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1.
Parasitol Res ; 119(3): 947-956, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31950252

RESUMO

Nowadays, snakes established as domestic exotic pets, harboring numerous (zoonotic) gastrointestinal parasites. In this parasitological survey, we used direct saline fecal smears (DSFS) to examine 586 stool samples from 71 different snake species either kept as pets in households or in zoological gardens in Germany. In addition to DSFS, carbol-fuchsin-fecal smears (n = 296), coproantigen ELISA tests (n = 98), and immunofluorescence assays (IFA; n = 77) for the detection reptile Cryptosporidium infections were conducted. Complete dissections of deceased snakes (n = 63) were also performed in order to gain data on endoparasite species burdens affecting domestic snakes. Overall, examined fecal samples contained 20 different parasite taxa: Ancylostomatid Kalicephalus spp. were the most prevalent nematode species (3.3%), followed by Strongyloides/Rhabdias (2.6%), flagellated protozoan trophozoites (e. g., Proteromonadida, Reteromonadida) (2.3%), Monocercomonas spp. (1.9%), Entamoeba spp. (1.4%), unsporulated coccidian oocysts (1.4%), Kapsulotaenia spp. (0.9%), Capillaria spp. (0.7%), indet. trematodes (0.5%), pentastomids (0.5%), spirurids (0.4%), Eimeria spp. (0.4%), ascarids (0.4%), Blastocystis sp. (0.2%), heterakids (0.2%), cestodes (Proteocephalidae) (0.2%), Plagiorchis spp. (0.2%), Cryptosporidium spp. (0.2%), Caryospora epicratesi (0.2%), and Sarcocystis spp. (0.2%). For Cryptosporidium, four carbol-fuchsin-stained smears (1.4%), 12 (12.2%) coproantigen ELISA-examined samples and 5.2% of examined samples were diagnosed with IFA. Fourteen (22.2%) of dissected snakes showed infections with various pathogenic nematode genera and 8 of them (12.7%) died due to protozoan parasitic infections. High prevalences of intestinal protozoan parasites resulting in severe pathological findings observed in dissected snakes call for more detailed investigations on gastrointestinal parasites.


Assuntos
Criptosporidiose/parasitologia , Enteropatias Parasitárias/parasitologia , Serpentes/parasitologia , Strongyloides/classificação , Strongyloides/isolamento & purificação , Estrongiloidíase/veterinária , Animais , Cryptosporidium/isolamento & purificação , Entamoeba/isolamento & purificação , Fezes/parasitologia , Jardins , Alemanha/epidemiologia , Oocistos/isolamento & purificação , Rhabdiasoidea/classificação , Rhabdiasoidea/isolamento & purificação
2.
Parasitology ; 146(7): 928-936, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30859923

RESUMO

Pathogens are increasingly implicated in amphibian declines but less is known about parasites and the role they play. We focused on a genus of nematodes (Rhabdias) that is widespread in amphibians and examined their genetic diversity, abundance (prevalence and intensity), and impact in a common toad (Rhinella horribilis) in Panama. Our molecular data show that toads were infected by at least four lineages of Rhabdias, most likely Rhabdias pseudosphaerocephala, and multiple lineages were present in the same geographic locality, the same host and even the same lung. Mean prevalence of infection per site was 63% and mean intensity of infection was 31 worms. There was a significant effect of host size on infection status in the wild: larger toads were more likely to be infected than were smaller conspecifics. Our experimental infections showed that toadlets that were penetrated by many infective Rhabdias larvae grew less than those who were penetrated by few larvae. Exposure to Rhabdias reduced toadlet locomotor performance (both sustained speed and endurance) but did not influence toadlet survival. The effects of Rhabdias infection on their host appear to be primarily sublethal, however, dose-dependent reduction in growth and an overall impaired locomotor performance still represents a significant reduction in host fitness.


Assuntos
Bufo bufo/parasitologia , Pulmão/parasitologia , Rhabdiasoidea/genética , Animais , Bufo bufo/crescimento & desenvolvimento , Feminino , Variação Genética , Locomoção , Pulmão/patologia , Masculino , Panamá , Contagem de Ovos de Parasitas , Prevalência , Rhabdiasoidea/patogenicidade
3.
Parasitol Int ; 67(6): 829-837, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29753096

RESUMO

A new species of the genus Serpentirhabdias Tkach, Kuzmin et Snyder, 2014, S. moi n. sp., is described from a colubroid snake Chironius exoletus from Caxiuanã National Forest, State of Pará, Brazil. The species is characterised by having a triangular oral opening, absence of the buccal capsule, presence of six minute onchia in the oesophastome, and excretory glands of approximately the same length as the oesophagus. These qualitative morphological characters, as well as some measurements, differentiate the new species from other Neotropical and Nearctic Serpentirhabdias spp. The morphological description of parasitic adults of S. moi n. sp. is complemented by the description of free-living stages including males, females, and infective larvae. Comparative analysis of partial sequences of cox1 and 12S mitochondrial genes strongly supported the status of S. moi n. sp. as a new species. Molecular phylogeny based on sequences of the nuclear DNA region spanning the 3' end of the 18S nuclear rRNA gene, ITS region (ITS1 + 5.8S + ITS2) and 5' end of the 28S gene supported monophyly of all rhabdiasid genera included in the analysis and placed the new species into the Serpentirhabdias clade as sister taxon to S. fuscovenosa.


Assuntos
Colubridae , Interações Hospedeiro-Parasita , Rhabdiasoidea/fisiologia , Infecções por Rhabditida/veterinária , Animais , Brasil/epidemiologia , DNA Espaçador Ribossômico/análise , Feminino , Larva/crescimento & desenvolvimento , Larva/fisiologia , Traços de História de Vida , Masculino , Filogenia , RNA Ribossômico 18S/análise , RNA Ribossômico 28S/análise , Rhabdiasoidea/genética , Rhabdiasoidea/crescimento & desenvolvimento , Infecções por Rhabditida/epidemiologia , Infecções por Rhabditida/parasitologia , Análise de Sequência de DNA
4.
Parasitology ; 144(14): 1956-1963, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28805166

RESUMO

In laboratory experiments, we investigated how media with varying ratio of peat:sand and two levels of compaction influence dispersal success of entomopathogenic nematode (EPN) species with different foraging strategies: Steinernema carpocapsae (ambusher), Heterorhabditis downesi (cruiser) and Steinernema feltiae (intermediate). Success was measured by the numbers of nematodes moving through a 4 cm column and invading a wax moth larva. We found that both compaction and increasing peat content generally decreased EPN infective juvenile (IJ) success for all three species. Of the three species, H. downesi was the least affected by peat content, and S. carpocapsae was the most adversely influenced by compaction. In addition, sex ratios of the invading IJs of the two Steinernema species were differentially influenced by peat content, and in the case of S. feltiae, sex ratio was also affected by compaction. This indicates that dispersal of male and female IJs is differentially affected by soil parameters and that this differentiation is species-specific. In conclusion, our study shows that organic matter: sand ratio and soil compaction have a marked influence on EPN foraging behaviour with implications for harnessing them as biological pest control agents.


Assuntos
Interações Hospedeiro-Parasita , Mariposas/parasitologia , Rhabdiasoidea/fisiologia , Solo/química , Strongyloidea/fisiologia , Animais , Larva/crescimento & desenvolvimento , Larva/parasitologia , Mariposas/crescimento & desenvolvimento , Razão de Masculinidade , Especificidade da Espécie
5.
Parasitol Int ; 66(5): 567-572, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28501634

RESUMO

During August 2010, a total of 66 cane toad Rhinella marina were collected in Laguna de Coyuca, Guerrero, Mexico and examined for the presence of helminths. Ninety-two percent were parasitized by 1 or more parasite species. A total of 4624 individuals were found, belonging to 8 helminth taxa (1 digenean, 1 cestode and 6 nematodes). Infracommunities harbored by this host species are highly variable (mean Jaccard similarity index 0.31±0.27); mean percent similarity index 0.26±0.32) and depauperate (mean richness 1.91±0.92; mean abundance 64.4±100.34); almost 50% of them were dominated by Rhabdias fuelleborni, a skin-penetrating nematode. Differences related to host gender and size were found, since males registered infracommunities with lower species richness and diversity than females. The reproductive condition of females (collected during the breeding season) might explain the results obtained; during this season, females invest less in resistance to infection in favor of investing resources in reproduction. However, confirmation of this statement can only be made by sampling in the dry season, when the toads do not reach their reproductive peak.


Assuntos
Bufo marinus/parasitologia , Helmintíase Animal/parasitologia , Helmintos/isolamento & purificação , Helmintos/fisiologia , Animais , Biodiversidade , Meio Ambiente , Feminino , Helmintíase Animal/epidemiologia , Helmintos/classificação , Especificidade de Hospedeiro , Masculino , México/epidemiologia , Reprodução , Rhabdiasoidea/isolamento & purificação , Rhabdiasoidea/fisiologia , Estações do Ano , Pele/parasitologia
6.
Dongwuxue Yanjiu ; 36(3): 119-32, 2015 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-26018855

RESUMO

Mass aggregations and migrations of millipedes despite numerous attempts to find causes for their occurrences are still an enigma. They have been reported from both southern and northern hemisphere countries, from highlands and lowlands of both tropical and temperate regions and they can involve species belonging to the orders Julida and Spirobolida, Polydesmida and Glomerida. According to the main suggestions put forward in the past, mass occurrences in Diplopoda occur: (1) because of a lack of food and a population increase beyond sustainable levels; (2) for the purpose of reproduction and in order to locate suitable oviposition sites; (3) to find overwintering or aestivation sites; (4) because of habitat disruption and changes in the local environment; (5) as a consequence of weather conditions the year (or winter and spring) before. A recent outbreak (November 2014) of a mass migration of the polydesmid Chamberlinius hualienensis Wang 1956 on the Japanese Izu Island of Hachijojima 300 km to the south of Tokyo gave this author an opportunity to review the existing literature on millipede mass migrations and to carry out additional observations on the phenomenon in the field as well as the laboratory. Hitherto unreported heavy infestations with phoretic deutonymphs of the mite Histiostoma sp. as well as dense populations of internal rhabditid nematodes (Oscheius cf. necromena and an unidentified species of the genus Fictor), suggest that infestations of this kind could be necromenic and either have been a contributing factor for the mass migration or been a consequence of so many individuals occurring together at close proximity. It is concluded that mass migrations and aggregations in millipedes do not have one common cause, but represent phenomena that often are seasonally recurring events and appear identical in their outcome, but which have evolved as responses to different causes in different millipede taxa and therefore need to be examined on a case-to-case basis.


Assuntos
Migração Animal , Artrópodes/fisiologia , Animais , Artrópodes/parasitologia , Ecossistema , Feminino , Ilhas , Japão , Masculino , Filogenia , Rhabdiasoidea/isolamento & purificação , Rhabdiasoidea/fisiologia , Estações do Ano
7.
J Comp Pathol ; 152(2-3): 260-4, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25670672

RESUMO

Subspectacular nematodiasis was diagnosed in three captive-bred juvenile ball pythons (Python regius) from two unrelated facilities within a 6-month period. The snakes were presented with similar lesions, including swelling of facial, periocular and oral tissues. Bilaterally, the subspectacular spaces were distended and filled with an opaque fluid, which contained nematodes and eggs. Histopathology showed nematodes throughout the periocular tissue, subspectacular space and subcutaneous tissue of the head. The nematodes from both facilities were morphologically indistinguishable and most closely resembled Serpentirhabdias species. Morphological characterization and genetic sequencing indicate this is a previously undescribed rhabdiasid nematode.


Assuntos
Boidae/parasitologia , Rhabdiasoidea/genética , Infecções por Rhabditida/veterinária , Animais , Infecções por Rhabditida/patologia
8.
Parasite ; 17(2): 91-105, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20597435

RESUMO

Rhabdias casiraghii n. sp. and R. kibiraensis n. sp. are described from Trioceros ellioti from Burundi and co-infection was observed in one of the host specimens. Distinctive characters between these species are, among others, the mouth and buccal capsule in front view, both of which are round in the former and laterally flattened in the latter species. Both species have a complete set of submedian head papillae (three in each submedian axis) as observed in the fourth stage larva of R. americanus from anurans. This primitive character opposes them to other species parasitic in Chamaeleonidae that have a single papilla per axis. The third species is the first described from the primitive chamaeleonid genus Brookesia; R. brygooi n. sp. from B. superciliaris from Madagascar can be distinguished from other Rhabdias in Chamaeleonidae by the small diameter of its mouth and buccal capsule. In this character, it resembles parasites from anurans. However, its infective larva has a rounded caudal extremity ornated with buds, as described in species of Rhabdias parasitic in Chamaeleonidae.


Assuntos
Rhabdiasoidea/anatomia & histologia , Rhabdiasoidea/isolamento & purificação , Animais , Burundi , DNA de Helmintos/genética , DNA de Helmintos/isolamento & purificação , Feminino , Madagáscar , Oviductos/anatomia & histologia , Rhabdiasoidea/classificação , Especificidade da Espécie , Útero/anatomia & histologia
9.
Parasitol Int ; 58(4): 375-83, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19646549

RESUMO

Rhabdias rhampholeonis n. sp. from Rhampholeon (Rh.) spectrum, Cameroon, and Rhabdias mariauxi n. sp. from Rieppeleon brevicaudatus, Tanzania, are the first lung worms from leaf chameleons. The new species are similar to the majority of species parasitic in chamaeleonids by having a long (>or=10 mm) and thick body (>or=500 microm), long oesophagus (>or=800 microm), wide buccal capsule (>or=40 microm) and low buccal ratio (<0.5). They most closely resemble Rhabdias chamaeleonis and Rhabdias cristati parasitic in Trioceros spp. from East Africa and Cameroon, respectively. Main distinctive characters are a buccal capsule composed of two segments and the head shape. The dorso-ventrally flattened buccal capsule of R. mariauxi n. sp. is unique in Rhabdias parasitising Chamaeleonidae. Sequences of the 12S rDNA and mitochondrial cytochrome c oxidase subunit 1 (coxI) genes were obtained and compared to those of Rhabdias okuensis, the only sequences published for chamaeleonid lung worms. The smallest nucleotide interspecific distances were found between R. mariauxi n. sp. and the former species of Trioceros from Cameroon. Hermaphroditism in females in the lungs, and R. mariauxi n. sp. free-living stages are like in other species from Chamaeleonidae, but the number of infective larvae produced per free-living female (one or two) was not fixed.


Assuntos
Lagartos/parasitologia , Rhabdiasoidea , Infecções por Rhabditida/veterinária , Animais , Ciclo-Oxigenase 1/genética , DNA de Helmintos/análise , Feminino , Masculino , Mitocôndrias/enzimologia , Dados de Sequência Molecular , Folhas de Planta , RNA Ribossômico/genética , Rhabdiasoidea/anatomia & histologia , Rhabdiasoidea/classificação , Rhabdiasoidea/genética , Rhabdiasoidea/crescimento & desenvolvimento , Infecções por Rhabditida/parasitologia , Análise de Sequência de DNA , Especificidade da Espécie
10.
Parasite ; 16(2): 111-23, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19585889

RESUMO

To date Rhabdias gemellipara is the only species described from Malagasy chameleons, but heterogeneity of the material had been suspected. 11 samples of Rhabdias parasites present in the Paris Natural History Museum collection were examined. The size and shape of the buccal capsule, shape and length of the oesophagus, shape of the apical region of the intestine, extent of the genital tract and structure of the cuticular vesicle led to the distinction of five species. Rhabdias rabetafikae n. sp. parasitises Columma cucullatum in the northeastern region (Cap Machoual). In the eastern region, R. nasutum n. sp. is parasitic in C. nasutum, and R. brevicorne n. sp. in C. brevicorne. All three species are similar in size to the African species parasitic in chameleons from which they can be distinguished by several characters. The small species, R. gemellipara, type host C. parsonii from the eastern region, was also found in C. brevicorne from the same geographic region. In the central region, Rhabdias sp., equally collected from C. brevicorne, is distinguished from R. gemellipara by a laterally flattened buccal capsule. All Malagasy species are hermaphrodites. Throughout the worm's life spermatozoids are formed intermittently in a band of cells situated at 1-2 mm from the extremity of the ovaries; they migrate in the ovaries and accumulate in the oviducts.


Assuntos
Lagartos/parasitologia , Rhabdiasoidea/classificação , Infecções por Rhabditida/veterinária , Animais , Feminino , Pulmão/parasitologia , Madagáscar , Masculino , Museus , Paris , Rhabdiasoidea/anatomia & histologia , Infecções por Rhabditida/parasitologia
11.
J Parasitol ; 95(2): 275-80, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18712948

RESUMO

We examined a population of northern leopard frogs to determine whether sex biases in investment in immunity, previously reported for this host species under controlled exposures to lung nematodes, is predictive of patterns of parasitism in nature. We examined Rhabdias ranae and Haematoloechus spp. infections in 74 breeding adult, 28 non-breeding adult, and 53 juvenile frogs. Contrary to our predictions, R. ranae prevalence and mean abundance were higher in breeding female frogs (prevalence: 39.4%, abundance: 3.05 +/- 0.85) than on breeding males (prevalence: 26.0%, abundance: 1.17 +/- 0.52), although no sex bias was observed among non-breeding adults or juvenile frogs. Female frogs also carried larger R. ranae worms, on average, than did males (females: 6407.38 microm +/- 153.80; males: 5198 microm +/- 131.09), regardless of age or breeding condition. We observed no sex-linked patterns of parasitism by Haematoloechus spp. worms in either adult or juvenile frogs. Alternative hypotheses, such as differences among sexes in the selection of thermal clines for hibernation, may explain the observed female bias in parasitism by nematode lungworms in nature and, thus, need to be considered.


Assuntos
Pneumopatias Parasitárias/veterinária , Rana pipiens/parasitologia , Rhabdiasoidea/fisiologia , Infecções por Rhabditida/veterinária , Trematódeos/fisiologia , Infecções por Trematódeos/veterinária , Fatores Etários , Análise de Variância , Animais , Cruzamento , Feminino , Interações Hospedeiro-Parasita , Pulmão/parasitologia , Pneumopatias Parasitárias/epidemiologia , Pneumopatias Parasitárias/parasitologia , Masculino , Ontário/epidemiologia , Prevalência , Rhabdiasoidea/anatomia & histologia , Infecções por Rhabditida/epidemiologia , Infecções por Rhabditida/parasitologia , Estações do Ano , Fatores Sexuais , Trematódeos/anatomia & histologia , Infecções por Trematódeos/epidemiologia , Infecções por Trematódeos/parasitologia
12.
Int J Parasitol ; 38(14): 1729-36, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18572173

RESUMO

Genetic studies have indicated that some parasite species formerly thought to be generalists are complexes of morphologically similar species, each appearing to specialize on different host species. Studies on such species are needed to obtain ecological and parasitological data to address whether there are fitness costs in parasitizing atypical host species. We examined whether lungworms from two anuran host species, Lithobates sylvaticus and Lithobates pipiens, differed in measures of infection success in L. pipiens recipient hosts. We also determined if the worms from the two host species were sources of genetically resolvable species of morphologically similar nematodes. Sequences of internal transcribed spacer and lsrDNA regions of adult lungworms from each host species indicated that worms from L. sylvaticus matched Rhabdias bakeri, whereas worms from L. pipiens matched Rhabdias ranae. Our work suggested that these morphologically similar species are distant non-sibling taxa. We infected male and female metamorphs experimentally with lungworm larvae of the two species. We observed higher penetration, higher prevalence and higher mean abundance of adult worms in lungs of male and female metamorphs exposed to R. ranae larvae than in lungs of metamorphs exposed to R. bakeri larvae. Furthermore, metamorphs exposed to R. ranae larvae carried larger adult female worms in their lungs. Some variation in infection measures depended on host sex, but only for one parasite species considered. Overall, the differential establishment and reproductive potential of R. ranae and R. bakeri in L. pipiens suggests co-adaptation.


Assuntos
Anuros/parasitologia , Rhabdiasoidea/patogenicidade , Infecções por Rhabditida/parasitologia , Animais , DNA Intergênico , Análise Multivariada , Reação em Cadeia da Polimerase , Rhabdiasoidea/classificação , Rhabdiasoidea/genética , Infecções por Rhabditida/veterinária
13.
Parasitology ; 135(Pt 1): 95-104, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17908359

RESUMO

In hybridogenetic systems, hybrid individuals are fully heterozygous because one of the parental genomes is discarded from the germinal line before meiosis. Such systems offer the opportunity to investigate the influence of heterozygosity on susceptibility to parasites. We studied the intensity of lung parasites (the roundworm Rhabdias bufomis and the fluke Haplometra cylindracea) in 3 populations of water frogs of the Rana lessonae-esculenta complex in eastern France. In these mixed populations, hybrid frogs (R. esculenta) outnumbered parental ones (R. lessonae). Despite variation in parasite intensity and demographic variability among populations, the relationship between host age and intensity of parasitism suggests a higher susceptibility in parentals than in hybrids. Mortality is probably enhanced by lung parasites in parental frogs. On the other hand, while parental frogs harboured higher numbers of H. cylindracea than hybrid frogs, the latter had higher numbers of R. bufonis. Despite such discrepancies, these results support the hybrid resistance hypothesis, although other factors, such as differences in body size, age-related immunity, differential exposure risks and hemiclonal selection, could also contribute to the observed patterns of infection.


Assuntos
Heterozigoto , Doenças Parasitárias em Animais/genética , Ranidae , Infecções por Rhabditida/veterinária , Infecções por Trematódeos/veterinária , Fatores Etários , Animais , Constituição Corporal , Quimera/genética , Quimera/parasitologia , Feminino , França/epidemiologia , Genótipo , Imunidade Inata/genética , Pulmão/parasitologia , Masculino , Doenças Parasitárias em Animais/mortalidade , Doenças Parasitárias em Animais/parasitologia , Ranidae/genética , Ranidae/parasitologia , Rhabdiasoidea/isolamento & purificação , Rhabdiasoidea/patogenicidade , Infecções por Rhabditida/genética , Infecções por Rhabditida/mortalidade , Infecções por Rhabditida/parasitologia , Trematódeos/isolamento & purificação , Trematódeos/patogenicidade , Infecções por Trematódeos/genética , Infecções por Trematódeos/mortalidade , Infecções por Trematódeos/parasitologia
14.
Parasite ; 15(4): 553-64, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19202762

RESUMO

The lung nematodes of the genus Rhabdias parasitic in chameleons were previously only known from east Africa and Madagascar. Two new species are described from Cameroon: i) Rhabdias okuensis n. sp., type-host Chamaeleo (Trioceros) quadricomis gracilior, from Mont Oku, is frequent; it resembles R. jarki from Burundi, with a short buccal capsule and a long, thin oesophagus, and is distinguished by its large cervical vesicle and cephalic characters (mouth aperture, papillae). The female parasites are hermaphroditic (spermatozoa identified) and they pierce the lung wall and induce lesions, as R. jarki. In the same locality, another chameleon, C. (T.) w. wiedersheimi also harbours R. okuensis, as demonstrated with the 12S rDNA and coxl gene sequences. ii) R. cristati n. sp., type-host C. (T.) cristatus, from Mount Cameroon, is described from one heavily infected specimen; it resembles R. chamaeleonis from East Africa, and is distinguished by the large buccal capsule and the thick apex of the intestine. The free-living phase, studied in R. okuensis, presents characters of other Rhabdias from chameleons: heterogony, development of larvae through matricidal endotoky, infective larval stages with a thick, rounded caudal extremity, exuvium transformed into a thick cuticular sheeth. Each free-living female produces one larva, as in other African Rhabdias, whereas the female of R. gemellipara, a parasite of a Malagasy chameleon, produces two larvae.


Assuntos
Lagartos/parasitologia , Pulmão/parasitologia , Rhabdiasoidea/anatomia & histologia , Rhabdiasoidea/classificação , Infecções por Rhabditida/veterinária , Animais , Camarões , Transtornos do Desenvolvimento Sexual , Feminino , Masculino , Filogenia , Rhabdiasoidea/isolamento & purificação , Infecções por Rhabditida/parasitologia
15.
J. venom. anim. toxins incl. trop. dis ; 13(1): 122-129, 2007. tab, ilus
Artigo em Inglês | LILACS | ID: lil-444616

RESUMO

The aim of the present study was to evaluate the frequency of rhabdiasid nematodes in recently captured Crotalus durissus terrificus snakes from São Paulo State, Brazil. Fifty snakes (34 males and 16 females) were studied and each one was evaluated for the presence of that nematode at the moment of receipt at the Institution and after 90 days of quarantine inside individual cages. Tracheopulmonary washeswere examined. Snakes that died during quarantine underwent necropsy and lung examination. Analysis of the results obtained at the two evaluation times (0 and 90 days), in addition to the data obtained during necropsies, showed that 44 percent (18 males and 4 females) of the C. d. terrificus snakes were naturally infected by rhabdiasid nematodes. These data demonstrate the parasitism level in natural conditions and are important for the sanitary handling of these reptiles in captivity.


Assuntos
Animais , Masculino , Feminino , Crotalus cascavella , Nematoides , Rhabdiasoidea
16.
Parasite ; 11(1): 15-31, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15071824

RESUMO

Lung-dwelling females of Rhabdias (Rhabdiasidae), and possible migrating ceolomic young females were searched for in 46 chameleons, belonging to seven species. Rhabdias chamaeleonis, the single species identified to date in Africa, was found in Chamaeleo (Trioceros) johnstoni and C. (T.) hoehnelii, and redescribed; the sizes of the buccal capsule and oesophagus were stable compared to the length of the female parasiles, which varied from 6 mm to 22 mm in length. A second species, R. jarki n. sp., was identified from one C. (T.) johnstoni; it differed from R. chamaeleonis in the shape of anterior region, the longer and slender oesophagus (ratio bulb diameter-body diameter at that level about 1/5 instead of 1/2), the arrangement of the head papillae, the shape of the buccal capsule, and the anatomy of the genital apparatus: one of the ovaries (the anterior or posterior one according to the specimen) had a band of small cells, among larger ovocytes of the synapsis zone, which were likely to generate the spermatozoa present in the oviducts, whereas these two elements were absent from R. chamaeleonis. The parasitic females of R. jarki thus appeared to be hermaphroditic, whereas those of R. chamaeleonis appeared to be parthenogenetic. The free living phase of these Rhabdias species was heterogonic. The infective larva of R. chamaeleonis was 360-590 microns long, unmolile and at third stage inside the maternal cuticle. The free-living male of R. jarki was described. The numerous infective larvae recovered from cultures of unidentified Rhabdias were all in maternal cuticle (one larva/female instead of two as in R. gemellipara from Calumma parsonii, from Madagascar) and two kinds of larvae were identified, R. chamaeleonis and larvae 700-900 microns long provisionally identified to R. jarki. The behaviour of infective larvae and a few successful infections of insects suggest that, in the field, insect transport hosts are involved in transmission and in preventing infective larvae from drying out.


Assuntos
Lagartos/parasitologia , Rhabdiasoidea/anatomia & histologia , Rhabdiasoidea/classificação , Infecções por Rhabditida/veterinária , Animais , Transtornos do Desenvolvimento Sexual , Feminino , Masculino , Filogenia , Infecções por Rhabditida/parasitologia
17.
Oecologia ; 135(3): 469-76, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12721838

RESUMO

We tested the hypothesis that exposure of leopard frogs ( Rana pipiens) to agricultural pesticides can affect the infection dynamics of a common parasite of ranid frogs, the lungworm Rhabdias ranae. After a 21-day exposure to sublethal concentrations of a pesticide mixture composed of atrazine, metribuzin, aldicarb, endosulfan, lindane and dieldrin, or to control solutions (water, dimethyl sulfoxide), parasite-free juvenile frogs were challenged with 30 infective larvae of R. ranae. Approximately 75% of the larvae penetrated the skin and survived in both exposed and control animals, suggesting that pesticides did not influence host recognition or penetration components of the transmission process. Rather, we found that the migration of R. ranae was significantly accelerated in hosts exposed to the highest concentrations of pesticides, leading to the establishment of twice as many adult worms in the lungs of frogs 21 days post-infection. Pesticide treatment did not influence the growth of lungworms but our results indicate that they matured and reproduced earlier in pesticide-exposed frogs compared to control animals. Such alterations in life history characteristics that enhance parasite transmission may lead to an increase in virulence. Supporting evidence shows that certain components of the frog immune response were significantly suppressed after exposure to the pesticide mixture. This suggests that the immune system of anurans exerts a control over lungworm migration and maturation and that agricultural contaminants can interfere with these control mechanisms. Our results also contribute to the ongoing debate regarding the role that anthropogenic factors could play in the perplexing disease-related die-offs of amphibians observed in several parts of the world.


Assuntos
Praguicidas/efeitos adversos , Rana pipiens/parasitologia , Rhabdiasoidea/patogenicidade , Poluentes Químicos da Água/efeitos adversos , Animais , Larva/crescimento & desenvolvimento , Larva/parasitologia , Reprodução , Rhabdiasoidea/crescimento & desenvolvimento , Análise de Sobrevida
18.
J Parasitol ; 89(1): 113-7, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12659312

RESUMO

Rhabdias anolis n. sp. from the lungs of Anolis frenatus collected in Panama is described and illustrated. Rhabdias anolis n. sp. represents the 45th species assigned to the genus and the ninth from the Notropical Realm. It is distinguished from all other Neotropical species by the presence of a pair of sessile lateral papillae on its tail.


Assuntos
Lagartos/parasitologia , Pneumopatias Parasitárias/veterinária , Rhabdiasoidea/classificação , Infecções por Rhabditida/veterinária , Animais , Feminino , Pulmão/parasitologia , Pneumopatias Parasitárias/epidemiologia , Pneumopatias Parasitárias/parasitologia , Panamá/epidemiologia , Rhabdiasoidea/anatomia & histologia , Rhabdiasoidea/isolamento & purificação , Infecções por Rhabditida/epidemiologia , Infecções por Rhabditida/parasitologia
19.
J Invertebr Pathol ; 71(3): 248-50, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9538029

RESUMO

The activity and natural mortality of Sitona lineatus weevils during the egg laying period may be connected with host plant preference. Preference of S. lineatus adults for early field pea and other pea cultivars influences their low feeding activity and results in lopff average body weight and higher susceptibility to entomogenous nematodes, Steinernema carpocapsae, S. feltiae, and Heterorhabditis bacteriophora.


Assuntos
Comportamento Apetitivo , Besouros/fisiologia , Besouros/parasitologia , Rhabdiasoidea , Animais , Fabaceae , Plantas Medicinais
20.
Parasitology ; 104 Pt 1: 179-87, 1992 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1614734

RESUMO

Density-dependence in worm establishment, numbers, biomass and larval production were examined in primary infections of 0, 10, 40, 80 and 160 larvae of the lung nematode, Rhabdias bufonis in the common toad, Bufo bufo. The infection procedure established 4 non-overlapping levels of infection which persisted until 6 weeks post-infection (p.i.), after which there was an overall decline up to 12 weeks p.i. Worm numbers had no direct effect on adult worm survival but temporal changes in worm weight were density-dependent. Adult worm establishment in the lungs declined significantly as the numbers of worms in the lungs increased. At the lowest exposure dose, 86% of the larvae administered reached maturity in the lungs while at the highest, only 37% did so. Also, the numbers of immature larvae outside the lungs increased as adult worm numbers increased. Both features provide evidence for a threshold limit to the numbers of worms maturing in the lungs. Worm numbers also affected larval output per host and per capita fecundity. A significant positive relationship between per capita fecundity and per capita worm weight suggested that density-dependence acted primarily to constrain the growth of individual worms. Finally, the constraints imposed on worm growth and fecundity were apparently relaxed when worm density decreased, providing evidence for density-dependent flexibility in per capita fecundity. Density-dependence in worm establishment and per capita fecundity are mechanisms which may potentially regulate this host-parasite interaction in the field. Both mechanisms may be functionally related to physical space limitations in the lungs, within which worms must compete for finite nutrients.


Assuntos
Bufo bufo/parasitologia , Rhabdiasoidea/crescimento & desenvolvimento , Estrongiloidíase/veterinária , Análise de Variância , Animais , Larva/crescimento & desenvolvimento , Dinâmica Populacional , Estrongiloidíase/parasitologia
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