Morphological and molecular characterization of Eustrongylides excisus larvae (Nematoda: Dioctophymatidae) in Sander lucioperca (L.) from Northern Turkey.

The genus Eustrongylides Jägerskiöld, 1909 includes parasitic nematodes (Dioctophymatidae) affecting various fish species and piscivorous birds of freshwater ecosystems. Currently, there is little information on the molecular characterization of E. excisus based on nuclear ribosomal internal transcribed spacer (ITS) rDNA regions. However, before the present study, there had been no reports of characterizing the E. excisus using nuclear small subunit ribosomal RNA (SSU rRNA) and mitochondrial cytochrome c oxidase subunit I (COI) genes sequences. In the present study, Eustrongylides spp. larvae were collected from pike-perch Sander lucioperca (L.) in Northern Turkey, and characterized by sequencing of ITS regions, SSU rRNA, and COI markers. Larvae herein morphologically identified as the fourth stage of Eustrongylides spp. were genetically identified as E. excisus based on the ITS sequence analysis. This study is the first record of SSU rRNA and COI sequences for E. excisus in GenBank. This is also a molecular characterization of E. excisus for the first time in Turkey. The ITS, SSU rRNA, and COI sequences of E. excisus can be used to establish the phylogenetic relationships of Eustrongylides species from Turkey and worldwide for further studies.

Abdominal dioctophymosis in a domestic cat from the Peruvian rainforest confirmed morphologically and molecularly.

A case of abdominal dioctophymosis in a domestic cat was found in San Juan Bautista district, the Peruvian rainforest, in the Loreto department of Peru. The pet went to a veterinary clinic for a routine ovariohysterectomy during which a large nematode was found in the abdominal cavity. The nematode was morphologically identified as an adult female of Dioctophyme sp. A few morphological parameters, such as the vagina distance from the anterior part and the egg size, were different than D. renale. Partial sequences of the cytochrome c oxidase subunit I (cox1) and the small subunit 18S ribosomal RNA genes were compared with the references from public sequence database and showed a genetic identifies of 89.25% and 99.65% with D. renale, respectively. This is the first mitochondrial molecular analysis of a Dioctophyme specimen from South America and the results showed up to 12.5% nucleotide sequence variation in cox 1 gene of D. renale.

Eustrongylides sp. (Nematoda, Dioctophymatoidea) parasitizing Hoplias malabaricus (Actinopterygii: Erythrinidae) collected from the state of Rio de Janeiro, Brazil / Eustrongylides sp. (Nematoda, Dioctophymatoidea) parasitando Hoplias malabaricus (Actinopterygii: Erythrinidae) coletados do Estado do Rio de Janeiro, Brasil

Abstract Hoplias malabaricus (Characiformes, Erythrinidae), trahira, is a neotropical freshwater fish of economic and public health significance. A total of 45 specimens of H. malabaricus commercialized in the municipality of Magé, state of Rio de Janeiro, Brazil, were acquired between April 2016 and April 2018 to investigate the presence of nematode larvae. Twenty of the fish were found parasitized by 347 fourth-stage nematode larvae identified taxonomically as Eustrongylides sp. using morphological, morphometric and molecular data. The parasitic indices were: prevalence 44.44%, mean intensity 17.35, mean abundance 7.71, and range of infection 2-40. Infection sites were musculature, mesentery, abdominal cavity, and serosa of intestine, stomach and liver. This is the first report of Eustrongylides sp. larvae parasitizing H. malabaricus in the state of Rio de Janeiro.

Resumo Hoplias malabaricus (Characiformes, Erythrinidae), traíra, é um peixe neotropical de água doce que tem significante impacto na economia e saúde pública. De abril de 2016 a abril de 2018, foram adquiridos 45 espécimes de H. malabaricus comercializados no município de Magé, Estado do Rio de Janeiro, Brasil. Os peixes foram necropsiados e filetados para investigação da presença de larvas de nematoides. Vinte dos peixes coletados estavam parasitados por 347 larvas de nematoides, identificadas taxonomicamente como larvas de quarto estágio de Eustrongylides sp. usando-se dados morfológicos, morfométricos e moleculares, apresentando os seguintes valores: prevalência de 44,44%, intensidade média de 17,35, abundância média de 7,71, e amplitude de variação da infecção de 2-40. Os sítios de infecção foram musculatura, mesentério, cavidade abdominal e serosas do intestino, estômago e fígado. Este é o primeiro registro de larvas de Eustrongylides sp. parasitando H. malabaricus no Estado do Rio de Janeiro.

Morphological and Molecular Characterization of Larval and Adult Stages of Eustrongylides excisus (Nematoda: Dioctophymatoidea) with Histopathological Observations.

The genus Eustrongylides includes nematodes known as the etiological agent of the "big red worm disease." The aim of this work was to identify Eustrongylides spp. larvae from fish and adults from great cormorant (Phalacrocorax carbo) sampled at Lake Trasimeno, Italy, by morphological and molecular analysis. Histopathological description of the lesions in birds was also provided. We described adults of Eustrongylides excisus for the first time in Italy, and we also linked larval stages 3 and 4 to adults. The use of molecular tools combined with the traditional taxonomy will help the identification of the species, including species inquirendae. Moreover, molecular analysis can also help to investigate the role of intermediate and paratenic hosts, to deepen the knowledge about geographical distribution of the different Eustrongylides spp. and to define the zoonotic potential of E. excisus, which has not yet been identified as causal agent of human cases.

Eustrongylides sp. (Nematoda, Dioctophymatoidea) parasitizing Hoplias malabaricus (Actinopterygii: Erythrinidae) collected from the state of Rio de Janeiro, Brazil.

Hoplias malabaricus (Characiformes, Erythrinidae), trahira, is a neotropical freshwater fish of economic and public health significance. A total of 45 specimens of H. malabaricus commercialized in the municipality of Magé, state of Rio de Janeiro, Brazil, were acquired between April 2016 and April 2018 to investigate the presence of nematode larvae. Twenty of the fish were found parasitized by 347 fourth-stage nematode larvae identified taxonomically as Eustrongylides sp. using morphological, morphometric and molecular data. The parasitic indices were: prevalence 44.44%, mean intensity 17.35, mean abundance 7.71, and range of infection 2-40. Infection sites were musculature, mesentery, abdominal cavity, and serosa of intestine, stomach and liver. This is the first report of Eustrongylides sp. larvae parasitizing H. malabaricus in the state of Rio de Janeiro.

Occurrence of Dioctophyme renale larvae (Goeze, 1782) (Nematoda: Enoplida) in a new host from southern Brazil / Novo hospedeiro de larvas de Dioctophyme renale (Goeze, 1782) (Nematoda: Enoplida) no extremo sul do Brasil

Abstract Dioctophymatosis is caused by the giant kidney worm Dioctophyme renale which occurs in dogs, cats, and wild mammals. In Brazil, the disease has been diagnosed in dogs from several states around the country. In the present study, the occurrence of D. renale larvae in snakes from southern of Brazil is reported. Three specimens of Philodryas patagoniensis (Serpentes: Dipsadidae) (common names in Brazil: "parelheira", "papa-pinto") roadkill in the county of Capão do Leão, State of Rio Grande do Sul, southern Brazil, were necropsied. Two third-stage larvae of D. renale were found in the coelomic cavity of P. patagoniensis. This study reveals a new host for D. renale larvae in the southern region of the State of Rio Grande do Sul, Brazil. This particular geographic area of the country has stood out as several cases of D. renale infection have been reported in a number of vertebrates from this region including domestic dogs and cats and wild animals such as carnivores, fish, and freshwater turtles.

Resumo Dioctophyme renale, verme gigante do rim, parasita cães, gatos e mamíferos silvestres, sendo que no Brasil, a dioctofimatose canina vem sendo diagnosticada em diversos estados brasileiros. O estudo tem por objetivo registrar larvas de D. renale parasitando serpente no extremo sul do Brasil. Nesse contexto, foram examinados três espécimes de Philodryas patagoniensis (Serpentes: Dipsadidae) encontradas mortas após atropelamento em uma estrada do município de Capão do Leão, Rio Grande do Sul (RS). Duas larvas de terceiro estágio de D. renale foram encontradas na cavidade celomática de P. patagoniensis, a qual representa um novo hospedeiro para larvas de D. renale na região sul do RS, a qual vem se destacando devido aos diversos registros do parasito em cães e gatos domésticos, bem como animais silvestres (carnívoros, peixes, quelônios).

Occurrence of Dioctophyme renale larvae (Goeze, 1782) (Nematoda: Enoplida) in a new host from southern Brazil.

Dioctophymatosis is caused by the giant kidney worm Dioctophyme renale which occurs in dogs, cats, and wild mammals. In Brazil, the disease has been diagnosed in dogs from several states around the country. In the present study, the occurrence of D. renale larvae in snakes from southern of Brazil is reported. Three specimens of Philodryas patagoniensis (Serpentes: Dipsadidae) (common names in Brazil: "parelheira", "papa-pinto") roadkill in the county of Capão do Leão, State of Rio Grande do Sul, southern Brazil, were necropsied. Two third-stage larvae of D. renale were found in the coelomic cavity of P. patagoniensis. This study reveals a new host for D. renale larvae in the southern region of the State of Rio Grande do Sul, Brazil. This particular geographic area of the country has stood out as several cases of D. renale infection have been reported in a number of vertebrates from this region including domestic dogs and cats and wild animals such as carnivores, fish, and freshwater turtles.

Cutaneous emergence of Eustrongylides in two persons from South Sudan.

Two large, living worms were collected as they emerged from the lower limb of each of two persons in South Sudan. The worms were observed by staff of the South Sudan Guinea Worm Eradication Program during surveillance activities in communities at-risk for cases of Guinea worm disease (dracunculiasis). The worms measured 7 and 8 cm in length and were identified as fourth-stage larvae of Eustrongylides. This is the first report of such worms emerging from the skin; all five previous reports of human infection involved surgical removal of worms from the peritoneal cavity.

Molecular phylogeny and host specificity of the larval Eustrongylides (Nematoda: Dioctophmidae) from freshwater fish in China.

The nematodes Eustrongylides spp. collected from different fish species in China were examined for their intra- and interspecific evolutionary variations using the molecular markers mitochondrial cytochrome oxidase c subunit 1 (COI) gene and internal transcribed spacer (ITS) rDNA regions. The phylogenetic analysis indicated that Eustrongylides species are divided into 3 well-supported clades. The ITS divergence between the clades suggested that clades 2 and 3 might represent the same species, whereas clade 1 represent another cryptic species. The host specificity of these nematodes was analyzed according to prevalence data, host range, and phylogenetic information. Clade 1 was found in 4 fish species, i.e., Odontobutis obscurus, Silurus asotus, Culter mongolicus, and Acanthogobius flavimanus, but was predominant in the 2 perciform species, O. obscurus and A. flavimanus. Clade 2 was found in 3 fish species, Monopterus albus, Channa argus, and Channa asiatica, but was predominant in M. albus, reported to feed primarily on oligochaetes, the first intermediate host of Eustrongylides sp. Clade 3 was found in 9 species, but its low prevalence suggests accidental infection in all species. Although the larval nematode presented low host specificity, it exhibited some host preference.

Dioctophyme renale (Nematoda: Dioctophymatoidea) in the abdominal cavity of Rattus norvegicus in Japan.

We collected 24 brown rats, Rattus norvegicus, in Kanagawa Prefecture in Japan and found one rat harboring a dioctophymatid nematode. A single male and a female worm were recovered from the abdominal cavity and were identified as Dioctophyme renale based on morphologic features and a BLAST DNA sequence analysis. We describe the morphological features of the adult worms and eggs from this extremely rare case of D. renale infection in a brown rat.

Fatal bilateral dioctophymatosis.

Dioctophyma renale is a parasite that frequently occurs in animals but rarely in humans. The present report describes the clinical observations of a D. renale infection in a 51-yr-old woman. Its clinical signs and diagnostic findings were unspecific until giant worms were observed in the urine and histological findings confirmed it was a D. renale infection. She refused treatment and died of bilateral renal function failure. This is the first confirmed report to follow the natural progression of D. renale infection in a human. Here, we discuss a conservative therapeutic approach and features associated with this parasitic infection.

Dioctophyme renale (Goeze, 1782) in the abdominal cavity of a domestic cat from Brazil.

This study reports a case of parasitism by the giant kidney worm, Dioctophyme renale (Goeze, 1782), in the abdominal cavity of a domestic cat from Brazil. A female adult cat presenting prostration, dehydration, physical debility, pronounced jaundice and ascitis, was taken to the Department of Animal Parasitology of the Veterinary Institute of the Universidade Federal Rural do Rio de Janeiro, Brazil. Clinical signs suggested a case of peritonitis. The cat's clinical condition was grave and death occurred within a few days. During necropsy, a brownish-red nematode, 24.9cm long, was found in the abdominal cavity and was identified as a male adult D. renale. This study reports the first confirmed case of dioctophymatosis in the domestic cat. The parasite's aberrant location in the abdominal cavity suggests that the domestic cat is not a suitable host.

Geographic and host range of the nematode Soboliphyme baturini across Beringia.

The nematode Soboliphyme baturini Petrov, 1930, was found to represent a single species with a relatively broad geographic range across Beringia and northwestern North America on the basis of the assessment of molecular sequence data for adult and juvenile parasites. Refuted are hypotheses suggesting that several cryptic species could be partitioned either among an array of mustelid definitive hosts or across the vast region that links North America and Eurasia. Host specificity for this species is examined on the basis of a comprehensive list for definitive hosts, derived from new field surveys and existing literature for S. baturini. Only 5 mustelids (Gulo gulo, Martes americana, M. caurina, M. zibellina, and Neovison vison) appear to have significant roles in the life history, persistence, and transmission of this nematode. Soboliphyme baturini readily switches among M. americana, M. caurina, Mustela erminea, or N. vison at any particular locality throughout its geographic range in North America, although Martes spp. could represent the source for nematodes in a broader array of mustelids. Molecular analyses (243 base pairs of mitochondrial gene nicotinamide dehydrogenase [ND4]) suggest that hypotheses for host specificity across an array of mustelid definitive hosts are not supported. The life cycle of S. baturini is explored through a review of diet literature for 2 marten species, M. americana and M. caurina, and other mustelids across the Holarctic. Shrews (Soricomorpha: Soricidae) comprise >8% of prey for these species of Martes, suggesting their putative role as paratenic hosts. Juvenile nematodes found in the diaphragms of soricids are genetically identical to adult S. baturini found in the stomachs of mustelids at the same locations in both Asia and North America, corroborating a role in transmission for species of Sorex.

Eustrongylides sp. (Nematoda: Dioctophymatoidea) from the stomach of a Nile crocodile, Crocodylus niloticus Laurenti, 1768, in Botswana.

During a study conducted between 2003 and 2005 on the diet of Nile crocodiles in Botswana, two young adult nematodes, one male and one female, belonging to the genus Eustrongylides Jägerskiöld, 1909 were recovered from the stomach contents of one of these animals. The caudal bursa of the male is present and the ejaculatory duct could be identified, but the spicule could not be seen. The vulva of the female has opened and the anus is situated on a terminal protruberance. Measurements and drawings of these specimens are provided, together with some data on the occurrence and life-cycles of members of the genus Eustrongylides in crocodilians world-wide and in African hosts in particular. Piscivorous birds are the usual final hosts of these nematodes. It is probable that the specimens described herein had developed in a paratenic fish host, and that the latter had been eaten by the crocodile.