomal RNA gene and 708 bp of the nuclear marker, glycosomal glyceraldehyde-3-phosphate dehydrogenase (gGAPDH) genes. Maximum likelihood and Bayesian inference methods were used to perform a species coalescent analysis and to generate individual and concatenated gene trees. Divergence times among species that belong to the T. cruzi clade were also inferred. FINDINGS In vitro growth curves demonstrated a very short log phase, achieving a maximum growth rate at day 3 followed by a sharp decline. Only epimastigote forms were observed under light and scanning microscopy. Transmission electron microscopy analysis showed structures typical to Trypanosoma spp., except one structure that presented as single-membraned, usually grouped in stacks of three or four. Phylogeography analyses confirmed the distinct species status of T. janseni n. sp. within the T. cruzi clade. Trypanosoma janseni n. sp. clusters with T. wauwau in a well-supported clade, which is exclusive and monophyletic. The separation of the South American T. wauwau + T. janseni coincides with the separation of the Southern Super Continent. CONCLUSIONS This clade is a sister group of the trypanosomes found in Australian marsupials and its discovery sheds light on the initial diversification process based on what we currently know about the T. cruzi clade.
Subject(s)
Humans , Trypanosoma , Trypanosomatina , Didelphis/classification , Phylogeography , BrazilABSTRACT
DM64 is a glycosylated protein with antivenom activity isolated from the serum of the opossum Didelphis aurita. It binds non-covalently to myotoxins I (Asp49) and II (Lys49) from Bothrops asper venom and inhibits their myotoxic effect. In this study, an affinity column with immobilized DM64 as bait was used to fish potential target toxins. All ten isolated myotoxins tested were able to effectively bind to the DM64 column. To better access the specificity of the inhibitor, crude venoms from Bothrops (8 species), Crotalus (2 species) and Naja naja atra were submitted to the affinity purification. Venom fractions bound and nonbound to the DM64 column were analyzed by two-dimensional gel electrophoresis and MALDI-TOF/TOF MS. Although venom fractions bound to the column were mainly composed of basic PLA2, a few spots corresponding to acidic PLA2 were also observed. Some unexpected protein spots were also identified: C-type lectins and CRISP may represent putative new targets for DM64, whereas the presence of serine peptidases in the venom bound fraction is likely a consequence of nonspecific binding to the column matrix. The present results contribute to better delineate the inhibitory potential of DM64, providing a framework for the development of more specific antivenom therapies. BIOLOGICAL SIGNIFICANCE: Local tissue damage induced by myotoxic PLA2 remains a serious consequence of snake envenomation, since it is only partially neutralized by traditional antivenom serotherapy. Myotoxin inhibition by highly specific molecules offers great promise in the treatment of snakebites, a health problem largely neglected by governments and pharmaceutical industries. Bioactive compounds such as DM64 can represent a valuable source of scaffolds for drug development in this area. The present study has systematically profiled the binding specificity of DM64 toward a variety of snake venom toxin classes and therefore can lead to a better understanding of the structure-function relationship of this important antivenom protein.
Subject(s)
Blood Proteins/metabolism , Crotalid Venoms/antagonists & inhibitors , Animals , Blood Proteins/therapeutic use , Chromatography, Affinity , Electrophoresis, Gel, Two-Dimensional , Phospholipases A/analysis , Phospholipases A/antagonists & inhibitors , Protein Binding , Proteomics/methods , Species Specificity , Tandem Mass Spectrometry , Toxins, Biological/analysis , Toxins, Biological/antagonists & inhibitorsABSTRACT
Abstract Erlichiosis affects humans and animals worldwide. Its distribution and prevalence depends on the presence of tick vectors and hosts in one geographic area. The aim of the present study was to investigate the occurrence of Ehrlichia spp. and Anaplasma spp. in opossums (Didelphis sp.) from the State of Rio de Janeiro, southeast Brazil. Blood samples from 37 animals were tested for these two pathogens using molecular methods. One animal (2.7%) was positive for Ehrlichia sp. by 16S rRNA-based nested PCR. In a phylogenetic analysis based on the 16S rRNA gene using the maximum likelihood method and the GTRGAMMA+I evolutionary model, we detected a novel Ehrlichia sp. genotype closely related to genotypes of E. canis previously reported in dogs from Brazil. To the authors knowledge, this is the first molecular detection of Ehrlichia sp. in opossums from this State in the southeastern region of the country.
Resumo A erliquiose afeta seres humanos e animais em todo o mundo. Sua distribuição e prevalência dependem da presença de vetores de carrapatos e hospedeiros em uma área geográfica. O objetivo do presente estudo foi investigar a ocorrência de Ehrlichia sp. e Anaplasma sp. em gambás (Didelphis sp.) do Estado do Rio de Janeiro, sudeste do Brasil. Amostras de sangue de 37 animais foram testadas para estes dois patógenos usando métodos moleculares. Um animal (2,7%) foi positivo para Ehrlichia sp. baseado em 16S rRNA-nested PCR. Em uma análise filogenética baseada no gene 16S rRNA usando o método de máxima verossimilhança e o modelo evolutivo GTRGAMMA + I, detectamos um novo genótipo de Ehrlichia sp. intimamente relacionado a genótipos de E. canis previamente relatados em cães do Brasil. Para o conhecimento dos autores, esta é a primeira detecção molecular de Ehrlichia sp. em gambás deste estado na região sudeste do país.
ABSTRACT
Abstract In January 2018, a young male of Didelphis aurita (Wied-Neuwied, 1826), the Brazilian common opossum, was admitted for veterinary evaluation at the Recovery Clinic of Wild Animals of Estácio de Sá University, CRAS, in Rio de Janeiro, Brazil, due to the presence of a partially duplicated right hind limb. After x-ray evaluation, polymelia associated with syndactyly was diagnosed. The images revealed the following alterations on the right limb: single femur with increased diameter, two tibiae, two fibulae and absence of hallux. The observed malformations were restricted to the hind right limb, which remains functional. This is the first report of such anomalies in an individual of Didelphis aurita.
Resumo Em janeiro de 2018, um macho jovem de Didelphis aurita (Wied-Neuwied, 1826), o gambá-de-orelha-preta, foi recebido para atendimento veterinário na Clínica de Recuperação de Animais Silvestres (CRAS) da Universidade Estácio de Sá, no Rio de Janeiro, por ser portador de membro posterior direito parcialmente duplicado. Após exame radiográfico, constatou-se a ocorrência de polimelia associada a sindactilia. As imagens radiográficas revelaram as seguintes alterações no membro posterior direito: um fêmur com diâmetro aumentado, duas tíbias, duas fíbulas e ausência de hálux. As malformações observadas restringiram-se apenas ao membro posterior direito, o qual mantém sua funcionalidade. Essas alterações nunca antes foram descritas na espécie Didelphis aurita.
ABSTRACT
Nematode parasites of the cardiopulmonary system of livestock and pet animals have been receiving attention due to the pathogenic effects they produce in the course of the infection. However, parasitism in wild animals by metastrongilid nematodes has been neglected, resulting in potential risk to wildlife. Heterostrongylus heterostrongylus is the etiological agent of bronchial pneumonia in the black-eared opossum, Didelphis aurita, a widely distributed marsupial frequently reported to inhabit areas from wild environments to peri-urban spaces. In this study, we reassessed the taxonomy of H. heterostrongylus, describing and comparing morphology of L1 and L3 larvae and adult worms with closely related angiostrongilids, and inferring phylogenetic affinities within the family Angiostrongylidae; we also detailed histopathological reactions under natural infection. Ultrastructural morphology and light microscopy confirmed cephalic structures with well-developed trilobed lips, patterns of caudal bursa rays, spicules shape, terminal anal aperture and presence of the ventral protuberance in L3 larvae, characteristics present for the family Angiostrongylidae. Our molecular phylogenetic analyses, based on the partial small subunit (SSU) 18S rRNA gene, suggested that H. heterostrongylus and Didelphostrongylus hayesi are closely related. Pathological analyses agreed with previous findings, showing that cardiopulmonary parasitism provokes verminous pneumonia and mucous bronchiolitis with hypertrophy of the smooth bronchiolar muscle. These data confirmed that H. heterostrongylus represents a pulmonary pathogen in D. aurita, produces severe pathological effects, and may represent risk to domestic and wild animals.
Subject(s)
Didelphis/parasitology , Metastrongyloidea/classification , Strongylida Infections/veterinary , Animals , DNA, Helminth/chemistry , DNA, Helminth/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Female , Lung/parasitology , Lung/pathology , Male , Metastrongyloidea/genetics , Metastrongyloidea/isolation & purification , Metastrongyloidea/ultrastructure , Microscopy, Electron, Scanning/veterinary , Phylogeny , Sequence Analysis, DNA , South America , Strongylida Infections/diagnosis , Strongylida Infections/parasitologyABSTRACT
Abstract This work involved a serological investigation of tick-borne pathogens in opossums in eight municipalities of the state of São Paulo, Brazil. Serum samples from 109 opossums (91 Didelphis aurita and 18 Didelphis albiventris) were tested to detect antibodies to Rickettsia rickettsii (Taiaçu strain, 1:64 cut-off) and Ehrlichia canis (São Paulo strain, 1:40 cut-off), by indirect immunofluorescence assay (IFA); and against Borrelia burgdorferi (strain G39/40) by enzyme-linked immunosorbent assay (ELISA). The presence of antibodies to anti-R. rickettsii, anti-E. canis and anti-B. burgdorferi was detected in 32 (29.35%), 16 (14.67%) and 30 (27.52%) opossums, respectively. Opossum endpoint titers ranged from 64 to 1,024 for R. rickettsii, from 40 to 160 for E. canis, and from 400 to >51,200 for B. burgdorferi. These serological results suggest that opossums have been exposed to Rickettsia spp., Ehrlichia spp., and B. burgdorferi-related agents in the state of São Paulo. Our study underscores the need for further research about these agents in this study area, in view of the occurrence of Spotted Fever and Baggio-Yoshinari Syndrome disease in humans in the state of São Paulo, Brazil.
Resumo O presente estudo investigou evidência sorológica de agentes transmitidos por carrapatos em gambás em oito municípios do Estado de São Paulo, Brasil. Amostras de soro de 109 gambás (91 Didelphis aurita e 18 Didelphis albiventris) foram testadas para detecção de anticorpos contra Rickettsia rickettsii (cepa Taiaçu, ponto de corte 1:64) Ehrlichia canis (cepa São Paulo, ponto de corte 1:40), pela reação de imunofluorescência indireta (RIFI); e contra Borrelia burgdorferi (cepa G39/40) pelo teste imunoenzimático (ELISA). A presença de anticorpos anti-R. rickettsii, anti-E. canis e anti-B. burgdorferi foi detectada em 32 (29,35%), 16 (14,67%) e 30 (27,52%) gambás, respectivamente. Os títulos finais variaram de 64 a 1.024 para R. rickettsii, de 40 a 160 para E. canis, e de 400 a >51.200 para B. burgdorferi. Esses resultados sugerem que os gambás foram expostos a agentes relacionados à Rickettsia spp., Ehrlichia spp., e B. burgdorferi no Estado de São Paulo. Neste estudo salienta a necessidade de novas pesquisas sobre esses agentes nessas áreas de trabalho, devido à ocorrência da Febre Maculosa e da Síndrome Baggio-Yoshinari em humanos no Estado de São Paulo, Brasil.
