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1.
Parasitol Res ; 123(1): 56, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38105374

RESUMO

The microbiome plays an important role in health, where changes in microbiota composition can have significant downstream effects within the host, and host-microbiota relationships can be exploited to affect health outcomes. Parasitic helminths affect animals globally, but an exploration of their microbiota has been limited, despite the development of anti-Wolbachia drugs to help control infections with some filarial nematodes. The equine ascarids, Parascaris spp., are considered the most pathogenic nematodes affecting juvenile horses and are also the only ascarid parasite to have developed widespread anthelmintic resistance. The aim of this study was to characterize the microbiota of this helminth, focusing on the female gonad, determine a core microbiota for this organ, identify bacterial species, and show bacterial localization to the female gonad via in situ hybridization (ISH). A total of 22 gonads were isolated from female Parascaris spp. collected from three foals, and 9 female parasites were formalin-fixed and paraffin-embedded for ISH. Next-generation sequencing was performed using V3-V4 primers as well as the Swift Amplicon™ 16S+ ITS Panel. Overall, ten genera were identified as members of the Parascaris spp. female gonad and twelve bacterial species were identified. The most prevalent genus was Mycoplasma, followed by Reyranella, and there were no differences in alpha diversity between parasites from different horses. Specific eubacteria staining was identified in both the intestine and within the gonad using ISH. Overall, this study provided in-depth information regarding the female Parascaris spp. microbiota and was the first to identify the core microbiota within a specific parasite organ.


Assuntos
Infecções por Ascaridida , Ascaridoidea , Helmintos , Doenças dos Cavalos , Parasitos , Animais , Cavalos , Feminino , Ascaridoidea/genética , Doenças dos Cavalos/parasitologia , Infecções por Ascaridida/veterinária , Infecções por Ascaridida/parasitologia , Resistência a Medicamentos , Fezes/parasitologia , Gônadas
2.
Ecohealth ; 20(3): 263-272, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37971598

RESUMO

The raccoon roundworm (Baylisascaris procyonis), a gastrointestinal nematode of the raccoon (Procyon lotor), may cause a severe form of larva migrans in humans, which can lead to death or permanent neurological damage. Although roundworms were inadvertently introduced to Europe alongside their raccoon hosts, the parasite is not present in every raccoon population. It is important to understand the geographic distribution of B. procyonis, as early and rapid treatment can prevent severe pathologies in humans. We present evidence for the roundworm spreading into a naive raccoon population through natural dispersal of infected raccoons. We sampled 181 raccoons from Saxony-Anhalt, a German federal state containing contact zones of different raccoon populations, two of which were previously free of the parasite. We screened the raccoons for roundworms and used microsatellite-based assignment tests to determine the genetic origin of the raccoons and their parasites. We detected roundworms in 16 of 45 raccoons sampled in a previously roundworm-free area in the northern part of the state. The largest proportion of the genetic ancestry (≥ 0.5) of the 16 raccoon hosts was assigned to the previously naive raccoon population. Conversely, the genetic ancestry of almost all the roundworms was assigned to the nearest roundworm population in the southern part of the state. Infected raccoons have, therefore, spread to the north of the state, where they interbred with and infected local raccoons. It seems likely that the roundworms will continue to spread. Health authorities should consider continuous surveillance programmes of naive populations and raise public awareness.


Assuntos
Infecções por Ascaridida , Ascaridoidea , Animais , Humanos , Guaxinins/parasitologia , Infecções por Ascaridida/epidemiologia , Infecções por Ascaridida/veterinária , Infecções por Ascaridida/parasitologia , Ascaridoidea/genética , Europa (Continente)
3.
Parasit Vectors ; 16(1): 202, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37322493

RESUMO

BACKGROUND: The roundworms, Parascaris spp., are important nematode parasites of foals and were historically model organisms in the field of cell biology, leading to many important discoveries. According to karyotype, ascarids in Equus are commonly divided into Parascaris univalens (2n = 2) and Parascaris equorum (2n = 4). METHODS: Here, we performed morphological identification, karyotyping and sequencing of roundworms from three different hosts (horses, zebras and donkeys). Phylogenetic analysis was performed to study the divergence of these ascarids based on cytochrome c oxidase subunit I (COI) and internal transcribed spacer (ITS) sequences. RESULTS: Karyotyping, performed on eggs recovered from worms of three different Equus hosts in China, showed two different karyotypes (2n = 2 in P. univalens collected from horses and zebras; 2n = 6 in Parascaris sp. collected from donkeys). There are some differences in the terminal part of the spicula between P. univalens (concave) and Parascaris sp. (rounded). Additionally, it was found that the egg's chitinous layer was significantly thicker in Parascaris sp. (> 5 µm) than P. univalens (< 5 µm) (F(2537) = 1967, P < 0.01). Phylogenetic trees showed that the sequences of Parascaris from Equus hosts were divided into two distinct lineages based on sequences of the COI and ITS. CONCLUSIONS: Comparing the differences in roundworms collected from three different Equus hosts, this study describes a Parascaris species (Parascaris sp.) with six chromosomes in donkeys. It is worth noting that the thickness of the chitinous layer in the Parascaris egg may serve as a diagnostic indicator to distinguish the two roundworms (P. univalens and Parascaris sp.). The Parascaris sp. with six chromosomes in donkeys in the present study may be a species of P. trivalens described in 1934, but the possibility that it is a new Parascaris species cannot be ruled out. Both karyotyping and molecular analysis are necessary to solve the taxonomic problems in Parascaris species.


Assuntos
Infecções por Ascaridida , Ascaridoidea , Doenças dos Cavalos , Cavalos , Animais , Ascaridoidea/genética , Filogenia , Infecções por Ascaridida/veterinária , Infecções por Ascaridida/parasitologia , Doenças dos Cavalos/parasitologia , Equidae , China
4.
J Wildl Dis ; 59(2): 347-352, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-37074793

RESUMO

Baylisascaris procyonis, or raccoon roundworm, is an intestinal nematode parasite of raccoons (Procyon lotor) that is important to public and wildlife health. Historically, the parasite was uncommon in the southeastern US; however, the range of B. procyonis has expanded to include Florida, US. From 2010 to 2016, we opportunistically sampled 1,030 raccoons statewide. The overall prevalence was 3.7% (95% confidence interval=2.5-4.8%) of sampled individuals, and infection intensity ranged from 1 to 48 (mean±standard deviation 9.9±4.0). We found raccoon roundworm in 9/56 (16%) counties sampled, and the percent positive ranged from 1.1% to 13.3% of specimens collected per county. Including previously published data, B. procyonis was detected in 11 Florida counties. We used logistic regression to estimate the contribution of raccoon demographic variables and the presence of the endoparasite Macracanthorhynchus ingens to B. procyonis detection in Florida. Following the model selection process we found housing density, M. ingens presence, and urbanicity to be predictive of raccoon roundworm presence. We also found substantial among-county variation. Raccoon sex and age were not useful predictors. Public health officials, wildlife rehabilitators, wildlife managers, and others should consider any Florida raccoon to be potentially infected with B. procyonis, particularly in areas where housing density is high.


Assuntos
Infecções por Ascaridida , Ascaridoidea , Animais , Florida/epidemiologia , Guaxinins/parasitologia , Infecções por Ascaridida/epidemiologia , Infecções por Ascaridida/veterinária , Infecções por Ascaridida/parasitologia , Animais Selvagens
5.
Parasitol Int ; 92: 102693, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36272657

RESUMO

The new nematode species, Falcaustra hanzaki n. sp. and Urodelnema takanoensis n. sp. (Cosmocercoidea: Kathlaniidae), were found from the intestine of giant salamanders in Kyoto Prefecture, Japan. The first species is featured by the number and arrangement of caudal papillae (3 pairs of precloacal papillae, 8 pairs of postcloacal papillae and a single ventral precloacal papilla), the presence of a single pseudosucker, spicules equal in size (520-638 µm long), and V-shaped gubernaculum in males; vulva situated about 3/5 of a body in females. The second species is characterized by the number and arrangement of caudal papillae (5 pairs of precloacal papillae, 6 pairs of postcloacal papillae and a single ventral precloacal papilla), spicules equal in size (403-593 µm long), V-shaped gubernaculum in males; vulva situated about 3/5 of a body in females. The molecular phylogenetic analysis was performed using the partial 18S and 28S ribosomal DNA and the internal transcribed spacers 1 region in the nuclear DNA. This phylogenetic study raised a question about the validity of Family Kathlaniidae and related families of Cosmocercoidea.


Assuntos
Infecções por Ascaridida , Ascaridídios , Nematoides , Animais , Feminino , Masculino , Urodelos/parasitologia , Filogenia , Ascaridídios/genética , Infecções por Ascaridida/parasitologia
6.
Parasit Vectors ; 15(1): 24, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-35022078

RESUMO

Baylisascaris procyonis is a nematode parasite of the raccoon (Procyon lotor), and it can be responsible for a severe form of larva migrans in humans. This parasite has been reported from many countries all over the world, after translocation of its natural host outside its native geographic range, North America. In the period between January and August 2021, 21 raccoons were cage-trapped and euthanized in Tuscany (Central Italy), in the context of a plan aimed at eradicating a reproductive population of this non-native species. All the animals were submitted for necroscopic examination. Adult ascariids were found in the small intestine of seven raccoons (prevalence 33.3%). Parasites have been identified as B. procyonis based on both morphometric and molecular approaches. The aim of the present article is to report the first finding of this zoonotic parasite from Italy, highlighting the sanitary risks linked to the introduction of alien vertebrate species in new areas.


Assuntos
Infecções por Ascaridida/veterinária , Ascaridoidea/isolamento & purificação , Guaxinins/parasitologia , Zoonoses/parasitologia , Animais , Infecções por Ascaridida/epidemiologia , Infecções por Ascaridida/parasitologia , Feminino , Intestinos/parasitologia , Espécies Introduzidas , Itália/epidemiologia , Masculino , Zoonoses/epidemiologia
7.
Transbound Emerg Dis ; 69(4): 2191-2200, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34227236

RESUMO

The geographic range of the zoonotic raccoon roundworm (Baylisascaris procyonis) is expanding together with the range of its host, the raccoon (Procyon lotor). This creates a new public health risk in parts of Europe where this parasite was previously absent. In the Netherlands, a raccoon population is becoming established and incidental findings of B. procyonis have been reported. To assess the risk to public health, the prevalence of B. procyonis was determined in the province of Limburg, where currently the largest Dutch raccoon population is present, as well as in the adjoining region of southern Belgium. Furthermore, genetic methods were employed to assess invasion pathways of both the raccoon and B. procyonis to aid in the development of control measures. Macroscopic analysis of intestinal content and testing of faecal samples were performed to detect B. procyonis adults and eggs. The population genetics of both B. procyonis and its raccoon host were analysed using samples from central and northwestern Europe. B. procyonis was found in 14/23 (61%, 95% CI: 41%-78%) raccoons from Limburg, but was not detected in 50 Belgian raccoons. Genetic analyses showed that the majority of the Dutch raccoons and their roundworms were introduced through ex-captive individuals. As long as free-living raccoon populations originate from captivity, population control methods may be pursued. However, natural dispersal from the border regions will complicate prolonged population control. To reduce the public health risk posed by B. procyonis, public education to increase awareness and adapt behaviour towards raccoons is key.


Assuntos
Infecções por Ascaridida , Ascaridoidea , Infecções por Nematoides , Animais , Infecções por Ascaridida/epidemiologia , Infecções por Ascaridida/parasitologia , Infecções por Ascaridida/veterinária , Ascaridoidea/genética , Genética Populacional , Infecções por Nematoides/veterinária , Óvulo , Prevalência , Saúde Pública , Guaxinins
8.
Infect Genet Evol ; 96: 105123, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34688888

RESUMO

Cosmocercoid nematodes are common parasites in the digestive tract of amphibians. However, our knowledge of the species diversity, genetic data and molecular phylogeny of the superfamily Cosmocercoidea are far from being well understood. In the present study, large numbers of cosmocercoid nematodes were collected from the fine-spined frog Sylvirana spinulosa (Smith) (Anura: Ranidae) and the white-spotted thigh tree-frog Polypedates megacephalus (Hallowell) (Anura: Rhacophoridae) in Guangxi Province, China. Integrated morphological and genetic evidence reveals these nematode specimens to be a new species of the genus Aplectana, A. dayaoshanensis n. sp. (Cosmocercoidea: Cosmocercidae). The molecular characterization of small ribosomal DNA (18S), internal transcribed spacer (ITS) and large ribosomal DNA (28S) of A. dayaoshanensis n. sp., together with the 28S of A. chamaeleonis (Baylis, 1929) (collected from Hyperolius kivuensis Ahl in Rwanda), were reported for the first time. Moreover, phylogenetic analyses using maximum likelihood (ML) inference based on 18S + 28S and ITS sequence data, respectively, both supported the family Cosmocercidae to be a monophyletic group and the family Kathlaniidae to be a paraphyletic group. Our phylogenetic results rejected the monophyly of the genus Aplectana. The present results contribute to the knowledge of the species diversity and genetic data of cosmocercoid nematodes, and preliminarily revealed the phylogenetic relationships of the major families and some genera in the Cosmocercoidea.


Assuntos
Anuros , Infecções por Ascaridida/veterinária , Ascaridídios/classificação , Animais , Ascaridídios/anatomia & histologia , Ascaridídios/genética , Infecções por Ascaridida/parasitologia , China , Feminino , Masculino , Filogenia , Ranidae
9.
Parasitol Int ; 85: 102434, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34375752

RESUMO

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/parasitologia
10.
J Parasitol ; 107(4): 547-553, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34270759

RESUMO

The scarce information on the helminth fauna in otariids from the Southeastern Pacific comes mainly from stranded individuals or killed for that purpose. In this study, we compared the abundance and composition of enteroparasitic assemblages of Otaria flavescens using coprological techniques. Three sampling localities from north to south spanning 2,200 km off the Chilean coast were considered (Iquique, Viña del Mar, and Talcahuano). In all, 60 fecal samples were collected, and eggs belonging to 5 taxa were found in 91.6% of the samples. They were the anisakid nematodes Contracaecum and Pseudoterranova, the cestode Adenocephalus (syn. Diphyllobothrium), the trematode Ogmogaster, and the acanthocephalan Corynosoma. Samples from southern Chile (Talcahuano) showed the highest prevalence. Adenocephalus eggs had the highest prevalence and abundance in Iquique and Talcahuano, whereas Ogmogaster was the less prevalent and abundant in all sampling localities. Corynosoma eggs had similar prevalence and abundance among sampling localities, and Pseudoterranova eggs were absent in Iquique and with median prevalence values in Viña del Mar and Talcahuano. Thus, the composition of parasite egg assemblages was different between sampling localities. These differences between sampling localities may help to explain differential records of some zoonotic parasitoses such as pseudoterranovosis and diphyllobothriosis in Peru and Chile, where consumption of raw or marinated fish (ceviche) is common. For example, the lower diversity of parasite egg assemblages in the northern Chilean coast may be due to the absence or lower abundance of first intermediate/paratenic hosts of Pseudoterranova.


Assuntos
Infecções por Ascaridida/veterinária , Ascaridoidea/isolamento & purificação , Fezes/parasitologia , Enteropatias Parasitárias/veterinária , Leões-Marinhos/parasitologia , Zoonoses/parasitologia , Animais , Infecções por Ascaridida/epidemiologia , Infecções por Ascaridida/parasitologia , Ascaridoidea/classificação , Chile , Feminino , Enteropatias Parasitárias/epidemiologia , Enteropatias Parasitárias/parasitologia , Óvulo/classificação , Oceano Pacífico , Peru , Fatores de Risco , Zoonoses/epidemiologia
11.
Parasit Vectors ; 14(1): 246, 2021 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-33964977

RESUMO

BACKGROUND: Equine ascariosis, caused by Parascaris spp., is a worldwide endoparasitic disease affecting young horses in particular. Despite the great number of horses reared in Italy, large-scale epidemiological surveys dealing with ascariosis prevalence in the country are not reported in the current literature. For this reason, the present survey aims to describe, for the first time, the spread and infestation of Parascaris spp. in a large population of Italian horses (6896 animals) using faecal egg counts, and further to identify risk factors associated with ascarid egg shedding. METHODS: Individual rectal faecal samples collected during routine veterinary examinations were used and Parascaris spp. prevalence was tested against the animal's age, sex, housing conditions, geographic provenance as well as the respective sampling season. RESULTS: Among the examined stables, 35.8% showed at least one horse to be positive for Parascaris spp. eggs and an overall prevalence of 6.3% was found. Ascariosis rates tended to decrease significantly with age and, proportionally, 80.0% of the recorded Parascaris spp. eggs were found in 0.7% of the examined animals. Statistically significant differences among prevalence rates were found between the different geographic areas of provenance and prevalence was found to be higher in horses reared outdoors compared to those raised indoors. Analysis of data based on sex and season did not show any significant differences. Despite the lower prevalence found compared to other European countries, ascariosis was concluded to represent a significant health challenge for horses reared in Italy, especially foals. Age (foals and yearlings) and outdoor rearing were identified to be significant risk factors for Parascaris spp. egg shedding. Furthermore, the relevance of the infected horses over 6 years of age should not be underestimated as these represent a significant source of contamination for younger animals. CONCLUSIONS: The development of improved treatment protocols based on regular faecal examination combined with follow-up assessment of the efficacy of integrated action plans would prove beneficial in regard to animal health and anthelmintic resistance reduction in the field.


Assuntos
Infecções por Ascaridida/veterinária , Ascaridoidea/isolamento & purificação , Doenças dos Cavalos/parasitologia , Animais , Infecções por Ascaridida/diagnóstico , Infecções por Ascaridida/epidemiologia , Infecções por Ascaridida/parasitologia , Ascaridoidea/citologia , Fezes/parasitologia , Feminino , Doenças dos Cavalos/diagnóstico , Doenças dos Cavalos/epidemiologia , Cavalos , Itália/epidemiologia , Masculino , Óvulo/citologia , Contagem de Ovos de Parasitas
12.
Parasitol Int ; 84: 102380, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33984514

RESUMO

A wild adult male giant panda that was rescued from a nature reserve in Sichuan Province, China, has died. The panda had been in poor physical condition: it was wheezing and had increased serum amylase. A pathological examination was performed in order to determine the cause of death. Gross examination revealed 1380 mL of yellowish fluid in the abdominal cavity, 356 nematodes in the digestive tract and one filling the pancreatic duct, contractions and variably-sized dark purple areas in the spleen, a collapsed right lung and consolidation of the left lung. Acute pancreatitis was confirmed histopathologically via edema, focal necrosis and hemorrhage with inflammatory cell infiltration. Other major histopathological changes included serous-hemorrhagic pneumonia, lymphocytic necrosis and depletion in the spleen, and degeneration and necrosis of renal tubular epithelial cells. The nematodes were identified as Baylisascaris schroederi via molecular assays. In conclusion, the cause of death of the giant panda was determined to be multiple organ dysfunction syndrome caused by baylisascariasis-induced acute pancreatitis. To our knowledge, this is the first report of fatal baylisascariasis-induced acute pancreatitis in the giant panda.


Assuntos
Infecções por Ascaridida/veterinária , Ascaridoidea/isolamento & purificação , Pancreatite/veterinária , Ursidae , Doença Aguda , Animais , Animais de Zoológico , Infecções por Ascaridida/parasitologia , Infecções por Ascaridida/patologia , Análise Química do Sangue/veterinária , China , DNA de Helmintos/análise , Evolução Fatal , Testes Hematológicos/veterinária , Masculino , Pancreatite/parasitologia , Pancreatite/patologia , Análise de Sequência de DNA/veterinária
13.
Parasitol Int ; 83: 102365, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33901676

RESUMO

Porrocaecum angusticolle is a nematode species mainly parasitic in the birds of Accipitriformes and Strigiformes. However, some aspects of the morphology of P. angusticolle remain insufficiently known. In the present study, the detailed morphology of P. angusticolle was studied using light and, for the first time, scanning electron microscopy, based on newly collected specimens from the common buzzard Buteo buteo (Linnaeus) (Accipitriformes: Accipitridae) in Czech Republic. Some previously unreported morphological features of taxonomic significance were observed. The nuclear and mitochondrial DNA markers, including partial large ribosomal DNA (28S), complete internal transcribed spacer (ITS-1 + 5.8S + ITS-2), cytochrome c oxidase subunit 1 (cox1) and subunit 2 (cox2) of P. angusticolle were sequenced for molecular identification of this species. There was no intraspecific genetic variation detected in the 28S and ITS regions among different individuals of P. angusticolle, but low level of intraspecific nucleotide divergence was found in the cox1 (0.26-0.78%) and cox2 regions (1.0%). The 28S and cox2 of P. angusticolle were sequenced for the first time. Our molecular evidence supported the validity of both P. angusticolle and P. depressum. The newly obtained genetic data are helpful for further studies of DNA-based taxonomy, population genetics and phylogeny of the genus of Porrocaecum.


Assuntos
Infecções por Ascaridida/veterinária , Ascaridoidea/isolamento & purificação , Doenças das Aves/parasitologia , Falcões , Animais , Infecções por Ascaridida/parasitologia , Ascaridoidea/anatomia & histologia , Ascaridoidea/genética , Ascaridoidea/ultraestrutura , República Tcheca , DNA de Helmintos/análise , DNA Ribossômico/análise , Complexo IV da Cadeia de Transporte de Elétrons/análise , Feminino , Proteínas de Helminto/análise , Masculino , Microscopia/veterinária , Microscopia Eletrônica de Varredura/veterinária
14.
Parasitol Res ; 120(5): 1677-1686, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33754190

RESUMO

Different species of the genus Ophidascaris (Baylis, 1921; Nematoda: Ascaridida, Ascaridoidea) are intestinal parasites of various snake species. More than 30 Ophidascaris species have been reported worldwide; however, few molecular genetic studies have been conducted on this genus. We sequenced the complete mitogenome of Ophidascaris wangi parasitizing two snake species of the family Colubridae, i.e., Elaphe carinata (Günther, 1864) and Dinodon rufozonatum. The mitogenome sequence of O. wangi was approximately 14,660 base pairs (bp) long and encoded 36 genes, including 12 protein-coding genes (PCGs), 2 ribosomal RNA (rRNA) genes, and 22 transfer RNA genes. Gene arrangement, genome content, and transcription direction were in line with those in Toxascaris leonina (Linstow, 1902; Ascaridida: Ascarididae). Phylogenetics of O. wangi and other ascaridoids were reconstructed based on the concatenated amino acid sequences of 12 PCGs, and on nucleotide sequences of 12 PCGs and two rRNA genes. Phylogenetic analyses were performed using maximum likelihood and Bayesian inference methods, and the results suggested that O. wangi constitutes a sister clade of Ascaris, Parascaris, Baylisascaris, and Toxascaris within the family Ascarididae, which is a sister clade of Toxocaridae. The mitogenome sequence of O. wangi obtained from the present study will be useful for future identification of the nematode worms in the genus Ophidascaris and will increase the understanding of population genetics, molecular epidemiology, and phylogenetics of ascaridoid nematodes in snakes.


Assuntos
Infecções por Ascaridida/veterinária , Ascaridoidea/genética , Colubridae/parasitologia , Genoma Mitocondrial/genética , Animais , Infecções por Ascaridida/parasitologia , Ascaridoidea/classificação , Ascaridoidea/isolamento & purificação , China , Colubridae/classificação , DNA Mitocondrial/genética , Ordem dos Genes , Genes Mitocondriais/genética , Filogenia
15.
J Parasitol ; 107(1): 16-22, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33498083

RESUMO

Horses in Iceland have been isolated for more than 1,000 yr but still harbor a similar range of gastrointestinal parasites as do horses across the world. The long isolation of the horses and their parasites presumably means that no resistance genes have been introduced into the Parascaris spp. population. It is therefore of particular interest to investigate the efficacy of ivermectin on Parascaris spp. infecting Icelandic foals. Potential treatment failure of ivermectin in Iceland will add substantial new information on how resistance can arise independently. This study aimed to determine the efficacy of subcutaneous injection of ivermectin for the treatment of Parascaris spp. infection in foals and to identify the Parascaris species present in the west and north of Iceland. A fecal egg count reduction (FECR) test (FECRT) was performed on 50 foals from 8 farms, including an untreated control group of 6 foals, from September to November 2019. The foals were between 3 and 5 mo of age at the start of the study and had not previously been treated with anthelmintic drugs. Each foal was treated subcutaneously with off-label use of Ivomec® injection 10 mg/ml or Noromectin® 1% at a dose of 0.2 mg/kg. The FECR for each farm was calculated in 2 ways, by the eggCounts package in R and by the Presidente formula (FECRT). Both calculation methods resulted in efficacy levels between 0% and 80.78%, indicating ivermectin resistance on all farms. We also confirmed, by karyotyping, that the species of equine ascarid present in the west and north of Iceland is Parascaris univalens. This study provides evidence for treatment failure of ivermectin against P. univalens infection in foals. Since Icelandic horses have been isolated on the island for more than 1,000 yr, this implies that resistance alleles have developed independently in the Icelandic Parascaris population. The actual clinical impact of ivermectin resistance is unknown but another drug of choice should be considered to treat Parascaris infection in foals in Iceland.


Assuntos
Antiparasitários/farmacologia , Infecções por Ascaridida/veterinária , Ascaridoidea/efeitos dos fármacos , Doenças dos Cavalos/tratamento farmacológico , Doenças dos Cavalos/parasitologia , Ivermectina/farmacologia , Animais , Antiparasitários/uso terapêutico , Infecções por Ascaridida/tratamento farmacológico , Infecções por Ascaridida/parasitologia , Ascaridoidea/classificação , Teorema de Bayes , Resistência a Medicamentos , Fezes/parasitologia , Cavalos , Islândia , Ivermectina/uso terapêutico , Cariotipagem/veterinária , Contagem de Ovos de Parasitas/veterinária , Inquéritos e Questionários
16.
Parasitol Res ; 120(2): 461-480, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33409638

RESUMO

This study aimed to determine the integrative characterisation of nematodes from three species of edible flathead fishes (Scorpaeniformes: Platycephalidae) in New South Wales, Australia, and describe nematode communities within three species of flatheads. Tiger (Platycephalus richardsoni (Castelnau); n = 20) and sand flatheads (Platycephalus bassensis (Cuvier); n = 20), sourced from the Nelson Bay area, and dusky flathead (Platycephalus fuscus (Cuvier); n = 20) from the Manning River, Taree, were examined for the presence of nematodes. The nematodes were initially classified morphologically as 12 different morphotypes belonging to the families Anisakidae (Anisakis types I, II, and III, Contracaecum type II, Terranova types I and II), Raphidascarididae (Hysterothylacium types IV, VI, VIII, and H. zhoushanense larva), and Gnathostomatidae (Echinocephalus sp. larva), Capillariidae (Capillaria sp.), followed by genetic identification through sequencing of the internal transcribed spacer (ITS-1, 5.8S, ITS-2) regions. Phylogenetic analyses revealed the evolutionary relationship between the identified larval specimens in the present study with available GenBank larval and adult nematodes. Sand flathead was 90% infected with nematodes followed by tiger flathead at 85% and dusky flathead at 15%. Nematodes infecting estuarine dusky and oceanic sand and tiger flatheads contrasted markedly. The analysis of similarities (ANOSIM) showed significant differences (p < 0.001) in the composition of taxa within nematode communities between the three species of flatheads (global R = 0.208) with the highest difference being between sand and dusky flatheads (R = 0.308, p < 0.001). The findings of the present study provide a foundation for future investigations of the community composition, life cycles, and distribution of nematode populations in edible fish in Australia and explore and clarify their significance to public health.


Assuntos
Infecções por Ascaridida/veterinária , Ascaridoidea/isolamento & purificação , Biota , Perciformes/parasitologia , Alimentos Marinhos/parasitologia , Animais , Infecções por Ascaridida/parasitologia , Ascaridoidea/classificação , Ascaridoidea/genética , Ascaridoidea/crescimento & desenvolvimento , Larva/classificação , Larva/genética , Larva/crescimento & desenvolvimento , New South Wales , Filogenia , Especificidade da Espécie
17.
Integr Zool ; 16(6): 929-938, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32652769

RESUMO

Contracaecum species are economically important fish-borne larval nematodes with zoonotic significance. In June 2019, more than 100 piscivorous birds died in their habitats close to the Wild Duck Lake, located in Yanqing, northwest of Beijing, China. Post-mortem examination of Black Night Herons (Nycticorax) revealed the presence of numerous anisakid nematodes in the proventriculus. Recovered nematodes were identified as Contracaecum sp. based on morphological description. Phylogenetic analysis of the mitochondrial (mt) genome and the ITS gene showed that sequences of Contracaecum sp. Beijing isolates were grouped into a new individual cluster. Furthermore, the parasite was successfully isolated from fresh dead birds, feces of piscivorous birds, and fish and prevalence ranged from 8.0% to 81.8%. Consequently, our study demonstrated Contracaecum sp. infections in different sources from China, which might constitute a threat to wildlife, aquaculture, and public health.


Assuntos
Infecções por Ascaridida/veterinária , Ascaridoidea/genética , Doenças das Aves/parasitologia , Animais , Infecções por Ascaridida/epidemiologia , Infecções por Ascaridida/parasitologia , Doenças das Aves/epidemiologia , Aves , China/epidemiologia , Peixes/parasitologia , Parasitologia de Alimentos
18.
Spat Spatiotemporal Epidemiol ; 35: 100371, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33138952

RESUMO

Baylisascaris procyonis, the raccoon roundworm, is a parasite found throughout North America and parts of Europe. More than 150 species of mammals and birds including humans can develop neurological disease following infection with the larval stage of this parasite. To investigate whether B. procyonis infections in raccoons cluster in space, time, or space-time, we used data from 1353 Ontario raccoons submitted to the Canadian Wildlife Health Cooperative between 2013 and 2016. We identified a significant spatial cluster of increased infection prevalence in southern Ontario centered over a major metropolitan area, as well as a significant cluster of decreased infection prevalence in a primarily agricultural region in southwestern Ontario. Furthermore, we identified statistically significant temporal clusters in the fall in annual scans of data from 2014, 2015 and 2016. Examination of both Bernoulli and space-time permutation models for space-time analysis suggested that the purely spatial and temporal clusters were not explained by relatively short and spatially discrete events in space-time. The identified annual temporal clusters are consistent with previous research on the seasonality of B. procyonis infection in raccoons. Recognition of the spatial infection clusters will help identify potential geographic and anthropogenic factors associated with the occurrence of B. procyonis infection in raccoons. Given the zoonotic potential of this parasite, identification of a cluster of high infection prevalence in a major metropolitan area has implications for public education and risk management strategies.


Assuntos
Infecções por Ascaridida/epidemiologia , Ascaridoidea/isolamento & purificação , Guaxinins/parasitologia , Animais , Animais Selvagens , Infecções por Ascaridida/parasitologia , Humanos , Ontário/epidemiologia , Prevalência , Análise Espaço-Temporal , População Urbana , Zoonoses/prevenção & controle
19.
Artigo em Inglês | MEDLINE | ID: mdl-33174980

RESUMO

Lagochilascariasis is a neglected neotropical helminthiasis, responsible for human infections through the ingestion of raw or undercooked meat from wild animals infected by larvae encysted in their tissues. It is characterized by a chronic evolution with periods of remission and recurrences, affecting mainly the head and neck regions. It can progress to death by invasion of the central nervous system. It is caused by the Lagochilascaris minor nematode, first described in 1909 and mainly found in the Brazilian Amazon ecosystem, notably in Para State. In May 2010, a 15-year-old female, born in the city of Aveiro, Para State, was hospitalized in the city of Santarem, Para State, presenting with cervical and spinal abscesses and osteolytic lesions at T3-T5 level. During hospitalization, white larvae identified as L. minor were observed in a cervical subcutaneous fistula. After the surgical drainage of abscesses, albendazole 400 mg/day was started, with improvement of symptoms. The patient abandoned the follow-up and in January 2016, during the 20th week of pregnancy, she was readmitted to the Santarem Municipal Hospital with new cervical abscesses in the infra-mammary region, with numerous larvae exiting by subcutaneous left breast fistulas. The antiparasitic treatment was restarted due to possible reactivation of the infection in the spine and dissemination to the central nervous system. Ten weeks after hospital discharge, the patient had resolution of the fistulas and decreased abscesses, without gestational complications. This is the first case report of lagochilascariasis during pregnancy, as well as of involvement of mammary glands.


Assuntos
Abscesso/parasitologia , Infecções por Ascaridida/diagnóstico , Ascaridoidea/isolamento & purificação , Abscesso/diagnóstico , Adolescente , Adulto , Albendazol/administração & dosagem , Albendazol/uso terapêutico , Animais , Antibacterianos/uso terapêutico , Antiparasitários/administração & dosagem , Antiparasitários/uso terapêutico , Infecções por Ascaridida/tratamento farmacológico , Infecções por Ascaridida/parasitologia , Brasil , Drenagem , Ecossistema , Feminino , Humanos , Infecções por Nematoides/diagnóstico , Infecções por Nematoides/tratamento farmacológico , Infecções por Nematoides/parasitologia , Gravidez , Complicações Infecciosas na Gravidez , Adulto Jovem
20.
Infect Genet Evol ; 85: 104562, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32961362

RESUMO

The Japanese threadfin bream N. japonicus (Bloch) (Perciformes: Nemipteridae) is an important marine food fish in Asia. However, our present knowledge of the occurrence of its nematode parasites is still limited. In the present study, the species composition and infection rate of ascaridoid nematodes in N. japonicus from the South China Sea, were studied for the first time. Five ascaridoid species, namely Anisakis typica (L3), Hysterothylacium amoyense (L3), Hysterothylacium sp. IV-A (L3), adult of H. thalassini and Raphidascaris lophii (L3), were identified using integrative taxonomy. Hysterothylacium amoyense was the most prevalent species (prevalence 47.2%, mean intensity 14.9 ± 17.1). Hysterothylacium thalassini and R. lophii were reported in the Japanese threadfin bream for the first time. Two different genotypes of A. typica (overall prevalence of 3.4%; mean intensity 1.7 ± 0.9) were found in the South China Sea for the first time. The unique restriction polymorphism patterns of three species of Hysterothylacium are provided for rapid diagnosis. Our present results indicate that RFLP analysis of ITS region, using the restriction enzymes HhaI and RsaI, represents a simple and practical method for large-scale surveys of Hysterothylacium for seafood industry.


Assuntos
Infecções por Ascaridida/parasitologia , Ascaridoidea/classificação , Ascaridoidea/genética , Peixes/parasitologia , Alimentos Marinhos/parasitologia , Animais , Infecções por Ascaridida/diagnóstico , Infecções por Ascaridida/epidemiologia , Infecções por Ascaridida/transmissão , China/epidemiologia , Inocuidade dos Alimentos , Epidemiologia Molecular , Polimorfismo de Nucleotídeo Único , Zoonoses
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