RESUMEN
A comprehensive investigation, incorporating both morphological and molecular analyses, has unveiled the existence of a hitherto unknown nematode species, Paracapillaria (Ophidiocapillaria) siamensis sp. nov., residing in the intestine of the monocled cobra, Naja kaouthia, in the central region of Thailand. This study integrates morphological characteristics, morphometric examination, scanning electron microscopy and molecular phylogenetic analysis (COI, 18S rRNA and ITS1 genes). The findings place the newly described species within the subgenus Ophidiocapillaria, elucidating its distinctive characteristics, including a frame-like proximal spicule shape, approximate lengths of 19 000 and 22 500 µm with approximate widths of 90 and 130 µm for males and females, 39â45 stichocytes, elevated lips without protrusion, a dorsal bacillary band stripe with an irregular pattern of bacillary cells and evidence of intestinal infection. These features serve to differentiate it from other species within the same subgenus, notably Paracapillaria (Ophidiocapillaria) najae De, , a species coexisting P. siamensis sp. nov. in the monocled cobra from the same locality. This study addresses the co-infection of the novel species and P. najae within the same snake host, marking the second documented instance of a paracapillariid species in the monocled cobra within the family Elapidae. The genetic characterization supports the formal recognition of P. siamensis sp. nov. as a distinct species, thereby underscoring its taxonomic differentiation within the Capillariidae family. This research identifies and characterizes the new nematode species, contributing valuable insights into the taxonomy of this nematode.
Asunto(s)
Filogenia , Animales , Tailandia , Masculino , Femenino , Microscopía Electrónica de Rastreo/veterinaria , ARN Ribosómico 18S/genética , ARN Ribosómico 18S/análisis , Naja , Nematodos/clasificación , Nematodos/ultraestructura , Nematodos/genética , Nematodos/anatomía & histología , Intestinos/parasitología , ADN de HelmintosRESUMEN
The parasitic nematode Paracapillaria (Ophidiocapillaria) najae De, 1998, found in the Indian cobra Naja naja is redescribed and re-illustrated in the present study. The monocled cobra Naja kaouthia was discovered to be a new host for this parasite in central Thailand. A comprehensive description extending the morphological and molecular characteristics of the parasites is provided to aid species recognition in future studies. The morphometric characters of 41 parasites collected from 5 cobra specimens are compared with those described in the original studies. Phylogenetic analyses using mitochondrial cytochrome c oxidase subunit 1 and nuclear 18S ribosomal RNA genes were performed to provide novel information on the systematics of P. najae. Similar characteristics were observed in the examined nematode samples, despite being found in different hosts, confirming their identity as P. najae. The molecular genetic results support the species status of P. najae, indicating P. najae is well defined and separated from other related nematode species in the family Capillariidae. Morphological descriptions, genetic sequences, evolutionary relationships among capillariids and new host and distribution records of P. najae are discussed. Paracapillaria najae specimens found in the Thai cobra had some morphological variation, and sexual size dimorphism was also indicated. Paracapillaria najae was found to infect various cobra host species and appeared to be common throughout the Oriental regions, consistent with its hosts' distribution.
Asunto(s)
Helmintos , Naja naja , Animales , Venenos Elapídicos/análisis , Tailandia , Antivenenos , Trichuroidea , Filogenia , ElapidaeRESUMEN
Gastrointestinal helminth infection likely affects the gut microbiome, in turn affecting host health. To investigate the effect of intestinal parasite status on the gut microbiome, parasitic infection surveys were conducted in communities in Nan Province, Thailand. In total, 1047 participants submitted stool samples for intestinal parasite examination, and 391 parasite-positive cases were identified, equating to an infection prevalence of 37.3%. Intestinal protozoan species were less prevalent (4.6%) than helminth species. The most prevalent parasite was the minute intestinal fluke Haplorchis taichui (35.9%). Amplicon sequencing of 16S rRNA was conducted to investigate the gut microbiome profiles of H. taichui-infected participants compared with those of parasite-free participants. Prevotella copri was the dominant bacterial operational taxonomic unit (OTU) in the study population. The relative abundance of three bacterial taxa, Ruminococcus, Roseburia faecis and Veillonella parvula, was significantly increased in the H. taichui-infected group. Parasite-negative group had higher bacterial diversity (α diversity) than the H. taichui-positive group. In addition, a significant difference in bacterial community composition (ß diversity) was found between the two groups. The results suggest that H. taichui infection impacts the gut microbiome profile by reducing bacterial diversity and altering bacterial community structure in the gastrointestinal tract.
Asunto(s)
Bacterias/aislamiento & purificación , Microbioma Gastrointestinal , Parasitosis Intestinales/complicaciones , Población Rural , Trematodos/fisiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Tailandia , Adulto JovenRESUMEN
In 2018, extensive field studies of diversity and prevalence of helminth infection in synanthropic rodents and non-rodent small mammals from public parks and citified areas in the Bangkok Metropolitan were conducted. Rattus rattus complex was the dominant small mammal in public parks. Of the 197 animals, 147 individuals were infected with one or more species of helminths, yielding an infection prevalence of 74.6%. Twenty-five species of helminths were recovered during necropsy. Pterygodermatites tani was the most prevalent (36.2%); other encountered species included Raillietina celebensis, Hydatigera taeniaformis (metacestode in liver tissue), Gongylonema neoplasticum and Hymenolepis diminuta. Different helminth assemblages infected three different host taxa, i.e. synanthropic Rattus spp., Tupaia belangeri (Northern treeshrew) and Suncus murinus (Asian house shrew). Nine species of possible zoonotic helminths were identified. The focus on synanthropic rats influenced the findings of helminth diversity by either host intrinsic or extrinsic factors. A significant positive correlation was found between host body mass and helminth species richness. Greater helminth species richness was found in rats from public parks compared with animals from citified areas (e.g. inside buildings or offices). Also, helminth species richness was negatively correlated with the proportion of post-flooding/rain-fed land. These results provide essential information for assessing the incidence of potential zoonotic health threats in Bangkok and updating research in parasite ecology.
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Biota , Helmintiasis Animal/parasitología , Helmintos/clasificación , Enfermedades de los Roedores/parasitología , Roedores/parasitología , Animales , Ciudades , Inundaciones , Helmintiasis Animal/epidemiología , Helmintos/aislamiento & purificación , Humanos , Parques Recreativos , Prevalencia , Ratas , Enfermedades de los Roedores/epidemiología , Musarañas/parasitología , Tailandia/epidemiologíaRESUMEN
The reduction in biodiversity from land use change due to urbanization and agricultural intensification appears to be linked to major epidemiological changes in many human diseases. Increasing disease risks and the emergence of novel pathogens result from increased contact among wildlife, domesticated animals, and humans. We investigated the relationship between human alteration of the environment and the occurrence of generalist and synanthropic rodent species in relation to the diversity and prevalence of rodent-borne pathogens in Southeast Asia, a hotspot of threatened and endangered species, and a foci of emerging infectious diseases. We used data from an extensive pathogen survey of rodents from seven sites in mainland Southeast Asia in conjunction with past and present land cover analyses. At low spatial resolutions, we found that rodent-borne pathogen richness is negatively associated with increasing urbanization, characterized by increased habitat fragmentation, agriculture cover and deforestation. However, at a finer spatial resolution, we found that some major pathogens are favored by environmental characteristics associated with human alteration including irrigation, habitat fragmentation, and increased agricultural land cover. In addition, synanthropic rodents, many of which are important pathogen reservoirs, were associated with fragmented and human-dominated landscapes, which may ultimately enhance the opportunities for zoonotic transmission and human infection by some pathogens.
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Enfermedades de los Roedores , Animales , Asia Sudoriental , Biodiversidad , Ecosistema , Humanos , RoedoresRESUMEN
The presence of Neospora caninum Dubey, Carpenter, Speer, Topper et Uggla, 1988 in small mammals (i.e. murid rodents, Erinaceomorpha, Eulipotyphla and Scadentia) was explored for first time in South-East Asia. A total of 192 individuals from six localities across Thailand were analysed. A general prevalence of N. caninum of 22% was observed, with some variation among localities (5-36%). Four main types of habitat were included and rodents trapped in dry-land habitat (17 positive among 41 individuals) were more likely to be infected with N. caninum than those from other habitats (forest, rain-fed land and settlement). Rodent species identity and individual rodent weight had no influence on individual infection. Our results provided the first data on the presence of N. caninum in rodents in South-East Asia and first report of N. caninum in the order Scadentia.
Asunto(s)
Coccidiosis/veterinaria , Erizos , Neospora/aislamiento & purificación , Enfermedades de los Roedores/epidemiología , Roedores , Tupaia , Animales , Coccidiosis/epidemiología , Coccidiosis/parasitología , Ecosistema , Prevalencia , Enfermedades de los Roedores/parasitología , Tailandia/epidemiologíaRESUMEN
More than a dozen Gongylonema spp. (Spirurida: Spiruroidea: Gongylonematidae) have been described from a variety of rodent hosts worldwide. Gongylonema neoplasticum (Fibiger & Ditlevsen, 1914), which dwells in the gastric mucosa of rats such as Rattus norvegicus (Berkenhout) and Rattus rattus (Linnaeus), is currently regarded as a cosmopolitan nematode in accordance with global dispersion of its definitive hosts beyond Asia. To facilitate the reliable specific differentiation of local rodent Gongylonema spp. from the cosmopolitan congener, the genetic characterisation of G. neoplasticum from Asian Rattus spp. in the original endemic area should be considered since the morphological identification of Gongylonema spp. is often difficult due to variations of critical phenotypical characters, e.g. spicule lengths and numbers of caudal papillae. In the present study, morphologically identified G. neoplasticum from 114 rats of seven species from Southeast Asia were selected from archived survey materials from almost 4,500 rodents: Thailand (58 rats), Cambodia (52 rats), Laos (three rats) and Philippines (one rat). In addition, several specimens from four rats in Indonesia were used in the study. Nucleotide sequences of the ribosomal RNA gene (rDNA) (5,649 bp) and the cytochrome c oxidase subunit 1 gene (cox1) (818 bp) were characterised. The rDNA showed little nucleotide variation, including the internal transcribed spacer (ITS) regions. The cox1 showed 24 haplotypes, with up to 15 (1.83%) nucleotide substitutions regardless of parasite origin. Considering that Rattus spp. have been shown to originate from the southern region of Asia and G. neoplasticum is their endogenous parasite, it is reasonable to propose that the present study covers a wide spectrum of the genetic diversity of G. neoplasticum, useful for both the molecular genetic speculation of the species and the molecular genetic differentiation of other local rodent Gongylonema spp. from the cosmopolitan congener.
Asunto(s)
Variación Genética , Ratas/parasitología , Spiruroidea/clasificación , Spiruroidea/genética , Animales , Asia Sudoriental , ADN Ribosómico/genética , Complejo IV de Transporte de Electrones/genética , Especificidad de la EspecieRESUMEN
A field survey studying intestinal parasites in humans and microbial pathogen contamination at environment was performed in a Laotian rural village to identify potential risks for disease outbreaks. A parasitological investigation was conducted in Ban Lak Sip village, Luang Prabang, Lao PDR involving fecal samples from 305 inhabitants as well as water samples taken from 3 sites of the local stream. Water analysis indicated the presence of several enteric pathogens, i.e., Aeromonas spp., Vibrio spp., E. coli H7, E. coli O157: H7, verocytotoxin-producing E. coli (VTEC), Shigella spp., and enteric adenovirus. The level of microbial pathogens contamination was associated with human activity, with greater levels of contamination found at the downstream site compared to the site at the village and upstream, respectively. Regarding intestinal parasites, the prevalence of helminth and protozoan infections were 68.9% and 27.2%, respectively. Eight helminth taxa were identified in fecal samples, i.e., 2 tapeworm species (Taenia sp. and Hymenolepis diminuta), 1 trematode (Opisthorchis sp.), and 5 nematodes (Ascaris lumbricoides, Trichuris trichiura, Strongyloides stercoralis, trichostrongylids, and hookworms). Six species of intestinal protists were identified, i.e., Blastocystis hominis, Cyclospora spp., Endolimax nana, Entamoeba histolytica/E. dispar, Entamoeba coli, and Giardia lamblia. Questionnaires and interviews were also conducted to determine risk factors of infection. These analyses together with a prevailing infection level suggested that most of villagers were exposed to parasites in a similar degree due to limited socio-economic differences and sharing of similar practices. Limited access to effective public health facilities is also a significant contributing factor.
Asunto(s)
Brotes de Enfermedades , Parasitosis Intestinales/epidemiología , Parasitosis Intestinales/parasitología , Microbiología del Agua , Contaminación del Agua , Adolescente , Adulto , Niño , Heces/parasitología , Femenino , Humanos , Parasitosis Intestinales/etiología , Laos/epidemiología , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Población Rural/estadística & datos numéricos , Encuestas y Cuestionarios , Adulto JovenRESUMEN
Chigger mites of Thailand were studied on the basis of larvae collected from 19 small mammal species (17 species of Rodentia, 1 species of Erinaceomorpha, and 1 species of Scandentia) and revision of published data. Samples of 38 trombiculid species were collected from 11 provinces. Three new species were described: Trombiculindus kosapani sp. nov., Helenicula naresuani sp. nov., and Walchia chavali sp. nov. Ten species were recorded in Thailand for the first time: Leptotrombidium sialkotense Vercammen-Grandjean and Langston, 1976; Leptotrombidium subangulare Wen and Xiang, 1984; Leptotrombidium tenompaki Stekolnikov, 2013; Leptotrombidium turdicola Vercammen-Grandjean and Langston, 1976; Leptotrombidium yunlingense Yu, Yang, Zhang and Hu, 1981; Lorillatum hekouensis Yu, Chen and Lin, 1996; Helenicula pilosa (Abonnenc and Taufflieb, 1957); Gahrliepia xiaowoi Wen and Xiang, 1984; Walchia minuscuta Chen, 1978; and Walchia ventralis (Womersley, 1952). In all, 99 chigger mite species were considered; the presence of 93 species was established in Thailand by original data or properly documented records in the scientific literature. Evidence for 64 species records of 147 from a previous checklist of Thai chiggers (Tanskul 1993) remains unknown. Distribution of chigger species by geographical regions of Thailand is discussed.
Asunto(s)
Biodiversidad , Lista de Verificación , Mamíferos/parasitología , Trombiculidae/clasificación , Animales , Tailandia , Trombiculidae/anatomía & histologíaRESUMEN
1. While the effects of deforestation and habitat fragmentation on parasite prevalence or richness are well investigated, host-parasite networks are still understudied despite their importance in understanding the mechanisms of these major disturbances. Because fragmentation may negatively impact species occupancy, abundance and co-occurrence, we predict a link between spatiotemporal changes in habitat and the architecture of host-parasite networks. 2. For this, we used an extensive data set on 16 rodent species and 29 helminth species from seven localities of South-East Asia. We analysed the effects of rapid deforestation on connectance and modularity of helminth-parasite networks. We estimated both the degree of fragmentation and the rate of deforestation through the development of land uses and their changes through the last 20 to 30 years in order to take into account the dynamics of habitat fragmentation in our statistical analyses. 3. We found that rapid fragmentation does not affect helminth species richness per se but impacts host-parasite interactions as the rodent-helminth network becomes less connected and more modular. 4. Our results suggest that parasite sharing among host species may become more difficult to maintain with the increase of habitat disturbance.
Asunto(s)
Biodiversidad , Helmintiasis Animal/epidemiología , Helmintos/fisiología , Interacciones Huésped-Parásitos , Muridae , Enfermedades de los Roedores/epidemiología , Animales , Cambodia/epidemiología , Ecosistema , Sistemas de Información Geográfica , Helmintiasis Animal/parasitología , Laos/epidemiología , Prevalencia , Enfermedades de los Roedores/parasitología , Nave Espacial , Tailandia/epidemiologíaRESUMEN
A dataset of bacterial diversity found in mites was compiled from 193 publications (from 1964 to January 2015). A total of 143 mite species belonging to the 3 orders (Mesostigmata, Sarcoptiformes and Trombidiformes) were recorded and found to be associated with approximately 150 bacteria species (in 85 genera, 51 families, 25 orders and 7 phyla). From the literature, the intracellular symbiont Cardinium, the scrub typhus agent Orientia, and Wolbachia (the most prevalent symbiont of arthropods) were the dominant mite-associated bacteria, with approximately 30 mite species infected each. Moreover, a number of bacteria of medical and veterinary importance were also reported from mites, including species from the genera Rickettsia, Anaplasma, Bartonella, Francisella, Coxiella, Borrelia, Salmonella, Erysipelothrix and Serratia. Significant differences in bacterial infection patterns among mite taxa were identified. These data will not only be useful for raising awareness of the potential for mites to transmit disease, but also enable a deeper understanding of the relationship of symbionts with their arthropod hosts, and may facilitate the development of intervention tools for disease vector control. This review provides a comprehensive overview of mite-associated bacteria and is a valuable reference database for future research on mites of agricultural, veterinary and/or medical importance.
Asunto(s)
Bacterias/aislamiento & purificación , Ácaros/microbiología , Animales , Bacterias/clasificación , Fenómenos Fisiológicos Bacterianos , SimbiosisRESUMEN
A new species of filarioid nematode of the genus Breinlia Yorke & Maplestone, 1926 (Nematoda: Filarioidea) is described from rodents in Lao PDR and according to its morphology, is placed in the subgenus Breinlia. Breinlia (Breinlia) jittapalapongi n. sp. occurs in the Asian house rat (Rattus tanezumi Temminck) and the Sikkim rat (Rattus andamanensis Blyth) and is reported from two localities (Luang Prabang and Champasak). The new species can be distinguished from all other congeners, which are mostly distributed in Australasia (twenty-two species), South East Asia (four species) and India (two species), by the following characters of the males: shape and size of gubernaculum, length of spicules, pattern of cloacal papillae and presence of sclerotised ring in the buccal capsule. This is the fifth species of Breinlia described from South East Asia.
Asunto(s)
Filarioidea/clasificación , Filarioidea/fisiología , Ratas/parasitología , Animales , Asia Sudoriental , Femenino , Filarioidea/ultraestructura , Masculino , Especificidad de la EspecieRESUMEN
Southeast Asia is a biodiversity hotspot that harbours many species of rodents, including some that live in close contact with humans. They host helminth parasites, some of which are of zoonotic importance. It is therefore important to understand the factors that influence the richness of the helminths parasitizing rodents. The specific objectives of this study were to evaluate rodent species as a factor determining helminth richness in rodent assemblages, to identify the major rodent helminth reservoir species and to explore the influence of habitat on helminth richness. We estimated helminth species richness using a large dataset of 18 rodent species (1,651 individuals) originating from Southeast Asia and screened for helminth parasites. The use of an unbiased estimator shows that the helminth species richness varies substantially among rodent species and across habitats. We confirmed this pattern by investigating the number of helminth species per individual rodent in all rodent species, and specifically in the two mitochondrial lineages Rattus tanezumi and R. tanezumi R3, which were captured in all habitats.
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Biodiversidad , Reservorios de Enfermedades/clasificación , Helmintiasis Animal/parasitología , Helmintos/clasificación , Enfermedades de los Roedores/parasitología , Animales , Asia Sudoriental/epidemiología , Ecosistema , Femenino , Geografía , Helmintiasis Animal/epidemiología , Helmintos/aislamiento & purificación , Humanos , Masculino , Prevalencia , Enfermedades de los Roedores/epidemiología , Roedores/clasificación , Zoonosis/parasitologíaRESUMEN
Ascaris lumbricoides, Trichuris trichiura, and Necator americanus are medically important soil-transmitted helminths (STHs) occurring frequently worldwide including Thailand. Fecal examination using a microscope has been recommended as the gold standard for diagnosis of STH infections, but suffers from low sensitivity. Recently, highly sensitive and specific assays, such as multiplex quantitative PCR, has been established, but the high cost and need for special instruments are still barriers limiting their applications in routine diagnosis. Therefore, a conventional multiplex PCR assay, with its lower cost and greater simplicity, was developed, for the simultaneous detection of STHs in fecal samples. The multiplex PCR assay was species-specific to the three STHs, and could detect one copy of DNA target. Compared with microscopic examination of fecal samples, sensitivity and specificity of the multiplex PCR was 87% and 83%, respectively. This multiplex PCR assay provides an alternative method for routine diagnosis of STHs infection, and might be applied for epidemiological studies of STHs in endemic areas.
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Ascariasis/diagnóstico , Reacción en Cadena de la Polimerasa Multiplex , Necatoriasis/diagnóstico , Suelo/parasitología , Tricuriasis/diagnóstico , Animales , Ascariasis/parasitología , Ascaris lumbricoides/aislamiento & purificación , Heces/parasitología , Humanos , Necator americanus/aislamiento & purificación , Necatoriasis/patología , Sensibilidad y Especificidad , Tailandia , Tricuriasis/parasitología , Trichuris/aislamiento & purificaciónRESUMEN
We collected fecal samples from 500 dogs and 300 cats from an animal refuge in Nakhon Nayok Province, Thailand to test for gastrointestinal protozoa and helminths using a formalin-ether concentration technique. The overall prevalence of parasites in stool from dogs was 36.2% (181/500), 35.7% (177/500) had helminths and 2.8% (14/500) had protozoa. The helminths were: hookworm (30.6%), Trichuris vulpis (16.0%), Toxocara canis (6.6%), Hymenolepis diminuta (1.2%), Spirometra mansoni (0.6%), and Dipylidium caninum (0.2%). Giardia duodenalis (2.8%) was found in the stool of dogs. The overall prevalence of parasites in stool from cats was 44.3% (133/300), 43.3% (130/300) were helminths and 6.0% (18/300) were protozoa. The helminths were hookworm (34.7%), T. cati (9.7%), S. mansoni (4.0%), Platynosomum fastosum (2.7%), Strongyloides sp (0.7%), and Echinostoma sp (0.3%). Two species of protozoa, Isospora sp (5.7%) and G. duodenalis (0.3%) were found in the stool of cats. Two percent of dogs and 5.0% of cats had mixed protozoan and helminthic infections. Dogs with double, triple, and quadruple helminthic infections were found at rates of 22.0%, 2.8%, and 0.2%, respectively. Cats with double and triple helminthic infections were found at rates of 9.7% and 1.0%, respectively. Quadruple helminthic infections were not found in cats, and double protozoan infections were not found in either dogs or cats.
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Enfermedades de los Gatos/parasitología , Gatos/parasitología , Enfermedades de los Perros/parasitología , Perros/parasitología , Enfermedades Gastrointestinales/parasitología , Enfermedades Gastrointestinales/veterinaria , Helmintiasis/parasitología , Infecciones por Protozoos/parasitología , Animales , Enfermedades de los Gatos/epidemiología , Enfermedades de los Perros/epidemiología , Heces/parasitología , Enfermedades Gastrointestinales/epidemiología , Helmintiasis/epidemiología , Prevalencia , Infecciones por Protozoos/epidemiología , Tailandia/epidemiologíaRESUMEN
BACKGROUND: The closely related Angiostrongylus cantonensis and Angiostrongylus malaysiensis have been reported to coexist in Thailand and share similar hosts and life cycles. Recently, in an angiostrongyliasis outbreak in Thailand, both A. cantonensis and A. malaysiensis were found in the cerebrospinal fluid of affected patients. Morphological similarities, overlapping distribution, shared hosts and habitats, and the close genetics of the two Angiostrongylus species can complicate accurate species identification. Addressing these challenges, this study aims to evaluate whether a correlation between the morphological and genetic identities of A. cantonensis and A. malaysiensis can improve species identification accuracy. METHODS: Angiostrongylus spp. specimens from five zoogeographical regions in Thailand were subjected to morphological and molecular identification using the mitochondrial cytochrome b gene and the nuclear internal transcribed spacer 2 region (ITS2). The morphological characters for males and females were then validated using the species identity obtained from the nuclear ITS2 region. RESULTS: The results revealed that morphological misidentifications between these two closely related species are common due to overlapping morphological characters. Although certain male traits such as body length and width aided species differentiation, female traits were found to be less reliable. Furthermore, hybrid forms (8.2%) were revealed through the ITS2 results, which can further complicate morphological identification. Mito-nuclear discordance was also present in 1.9% of the Angiostrongylus specimens from Thailand, suggesting a complex historical interbreeding between the species. CONCLUSIONS: Based on our findings, we suggest that nuclear ITS2 is a reliable marker for species identification of A. cantonensis and A. malaysiensis, especially in regions where both species coexist. Additionally, the scope and consequences of hybridization between the two closely related Angiostrongylus species should be further investigated in Thailand.
Asunto(s)
Angiostrongylus cantonensis , Angiostrongylus , Infecciones por Strongylida , Humanos , Animales , Masculino , Femenino , Angiostrongylus/genética , Angiostrongylus cantonensis/genética , Filogenia , Fenotipo , Infecciones por Strongylida/epidemiologíaRESUMEN
Cysticercus fasciolaris (C. fasciolaris) is the larval stage of a cestode parasite named Taenia taeniaeformis (T. taeniaeformis). C. fasiolaris is found in small rodents, especially rats. Rattus species are listed as intermediate hosts of this parasite, and cats are the main definitive host of C. fasiolaris. The objective of this study was to study the pathological, microscopic, and molecular aspects of C. fasciolaris in rodents residing in human residence areas. One hundred and two rodents were trapped in human settlements and dissected for larva-containing cyst examinations in the body cavity. The larvae of C. fasciolaris were investigated using histopathological examination, microscopic observations under a stereomicroscope and scanning electron microscope, and molecular detection using polymerase chain reaction. The prevalence of hepatic cysts containing larvae was 8.91% (95% CI = 4.16-16.24). In addition, the older larvae also had longer micropapillae. Histopathological investigation revealed normal hepatic tissue containing larvae and a scanty fluid cyst. The cyst capsule contains mostly mononuclear cells and spindle cells in all infected rats. The molecular detection using two primer sets revealed the amplicons were similar to the clade of C. fasciolaris. In the future, more investigation is necessary to fully understand the parasite's molecular pathogenesis and virulent molecules, which are less obvious.
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Quistes , Taenia , Ratas , Humanos , Animales , Cysticercus , Tailandia/epidemiología , Taenia/genética , Roedores , Larva , Quistes/veterinariaRESUMEN
Dogs play an important role as hosts and reservoirs for many zoonotic diseases. Ehrlichiosis, babesiosis and hepatozoonosis are a group of canine vector-borne diseases that can be transmitted via ectoparasites from dog to dog and also from dog to humans. This study focused on three main blood parasites of dog (i.e., Babesia spp., Ehrlichia spp. and Hepatozoon spp.) among two different landscape types of eight villages of Santhong Sub-district, Nan Province, Thailand. In this study, 149 dogs were surveyed and blood samples were collected. Blood parasite infections in dogs were assessed using molecular detection approach. Babesia canis vogeli, Babesia gibsoni, Ehrlichia canis and Hepatozoon canis were detected with prevalence of infection at 10.7%, 8.1%, 3.4% and 0.7%, respectively. In terms of landscape type, prevalence of overall blood parasites, particularly Babesia spp. infections were higher in dogs living in upland forested areas (28.3%) compared to dogs from lowland agricultural areas (12.3%). Data obtained from the questionnaires on perceptions of dog owners showed that dogs raised all the time outside owner's house, and those dogs whose owners have never bathed and cleaned were more likely to be exposed to blood parasites. As infected dogs could play an important role as reservoirs of the blood parasites, attitude of dog owners may affect public health in terms of zoonotic disease transmission. Effective control measures and surveillance program of arthropod vectors and blood parasite infection in dogs still need to be advocated to minimize zoonotic disease transmission.
Asunto(s)
Babesia , Babesiosis , Enfermedades de los Perros , Animales , Perros , Tailandia/epidemiología , Enfermedades de los Perros/epidemiología , Enfermedades de los Perros/parasitología , Babesiosis/epidemiología , Babesiosis/parasitología , Femenino , Masculino , Prevalencia , Babesia/aislamiento & purificación , Humanos , Ehrlichiosis/veterinaria , Ehrlichiosis/epidemiología , Zoonosis/parasitología , Coccidiosis/veterinaria , Coccidiosis/epidemiología , Coccidiosis/parasitología , Eucoccidiida/aislamiento & purificación , Ehrlichia canis/aislamiento & purificaciónRESUMEN
The present study aims at clarifying the poorly known phylogenetic relationships and systematics of cestodes of the family Davaineidae Braun, 1900 (Cyclophyllidea), primarily the genus Raillietina Fuhrmann, 1920 and of the subfamily Inermicapsiferinae (Anoplocephalidae) from mammals (mostly rodents, 31 new isolates) and birds (eight new isolates). Phylogenetic analyses are based on sequences of the large subunit ribosomal RNA gene (28S) and mitochondrial NADH dehydrogenase subunit 1 gene (nad1). The main phylogenetic pattern emerging from the present analysis is the presence of three independent lineages within the main clade of the subfamily Davaineinae, one of which is almost entirely confined to species from rodents and the other two show a mixture of species from birds and mammals. It is suggested that the major diversification of the main clade took place in birds, possibly in galliforms. The subsequent diversification included repeated host shifts from birds to mammals and to other birds, and from rodents to other mammals, showing that colonisation of new host lineages has been the main driver in the diversification of davaineine cestodes. It is also shown that all isolates of Inermicapsifer Janicki, 1910, mainly from rodents, form a monophyletic group positioned among Raillietina spp. in the "rodent lineage", indicating that the genus Inermicapsifer is a member of the family Davaineidae. This means that the subfamily Inermicapsiferinae and the family Inermicapsiferidae should be treated as synonyms of the Davaineidae, specifically the subfamily Davaineinae. Three additional genera generally included in the Inermicapsiferinae, i.e. Metacapsifer Spasskii, 1951, Pericapsifer Spasskii, 1951 and Thysanotaenia Beddard, 1911, are also assigned here to the Davaineidae (subfamily Davaineinae). Raillietina spp. were present in all three main lineages and appeared as multiple independent sublineages from bird and mammalian hosts, verifying the non-monophyly of the genus Raillietina and suggesting a presence of multiple new species and genera.
Asunto(s)
Cestodos , Infecciones por Cestodos , Filogenia , Roedores , Animales , Cestodos/clasificación , Cestodos/genética , Roedores/parasitología , Infecciones por Cestodos/veterinaria , Infecciones por Cestodos/parasitología , Aves , ARN Ribosómico 28S/genética , ARN Ribosómico 28S/análisis , NADH Deshidrogenasa/genéticaRESUMEN
Ascoschoengastia indica is one of the dominant chigger species in Southeast Asia and a potential carrier of scrub typhus, due in part to its cosmopolitan nature. This study explored the possible biological significance of the observed dimorphism in the shape of its scutum sensilla. Sensilla are specialized structures that are generally adapted to perform specific functions related to sensory capabilities, so their shape and sizes are expected to vary between taxa. We describe morphological variation of the sensilla of A. indica in Thailand. The sensilla had either a round or an ovoid, club-shaped form, which was not dependent on the particularly locality or host. Ignoring the precise function of the sensilla and their morphological variation, our study attempted to answer the following single question: Do the distinct forms of the sensilla indicate possible heterogeneity of the A. indica species? The two forms, named S1 and S2, were compared by genetic and morphometric techniques. The genetic analysis was based on the COI sequences, while the morphometric comparison used the scutum, an organ shown to be of taxonomic value for chigger mites. Neither morphometric nor genetic data revealed any evidence of a speciation process underlying the morphological variation in sensillum types.