RESUMO
The efficacy of afoxolaner was evaluated in two captive Burmese python snakes, which were naturally infested with Ophionyssus natricis mites. The administration of a single oral dose of afoxolaner eliminated live O. natricis mites from both snakes by Day 3. Environmental samples collected from the snakes' terrariums were negative for dead mites by Day 30.
L'efficacité de l'afoxolaner a été évaluée chez deux serpents python birmans captifs, naturellement infestés par des acariens Ophionyssus natricis. L'administration d'une dose orale unique d'afoxolaner a éliminé les acariens O. natricis vivants des deux serpents à jour 3. Les échantillons environnementaux prélevés dans les terrariums des serpents étaient négatifs pour les acariens morts à jour 30.
Se evaluó la eficacia de afoxolaner en dos serpientes pitón birmanas cautivas, que estaban naturalmente infestadas con ácaros Ophionyssus natricis. La administración de una sola dosis oral de afoxolaner eliminó los ácaros O. natricis vivos de ambas serpientes en el día 3. Las muestras ambientales recolectadas de los terrarios de las serpientes dieron negativo para ácaros muertos en el día 30.
A eficácia do afoxolaner foi avaliada em duas cobras python birmanesas de cativeiro, que foram naturalmente infestadas com ácaros Ophionyssus natricis. A administração de uma única dose oral de afoxolaner eliminou ácaros O. natricis vivos de ambas as cobras no dia 3. As amostras ambientais coletadas dos terrários das cobras foram negativas para ácaros mortos no dia 30.
Assuntos
Boidae , Isoxazóis , Infestações por Ácaros , Ácaros , Naftalenos , Animais , Boidae/parasitologia , Isoxazóis/uso terapêutico , Infestações por Ácaros/tratamento farmacológico , Infestações por Ácaros/veterinária , Naftalenos/uso terapêuticoRESUMO
Cryptosporidium is an important enteric pathogen that infects a wide range of humans and animals. Rapid and reliable detection and characterisation methods are essential for understanding the transmission dynamics of the parasite. Sanger sequencing, and high-throughput sequencing (HTS) on an Ion Torrent platform, were compared with each other for their sensitivity and accuracy in detecting and characterising 25 Cryptosporidium-positive human and animal faecal samples. Ion Torrent reads (n = 123,857) were obtained at both 18S rRNA and actin loci for 21 of the 25 samples. Of these, one isolate at the actin locus (Cattle 05) and three at the 18S rRNA locus (HTS 10, HTS 11 and HTS 12), suffered PCR drop-out (i.e. PCR failures) when using fusion-tagged PCR. Sanger sequences were obtained for both loci for 23 of the 25 samples and showed good agreement with Ion Torrent-based genotyping. Two samples both from pythons (SK 02 and SK 05) produced mixed 18S and actin chromatograms by Sanger sequencing but were clearly identified by Ion Torrent sequencing as C. muris. One isolate (SK 03) was typed as C. muris by Sanger sequencing but was identified as a mixed C. muris and C. tyzzeri infection by HTS. 18S rRNA Type B sequences were identified in 4/6 C. parvum isolates when deep sequenced but were undetected in Sanger sequencing. Sanger was cheaper than Ion Torrent when sequencing a small numbers of samples, but when larger numbers of samples are considered (n = 60), the costs were comparative. Fusion-tagged amplicon based approaches are a powerful way of approaching mixtures, the only draw-back being the loss of PCR efficiency on low-template samples when using primers coupled to MID tags and adaptors. Taken together these data show that HTS has excellent potential for revealing the "true" composition of species/types in a Cryptosporidium infection, but that HTS workflows need to be carefully developed to ensure sensitivity, accuracy and contamination are controlled.
Assuntos
Actinas/genética , Cryptosporidium/classificação , Técnicas de Genotipagem/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , RNA Ribossômico 18S/genética , Animais , Boidae/parasitologia , Bovinos , Custos e Análise de Custo , Cryptosporidium/genética , Cryptosporidium/isolamento & purificação , Fezes/parasitologia , Técnicas de Genotipagem/economia , Sequenciamento de Nucleotídeos em Larga Escala/economia , HumanosRESUMO
Sarcocystis spp. represent apicomplexan parasites. They usually have a heteroxenous life cycle. Around 200 species have been described, affecting a wide range of animals worldwide, including reptiles. In recent years, large numbers of reptiles have been imported into Europe as pets and, as a consequence, animal welfare and species protection issues emerged. A sample of pooled feces from four confiscated green pythons (Morelia viridis) containing Sarcocystis spp. sporocysts was investigated. These snakes were imported for the pet trade and declared as being captive-bred. Full length 18S rRNA genes were amplified, cloned into plasmids and sequenced. Two different Sarcocystis spp. sequences were identified and registered as Sarcocystis sp. from M. viridis in GenBank. Both showed a 95-97% sequence identity with the 18S rRNA gene of Sarcocystis singaporensis. Phylogenetic analysis positioned these sequences together with other Sarcocystis spp. from snakes and rodents as definitive and intermediate hosts (IH), respectively. Sequence data and also the results of clinical and parasitological examinations suggest that the snakes were definitive hosts for Sarcocystis spp. that circulate in wild IH. Thus, it seems unlikely that the infected snakes had been legally bred. Our research shows that information on the infection of snakes with Sarcocystis spp. may be used to assess compliance with regulations on the trade with wildlife species.
Assuntos
Boidae/parasitologia , Sarcocystis/isolamento & purificação , Sarcocistose/veterinária , Animais , Animais Selvagens , Sequência de Bases , Cruzamento/legislação & jurisprudência , Clonagem Molecular , DNA Ribossômico/química , DNA Ribossômico/genética , Fezes/parasitologia , Alemanha , Indonésia , Dados de Sequência Molecular , RNA Ribossômico 18S/genética , Sarcocystis/genética , Sarcocistose/parasitologia , Análise de Sequência de DNA/veterináriaRESUMO
Choleoeimeria ghaffari n. sp. is described from the gallbladder of Eryx jayakari Boulenger in Saudi Arabia. Oöcysts are tetrasporocystic, cylindroidal, 23 × 14 µm, with a smooth bi-layered wall and length/width ratio of 1.5, without micropyle, oöcyst residuum and polar granule. Sporocysts are subspheroidal to ellipsoidal, 8 × 6 µm, with length/width ratio of 1.4, without Stieda, sub-Stieda and para-Stieda bodies but with sporocyst residuum. Sporozoites are banana-shaped measuring 10 × 1.5 µm. The endogenous development was found to occur in the gallbladder epithelium and the extrahepatic bile ducts. Mature meronts are spheroidal, c.10 µm wide, and suspected to produce 12-16 merozoites. Microgamonts are irregular in shape, 13 × 10 µm, whereas macrogamonts are mostly subspheroidal, c.12 µm wide, with a prominent centrally-located nucleus. Based on oöcyst morphology and the site of endogenous development (epithelium of the gallbladder and bile ducts) the new eimeriid coccidian was placed in the genus Choleoeimeria Paperna & Landsberg, 1989.
Assuntos
Boidae/parasitologia , Eimeriidae/classificação , Eimeriidae/citologia , Animais , Vesícula Biliar/parasitologia , Arábia Saudita , Especificidade da EspécieRESUMO
Myiases are caused by the presence of maggots in vertebrate tissues and organs. Myiases have been studied widely in humans, farm animals, and pets, whereas reports of myiasis in reptiles are scarce. We describe a case of myiasis caused by the Megaselia scalaris (Loew) in an Indian python (Python molurus bivittatus, Kuhl) (Ophida: Boidae). The python, 15 yr old, born and reared in a terrarium in the mainland of Venice (Italy), was affected by diffuse, purulent pneumonia caused by Burkholderia cepacia. The severe infestation of maggots found in the lungs during an autopsy indicated at a myiasis.
Assuntos
Animais de Zoológico , Boidae/parasitologia , Burkholderia cepacia/isolamento & purificação , Dípteros/fisiologia , Miíase/veterinária , Pneumonia Bacteriana/veterinária , Animais , Boidae/microbiologia , Evolução Fatal , Feminino , Interações Hospedeiro-Parasita , Miíase/complicações , Miíase/parasitologia , Pneumonia Bacteriana/complicações , Pneumonia Bacteriana/microbiologiaRESUMO
We collected ectoparasites from 27 of 51 wild-caught, free-ranging exotic reptiles examined in Florida from 2003 to 2008. Sampled animals represented eight species, five of which yielded ectoparasites. Reported new parasite distribution records for the United States include the following: the first collection of the African tick Amblyomma latum (Koch) from a wild-caught animal [ball python, Python regius (Shaw)] in the United States; the first collection of the lizard scale mite Hirstiella stamii (Jack) from any wild-caught animal [green iguana, Iguana iguana (L.)]; and the first collection of the lizard scale mite Geckobia hemidactyli (Lawrence) in the continental United States from a wild-caught tropical house gecko, Hemidactylus mabouia (Moreau de Jonnès). We also report the first collections of the Neotropical ticks Amblyomma rotundatum (Koch) and Amblyomma dissimile (Koch) from wild-caught Burmese pythons, Python molurus bivittatus (Kuhl); the first collections of A. dissimile from a wild-caught African savannah monitor, Varanus exanthematicus (Bosc); and from wild-caught green iguanas in the United States; and the first collections of the native chiggers Eutrombicula splendens (Ewing) and Eutrombicula cinnabaris (Ewing) from wild-caught Burmese pythons. These reports may only suggest the diversity of reptile ectoparasites introduced and established in Florida and the new host-parasite relationships that have developed among exotic and native ectoparasites and established exotic reptiles.
Assuntos
Boidae/parasitologia , Iguanas/parasitologia , Espécies Introduzidas , Ácaros , Carrapatos , Animais , Feminino , Florida , MasculinoRESUMO
A new species of Caryospora Léger, 1904 (Apicomplexa: Eimeriidae), C. durelli n. sp., is described from the endangered Round Island boa Casarea dussumieri (Schlegel) (Serpentes: Bolyeridae) from Round Island, Mauritius. Six of 11 hosts were infected. Oöcysts are spherical to subspherical, 19.2 × 18.2 (17.5-21 × 16-21) µm, n = 20, and have a shape index (mean length/mean width) of 1.05 (1.02-1.09). The bi-layered wall is composed of an outer layer of c.0.6 µm thick and an inner layer of c.0.4 µm thick. A micropyle, oöcyst residuum and polar granule are absent. Sporocysts are ellipsoidal, 14.7 × 11.0 (13-16 × 9.5-11.5) µm, n = 20, and have a shape index of 1.33. Both Stieda and substieda bodies are present. The sporocyst residuum measures c.12 × 4.5 µm, is surrounded by sporozoites and composed of numerous granules. Refractile bodies are present but not clearly visible. This is the first coccidian parasite reported from the family Bolyeridae and the first species of Caryospora durrelli [corrected] reported from the Mascarenes. Conservation issues concerning parasites of endangered host species are discussed.
Assuntos
Boidae/parasitologia , Eimeriidae/classificação , Espécies em Perigo de Extinção , Animais , Eimeriidae/citologia , Eimeriidae/crescimento & desenvolvimento , Feminino , Masculino , Maurício , Oocistos/citologiaRESUMO
Ophidascaris species are parasitic roundworms that inhabit the python gut, resulting in severe granulomatous lesions or even death. However, the classification and nomenclature of these roundworms are still controversial. Our study aims to identify a snake roundworm from the Burmese python (Python molurus bivittatus) and analyze the mitochondrial genome. We identified this roundworm as Ophidascaris baylisi based on the morphology and cytochrome c oxidase subunit I (cox1) sequence. Ophidascaris baylisi complete mitochondrial genome was 14,784 bp in length, consisting of two non-coding regions and 36 mitochondrial genes (12 protein-coding genes, 22 tRNA genes, and two rRNA genes). The protein-coding genes used TTG, ATG, ATT, or TTA as start codons and TAG, TAA, or T as stop codons. All tRNA genes showed a TV-loop structure, except trnS1AGN and trnS2UCN revealed a D-loop structure. The mitochondrial large ribosomal subunit 16S (rrnL) and small ribosomal subunit 12S (rrnS) were 956 bp and 700 bp long, respectively. Phylogenetic analysis based on O. baylisi mitochondrial protein-coding genes demonstrated that O. baylisi clustered with the family Ascarididae members and was most closely related to Ophidascaris wangi. These results may enhance the nematode mitochondrial genome database and provide valuable molecular markers for further research on the taxonomy, phylogeny, and genetic relationships of Ophidascaris nematodes.
Assuntos
Ascaridoidea/genética , Boidae/parasitologia , Genoma Helmíntico , Genoma Mitocondrial , Animais , Infecções por Ascaridida/parasitologiaRESUMO
The pathogenic Entamoeba species in snakes is widely regarded to be Entamoeba invadens, which can cause severe amoebiasis with up to 100% mortality. In this case report, we describe a ball python (Python regius) that died after short-term weight loss. Necropsy revealed severe necrotizing colitis with large numbers of intralesional Entamoeba trophozoites. Molecular genetic analysis identified these trophozoites as Entamoeba ranarum, a parasite more usually found in amphibians. Furthermore, the extended history revealed that toads (Rhinella marina) had been housed together with the python. This report illustrates the danger of protozoal cross-infections in exotic animals as well as the importance of molecular genetic tools in Entamoeba diagnosis.
Assuntos
Boidae/parasitologia , Entamebíase/veterinária , AnimaisRESUMO
Invasive Burmese pythons (Python bivittatus Kuhl, 1820) have introduced a lung parasite, Raillietiella orientalis, (Hett, 1915) from the python's native range in Southeast Asia to its introduced range in Florida, where parasite spillover from pythons to two families and eight genera of native snakes has occurred. Because these novel host species present a diversity of ecological and morphological traits, and because these parasites attach to their hosts with hooks located on their cephalothorax, we predicted that R. orientalis would exhibit substantial, host-associated phenotypic plasticity in cephalothorax shape. Indeed, geometric morphometric analyses of 39 parasites from five host species revealed significant variation among host taxa in R. orientalis cephalothorax shape. We observed differences associated with host ecology, where parasites from semi-aquatic and aquatic snakes exhibited the greatest morphological similarity. Morphological analyses of R. orientalis recovered from invasive pythons, native pit vipers, and terrestrial snakes each revealed distinct shapes. Our results suggest R. orientalis can exhibit significant differences in morphology based upon host species infected, and this plasticity may facilitate infection with this non-native parasite in a wide array of novel squamate host species.
Assuntos
Boidae/parasitologia , Espécies Introduzidas , Doenças Parasitárias em Animais/parasitologia , Pentastomídeos/patogenicidade , Adaptação Fisiológica , Animais , Variação Biológica da População , Ecossistema , Florida , Especificidade de Hospedeiro , Interações Hospedeiro-Parasita , Pentastomídeos/genética , Pentastomídeos/fisiologia , Serpentes/parasitologiaRESUMO
A female boa (Boa constrictor) from a zoological collection was submitted for necropsy after sudden death. Prominent pathological findings included a diphtheroid colitis, endoparasitism, focal pneumonia and inclusion bodies typical for inclusion body disease (IBD). In the colon entamoebae were identified, which differed in size and distribution from Entamoeba invadens. Gene sequence analysis of the 18S ribosomal RNA revealed 100% similarity with an Entamoeba species from the African bullfrog (Pyxicephalus adspersus), probably Entamoeba ranarum. The snake was possibly immunosuppressed, and the source of infection remains unclear. This is the first report of an infection with an amphibian Entamoeba species associated with colitis in a snake.
Assuntos
Anfíbios/parasitologia , Boidae/parasitologia , Colite/veterinária , Entamoeba/classificação , Entamebíase/veterinária , Animais , Sequência de Bases , Colite/parasitologia , Colo/parasitologia , Colo/patologia , DNA de Protozoário/genética , Entamoeba/genética , Entamoeba/isolamento & purificação , Entamebíase/parasitologia , FemininoRESUMO
Two experimental trials were performed to elucidate the role of rodents in the life cycle of Hepatozoon species using snakes as intermediate hosts. In one trial, two ball pythons, Python regius Shaw, 1802 were force fed livers of laboratory mice previously inoculated with sporocysts of Hepatozoon ayorgbor Sloboda, Kamler, Bulantová, Votýpka et Modrý, 2007. Transmission was successful in these experimentally infected snakes as evidenced by the appearance of intraerythrocytic gamonts, which persisted until the end of trial, 12 months after inoculation. Developmental stages of haemogregarines were not observed in histological sections from mice. In another experimental trial, a presence of haemogregarine DNA in mice inoculated with H. ayorgbor was demonstrated by PCR in the liver, lungs and spleen.
Assuntos
Apicomplexa/isolamento & purificação , Boidae/parasitologia , Vetores de Doenças , Infecções Protozoárias em Animais/transmissão , Roedores/parasitologia , Animais , DNA de Protozoário/isolamento & purificação , Eritrócitos/parasitologia , Feminino , Fígado/parasitologia , Pulmão/parasitologia , Camundongos , Reação em Cadeia da Polimerase/métodos , Baço/parasitologiaRESUMO
In the present study, we report a case of hyperparasitism in Amblyomma rotundatum. During examination of live ticks immediately after collecting them from Boa constrictor snakes held in a reptile facility in Mossoró, RN, northeastern Brazil, 1 unengorged tick female was seen attached to the venter of a partially engorged female. The hypostome and chelicerae of the unengorged female had penetrated the integument of the partially engorged female to the level of the basis capitulli and the palps were splayed outward. To our knowledge, we present the second report of hyperparasitism for the genus Amblyomma.
Assuntos
Ixodidae/fisiologia , Animais , Boidae/parasitologia , Comportamento Alimentar , Feminino , MasculinoRESUMO
Hepatozoon ayorgbor n. sp. is described from specimens of Python regius imported from Ghana. Gametocytes were found in the peripheral blood of 43 of 55 snakes examined. Localization of gametocytes was mainly inside the erythrocytes; free gametocytes were found in 15 (34.9%) positive specimens. Infections of laboratory-reared Culex quinquefasciatus feeding on infected snakes, as well as experimental infection of juvenile Python regius by ingestion of infected mosquitoes, were performed to complete the life cycle. Similarly, transmission to different snake species (Boa constrictor and Lamprophis fuliginosus) and lizards (Lepidodactylus lugubris) was performed to assess the host specificity. Isolates were compared with Hepatozoon species from sub-Saharan reptiles and described as a new species based on the morphology, phylogenetic analysis, and a complete life cycle.
Assuntos
Boidae/parasitologia , Coccídios/classificação , Coccídios/crescimento & desenvolvimento , Coccidiose/veterinária , Culex/parasitologia , Insetos Vetores/parasitologia , Animais , Coccídios/patogenicidade , Coccidiose/parasitologia , Coccidiose/transmissão , DNA de Protozoário/análise , DNA de Protozoário/isolamento & purificação , Eritrócitos/parasitologia , Estágios do Ciclo de Vida , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Especificidade da EspécieRESUMO
African pythons (Pythonidae) and large vipers (Bitis spp.) act as definitive hosts for Armillifer armillatus and Armillifer grandis parasites (Crustacea: Pentastomida) in the Congo Basin. Since the proportion of snakes in bushmeat gradually increases, human pentastomiasis is an emerging zoonotic disease. To substantiate the significance of this threat, we surveyed snakes offered for human consumption at bushmeat markets in the Kole district, Democratic Republic of the Congo, for the presence of adult pentastomids. In Bitis vipers (n = 40), Armillifer spp. infestations exhibited an 87.5% prevalence and 6.0 median intensity. Parasite abundance covaried positively with viper length, but not with body mass. In pythons (n = 13), Armillifer spp. exhibited a 92.3% prevalence and 3.5 median intensity. The positive correlations between parasite abundance and python length or mass were statistically nonsignificant. Ninety-one percent of A. grandis were discovered in vipers and 97% of infected vipers hosted A. grandis, whereas 81% of A. armillatus specimens were found in pythons and 63% of infected pythons hosted A. armillatus. Thus, challenging the widespread notion of strict host specificity, we found 'reversed' infections and even a case of coinfection. In this study, we also gathered information about the snake consumption habits of different tribal cultures in the area. Infective parasite ova likely transmit to humans directly by consumption of uncooked meat, or indirectly through contaminated hands, kitchen tools or washing water.
Assuntos
Boidae/parasitologia , Carne/parasitologia , Doenças Parasitárias em Animais/epidemiologia , Pentastomídeos/parasitologia , Viperidae/parasitologia , Animais , Congo/epidemiologia , Parasitologia de Alimentos , Doenças Parasitárias em Animais/transmissão , Prevalência , Zoonoses/epidemiologia , Zoonoses/transmissãoRESUMO
BACKGROUND: Species of the genus Borrelia are causative agents of Lyme disease and relapsing fever. Lyme disease is the most commonly reported vector-borne disease in the northern hemisphere. However, in some parts of the world Lyme borreliosis and relapsing fever may be caused by novel Borrelia genotypes. Herein, we report the presence of a Borrelia sp. in an Amblyomma varanense collected from Python reticulatus. METHODS: Ticks were collected from snakes, identified to species level and examined by PCR for the presence of Borrelia spp. flaB and 16S rRNA genes. Phylogenetic trees were constructed using the neighbour-joining method. RESULTS: Three A. varanense ticks collected from P. reticulatus were positive for a unique Borrelia sp., which was phylogenetically divergent from both Lyme disease- and relapsing fever-associated Borrelia spp. CONCLUSION: The results of this study suggest for the first time that there is a Borrelia sp. in A. varanense tick in the snake P. reticulatus that might be novel.
Assuntos
Boidae/parasitologia , Borrelia/genética , Ixodidae/microbiologia , Doença de Lyme/microbiologia , Filogenia , Febre Recorrente/microbiologia , Infestações por Carrapato/veterinária , Animais , RNA Bacteriano/genética , RNA Ribossômico 16S/genéticaRESUMO
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/patologiaRESUMO
Oral inoculations of 9 litter-groups of 3 5-day-old suckling BALB/c mouse pups (Mus musculus) with 6.7 x 10(3) to 1.2 x 10(5) per pup of viable, Cryptosporidium serpentis oocysts from snakes resulted in no transmission. Mice showed normal development; the litter-group weight gain was not altered significantly (P > 0.05) relative to the total number of C. serpentis oocysts inoculated or to the initial group weight (P > 0.05). Histological sections of stomach, duodenum, jejunum, ileum, cecum, and colon 4 days postinoculation did not contain life-cycle stages of Cryptosporidium in any inoculated mice. Because these neonatal, C. parvum-susceptible BALB/c mice were resistant to infection it is unlikely that C. serpentis transmission to the snakes "via infected prey" results when captive snakes are maintained on a diet of BALB/c mice.
Assuntos
Animais de Zoológico/parasitologia , Boidae/parasitologia , Criptosporidiose/transmissão , Ração Animal/parasitologia , Animais , Animais Recém-Nascidos , Fezes/parasitologia , Parasitologia de Alimentos , Camundongos , Camundongos Endogâmicos BALB CRESUMO
Patterns of genetic variation for the tick Amblyomma dissimile were analyzed from a total of 200 ticks collected on 12 toads (Bufo marinus), 14 snakes (Boa constrictor), and 8 lizards (Iguana iguana) at 11 localities. The analyses were performed on electrophoretic data from 8 isozyme loci. Mean heterozygosity per locus was 6% (+/-3.1) per population. Differences in allelic frequencies among ticks from different individual hosts were the major source of genetic variability in this study. Host species was a smaller source of genetic variation. Genetic distances between localities varied according to which host species was present in each locality, and these appeared to be related to the extent of habitat overlap between host species. The smallest genetic distances between samples from different host species were recorded for I. iguana and B. constrictor. In contrast, the genetic distances between tick samples from B. marinus and either of the reptile species were significantly larger than between tick samples from this amphibian species. Ecological variables or the geographic distance did not explain the local patterns of differentiation observed in A. dissimile. Major genetic differences between island and mainland sites (0.03702) suggested an association between genetic distances and geographic isolation. The consistency between patterns of genetic variation and those of host home range overlap suggests that host dispersion is the main force structuring the genetic variation within this tick species.
Assuntos
Variação Genética , Carrapatos/genética , Alelos , Animais , Boidae/parasitologia , Bufo marinus/parasitologia , Intervalos de Confiança , Feminino , Frequência do Gene , Genética Populacional , Heterozigoto , Iguanas/parasitologia , Isoenzimas/genética , Masculino , Infestações por Carrapato/parasitologia , Infestações por Carrapato/veterinária , Carrapatos/enzimologia , VenezuelaRESUMO
Molecular methods were used to identify blood parasites frequently observed in blood smears of water pythons (Liasis fuscus) captured in our study area in the Northern Territory of Australia. A nested polymerase chain reaction (PCR) using primers amplifying the 18s ribosomal RNA (rRNA) nuclear gene resulted in a short PCR product (180 bp) matching this region in the genus Hepatozoon. However, because of the short sequence obtained. 2 new primers were designed based on 18s rRNA sequences of 3 Hepatozoon taxa available in GenBank. Using these primers, approximately 600 bp of the parasite's 18s rRNA gene was amplified successfully and sequenced from 2 water python samples. The new primers were used to investigate the prevalence of blood parasites in 100 pythons. In 25 of these samples we did not observe any blood parasites when examining stained slides. All the samples revealed a 600-bp PCR product, demonstrating that pythons in which we did not visually observe any parasites were infected by Hepatozoon spp. We also analyzed the nucleotide sequences of blood parasites in 4 other reptile taxa commonly encountered in our study area. The sequences obtained from water pythons and from 1 of these taxa were identical, suggesting that the parasite is capable of infecting hosts at different taxonomic levels.