Histopathological, morphological, and molecular characterization of fish-borne zoonotic parasite Eustrongylides Excisus infecting Northern pike (Esox lucius) in Iran.

Eustrongylides excisus is a fish-borne zoonotic parasite known to infect various fish species, including Northern pike (Esox Lucius). This nematode, belonging to the family Dioctophymatidae, has a complex life cycle involving multiple hosts. This study aimed to investigate the occurrence of Eustrongylides nematodes in Northern pike (E. Lucius) collected from Mijran Dam (Ramsar, Iran). Between June and October 2023, an investigation was conducted on Northern pike from Mijran Dam in Ramsar, Iran, following reports of reddish parasites in their muscle tissues. Sixty fish were examined at the University of Tehran, revealing live parasites in the muscles, which were then analyzed microscopically and preserved for a multidisciplinary study. The skeletal muscle tissues of 85% (51/60) of fish specimens were infected by grossly visible larvae which were microscopically identified as Eustrongylides spp. In histopathological examination, the lesion was composed of encapsulated parasitic granulomatous myositis. Microscopically, the cystic parasitic granulomas compressed the adjacent muscle fibers, leading to their atrophy and Zenker's necrosis. Moreover, epithelioid macrophages, giant cells and mononuclear inflammatory cells were present around the larvae and between the muscle fibers. Finally, a molecular analysis by examining the ITS gene region, revealed that they belong to the species E. excisus. Eustrongylidiasis in northern Iran necessitates further research into the biology, epidemiology, and control of Eustrongylides nematodes, focusing on various hosts. This study is the first to comprehensively characterize E. excisus in Northern pike in Ramsar, Iran, raising concerns about possible zoonotic transmission.

Genetic relatedness and diversity of Capillaria species infecting bayad (Bagrus bajad) in upper Egypt.

BACKGROUND: This study investigates the genetic characteristics of Capillaria isolates from the infected fish, Bagrus bajad, and their relation to human Capillaria philippinensis using Random Amplified Polymorphic DNA (RAPD-PCR) analysis. Fifteen fish Capillaria were isolated and compared to identified human C. philippinensis using six primers: M-are, M-1, G-7, G-11, G-15, and G-18. RESULTS: All six primers successfully amplified DNA, highlighting their efficacy in distinguishing between human and fish Capillaria isolates. The analysis revealed distinctive banding patterns between fish and human isolates, with variations in size and number of DNA fragments. Additionally, genetic similarity analysis showed intriguing patterns of relatedness, with certain pairs exhibiting high similarity percentages. Comparative assessment of RAPD polymorphism demonstrated consistent findings of 100% polymorphism across all primers. The Unweighted Pair Group Method with Arithmetic Mean Algorithm (UPGMA) evaluated the closest relationship between human and fish isolates. These results underscore the utility of RAPD analysis in delineating the genetic diversity among Capillaria isolates from different hosts. CONCLUSION: Overall, this study contributes to our understanding of the genetic variability and relatedness among Capillaria isolates, shedding light on their evolutionary dynamics and zoonotic potential.

Unusual parasitoses in urban dogs: Urinary capillariosis and linguatulosis, cases report.

Parasitic diseases caused by uncommonly diagnosed parasites may pose a threat to companion animals' health in urban environments where they are least expected. The pentastomid Linguatula serrata (tongue worm) and the capillarid Pearsonema plica (syn. Capillaria plica) are parasites with an indirect life cycle, infecting both domestic and wild carnivores. The present report describes two cases: the first one of urinary capillariosis and the other of linguatulosis, in two dogs living in the urban environment of Athens, Greece. In the case of capillariosis, the dog never lived out of the city, so it was presumably infected in the urban environment. On the contrary, in the case of linguatulosis, the dog was adopted at a young age from a rural environment but remained asymptomatic for several months while living in the city. Both dogs had mild symptoms, compatible with these infections. Urinary capillariosis and linguatulosis are uncommon in owned, pet dogs, living in cities due to epizootiological characteristics, i.e. need for wildlife reservoir for P. plica and consumption of raw infected viscera for L. serrata. Different factors contribute to the fact that such infections may occur in scenarios where they are least expected. Recent studies show a progressive worldwide increase in the number of uncommon parasitoses in pet animals, that in some cases, such as linguatulosis, are of zoonotic relevance. Regular parasitological examinations and preventive antiparasitic schemes are necessary in order to treat and prevent infections in pet animals and safeguard the health of both animals and humans under the concept of One Health.

Nephrectomy in 52 dogs for the treatment of Dioctophyme renale infection - Knowing the enemy to win.

Dioctophyme renale (D. renale) is a nematode that parasitizes the kidney of mammals. Treatment is often surgical, with removal of the affected organ. This retrospective study aims to evaluate the epidemiological, clinical, and surgical aspects, the interval between diagnosis and treatment, the occurrence of pre- and intraoperative complications, and the postoperative survival time of dogs parasitized by D. renale undergoing therapeutic nephrectomy. Records of fifty-two dogs treated in a single hospital service were analyzed. We collected epidemiological data, laboratory results, diagnostic method, anesthetic protocol, surgical technique and time, type of antimicrobial prophylaxis, pre- and intraoperative complications, location and number of parasites, and postoperative survival time. Of the 52 dogs undergoing right nephrectomy by laparotomy, 61.5 % were female and 63.4 % were adults. Although the most common clinical sign was hematuria (25 %), 61.5 % of the patients were asymptomatic. Eosinophilia and increased serum urea were the only laboratory changes found. The interval between diagnosis and surgery was 27.4 ± 23 days and no patient showed changes suggestive of surgical emergency. The most common surgical approach was the right paracostal (61.5 %), and a continuous suture pattern was predominant. Intraoperative complications occurred in 9.6 % of the procedures, varying from mild to severe hemorrhage. Mean postoperative survival was 835.5 ± 428 days. Dioctophymosis was effectively controlled by nephrectomy of the affected kidney, allowing a mean survival of more than 830 days. No serious complications caused by intervals between diagnosis and treatment have been reported. This is the largest retrospective study evaluating dogs infected with D. renale that were surgically treated.

Case report of hepatic calodiosis in a rescued dog.

Calodium hepaticum (syn. Capillaria hepatica) is a nematode responsible for parasitic zoonosis that can cause granulomatous lesions in the liver. Although murids are the main hosts, C. hepaticum has been documented in a wide range of mammals. Here, we report a case of hepatic calodiosis in a 6-month-old dog that was rescued in the municipality of Cuiabá, Mato Grosso state, midwestern Brazil. Even after being attended at a Veterinary Hospital, the case resulted in animal death. Necroscopic examination revealed significant macroscopic changes in the spleen, liver, and encephalus. Microscopic examination revealed parasitic eggs, identified as Calodium cf. hepaticum, that were rounded to oval with a bilamellar cuticle, radially striated, and with bipolar plugs. Considering the difficulty to diagnose this parasite, and the existence of diverse possible hosts in Mato Grosso due to the biodiversity of the state, further investigation is required to understand the true prevalence of C. hepaticum and the importance of this nematode in public health.

Gastrointestinal and respiratory parasites in captive mammals at Rabat zoo, with the first record of Capillaria spp. in the Fennec fox (Vulpes zerda).

The aim of the present study was to broaden the understanding of parasitism in captive wild mammals in Morocco. For this purpose, an investigation on gastrointestinal and respiratory parasites in African mammals from Rabat Zoo was carried out. A total of 47 fecal samples were collected from 30 species from November 2021 to March 2022 and examined macroscopically and microscopically. Parasites were detected in 21 species at a prevalence of 70%, with a parasite positivity rate of 89% in artiodactyls, 50% in perissodactyls, 67% in both carnivores and primates. No parasitic infection was detected in proboscideans. The most frequent infection was by nematodes with a percentage of 50%, followed by both protozoa and mixed infection with a prevalence of 10%. In conclusion, the results demonstrated that parasite prevalence remains high, even in enclosed spaces like zoos. Therefore, in order to ensure animal welfare and staff safety, sanitary measures should be implemented in such facilities, including routine diagnostic tests followed by appropriate treatment.

An unexpected cause of dysuria in a cat in Poland.

BACKGROUND: Urinary tract infestation by Capillaria spp. in domestic cats is rather rare, but can cause clinical symptoms and affect behaviour. To our knowledge, this report is the first to describe a case of urinary capillariosis in a cat in Poland. CASE PRESENTATION: A female formerly stray cat aged about 1.5 years showing dysuria, stranguria, periuria and lethargy was presented at the veterinary clinic. Urinalysis revealed the presence of Capillaria plica eggs in the sediment. The cat was treated successfully with three topical doses of Broadline (Merial, Toulouse, France). CONCLUSIONS: C. plica is a nematode whose definitive hosts are carnivores, which are infected by eating earthworms (the intermediate hosts). Thus, C. plica infestation is more frequent in wild carnivores and dogs, and rare in cats. Symptomatic bladder capillariosis in cats is very rarely diagnosed and described.

GIANT RED KIDNEY WORM (DIOCTOPHYMA RENALE) INFECTION IN PUPPIES LESS THAN FOUR MONTHS OF AGE FROM NORTHERN CANADA.

In this article, we present 2 case reports of puppies less than 4 mo of age at the time of infection with the nematode known as giant red kidney worm (Diotophyma renale). The first puppy was prepared for an ovariohysterectomy that evolved into an exploratory laparotomy. An inflamed omentum was observed, and D. renale infection was suspected due to the puppies' place of origin. The algorithm developed by the Ontario Society for the Prevention of Cruelty to Animals for the diagnosis and treatment of D. renale infections in dogs was followed. Both puppies had a history of origin from northern Manitoba, Canada. Due to the puppies' ages, the authors suspect that the transmission of infection for both puppies could be transmammary, transplacental, or ingestion of paratenic hosts or that these cases challenge what is thought to be the current prepatent period. In addition, D. renale infections in dogs, especially from northern communities, could be common.

Laparoscopic nephron-sparing surgery for the treatment of canine dioctophymosis.

This paper reports on two cases of laparoscopic nephrotomy employed in the treatment of canine dioctophymosis, which is considered a unusual procedure and a new treatment proposal heretofore not performed in veterinary medicine. Two patients were treated, one with a history of hematuria and the other with incidental finding of the parasite in the abdominal cavity during elective ovariohysterectomy. Both dogs were subjected to abdominal ultrasound, which produced images indicating the presence of the parasite in the right side kidney, but with partial parenchymal preservation. The patients were therefore subjected to laparoscopic nephrotomy. The surgical procedure was effective in treating dioctophymosis and enabled minimum tissue invasion during surgery, in addition to preservation of the kidney.

Dioctophyme renale in wandering dogs in Pelotas, South of Brasil.

This study aimed to verify the occurrence of Dioctophyme renale in stray dogs in the city of Pelotas, in the state of Rio Grande do Sul, Brazil. The Laboratório Regional de Diagnóstico of the Universidade Federal de Pelotas received 146 wandering dogs for necropsy, sent by the City Hall of Pelotas from March 2012 to January 2020. Among the necropsied animals, seventeen dogs (11.64%) were diagnosed with dioctophymosis. Among these dogs, 11 were parasitized with one specimen in the right kidney, two dogs presented two specimens in the right kidney, and in other two dogs, the parasites were in the abdominal cavity. In one dog, two parasites were found in the left kidney; in another dog, both kidneys were parasitized, with two parasites in the right kidney and one in the left kidney. The data obtained in this study showed that the occurrence of D. renale in stray dogs in the city of Pelotas is high, and D. renale mainly parasitizes the right kidney.

Dioctophyme renale: in vitro culture, production of excretory and secretory antigens, and their use in immunodiagnosis.

The nematode Dioctophyme renale affects mainly the right kidney of domestic and wild mammals, in addition to having zoonotic potential. Therefore, this study aimed to produce excretion and secretion antigens of adult D. renale (DES) to diagnose canine dioctophimosis. To obtain the excretion and secretion antigens (DES), five D. renale adults were maintained for three weeks in supplemented RPMI medium with weekly supernatant collections. After the DES concentration, 2200 mL of the collected supernatant was used, which was centrifuged, followed by two filtrations and dialyzed, resulting in 12.5 mL of DES with a protein concentration of 0.59 mg/mL. The polyacrylamide gel electrophoresis (SDS-PAGE) of the DES antigen showed fractions with molecular weights ranging from 30 to 250 Kda. In the indirect ELISA with the DES antigen, the mean absorbance of the positive sera (38) was 0.839 ± 0.267, and the mean of the negative control sera (7) was 0.208 ± 0.083; the specificity and sensitivity of the ELISA were 100 and 97.4 %, respectively, being as effective as the surgical method in the presence of viable parasites. Thus, for the first time, this study describes the production of excretion and secretion antigens of adult D. renale and standardizes an indirect ELISA to diagnose dioctophimosis.

A rare case of ectopic dioctophymosis in Leopardus pardalis (Carnivora, Felidae) in Paraguay.

An adult female Leopardus pardalis from Jardín Botánico y Zoológico de Asunción, Paraguay was brought in from the wild, and inspected for a parasitic structure attached to the vulva. The parasite was removed and was identified as a Dioctophyme renale female. Blood samples and ultrasound did not show abnormalities in any organ, confirming the ectopic presentation of the parasite. This is the first report of D. renale in the L. pardalis and a first time for ectopic location in vagina and spontaneous elimination in a felid.

Dioctophyme renale in wandering dogs in Pelotas, South of Brasil / Dioctophyme renale em cães errantes no município de Pelotas, Sul do Brasil

Abstract This study aimed to verify the occurrence of Dioctophyme renale in stray dogs in the city of Pelotas, in the state of Rio Grande do Sul, Brazil. The Laboratório Regional de Diagnóstico of the Universidade Federal de Pelotas received 146 wandering dogs for necropsy, sent by the City Hall of Pelotas from March 2012 to January 2020. Among the necropsied animals, seventeen dogs (11.64%) were diagnosed with dioctophymosis. Among these dogs, 11 were parasitized with one specimen in the right kidney, two dogs presented two specimens in the right kidney, and in other two dogs, the parasites were in the abdominal cavity. In one dog, two parasites were found in the left kidney; in another dog, both kidneys were parasitized, with two parasites in the right kidney and one in the left kidney. The data obtained in this study showed that the occurrence of D. renale in stray dogs in the city of Pelotas is high, and D. renale mainly parasitizes the right kidney.

Resumo Este trabalho possui como objetivo verificar a ocorrência de D. renale em cães errantes do município de Pelotas, no Rio Grande do Sul, Brasil. O Laboratório Regional de Diagnóstico da Universidade Federal de Pelotas recebeu 146 cães errantes para necropsia, encaminhados pela Prefeitura Municipal de Pelotas, no período de março de 2012 a janeiro de 2020. Dentre os cães necropsiados, 17 animais foram diagnosticados com dioctofimose, determinando uma ocorrência de 11,64%. Desses animais, onze estavam parasitados com um exemplar no rim direito, dois animais possuíam dois exemplares no rim direito. Em dois animais, os parasitas estavam na cavidade abdominal; em um animal havia, dois parasitas no rim esquerdo e noutro animal os dois rins estavam parasitados, tendo dois exemplares no rim direito e um exemplar no rim esquerdo. Os dados obtidos neste trabalho permitem concluir que é elevada a ocorrência de D. renale nos cães errantes do município de Pelotas, parasitando principalmente o rim direito.

Occurrence of ectopic Dioctophyma renale in a Bolivian dog.

This is the first scientific report of the ectopic occurrence of Dioctophyma renale in subcutaneous tissue of a domestic dog's paw from Bolivia. An 18-month-old male dog (Pug) from Bolivia (San Matías) was examined on September 15, 2020 presenting limited mobility and apparent swelling in the left pelvic limb. After clinic evaluation, left foot edema was observed from tibio-tarsal to metatarsophalangeal joints which was more pronounced on the dorsolateral face. An incision at the site revealed serosanguinous exudation associated with a wide reddish nematode, which was identified as a female Dioctophyma renale. Epidemiological considerations were highlighted as this disease has zoonotic potential, and the infected dog was kept in a yard to which amphibians (Anura) and reptiles had access. Moreover, there is a lack of information on its occurrence in San Matías, a border city with Brazil.

Occurrence of Dioctophyme renale (Goeze, 1782) in road-killed canids of Iran and its public health implication.

Dioctophyme renale, is the largest of parasitic nematodes, which infects different species of fish-eating carnivores worldwide. The northern provinces of Iran (Guilan and Mazandaran) located in south of the Caspian Sea are suitable for parasitic infections due to the mild and humid climatic conditions. From separate surveys of road-killed canids in various parts of the Caspian Sea littoral area in Iran, 70 carcasses were collected along the roads of Guilan and Mazandaran from 2015 to 2017. Dioctophyme renale detected by direct observation and molecular methods based on Cytochrome c oxidase subunit 1 (COX1 gene) sequencing analysis. Molecular investigation was also performed to validate prevalence and reduce false negative concerns. Dioctophyme renale was found in eight of 70 carnivores, mostly in the right kidneys, as well as two cases in the abdominal cavity of a dog and a golden jackal. More carcasses on the roads were seen with lacerated internal organs. Given the frequent number of giant kidney worms in canids in the region, the transmission of this zoonotic helminth to humans seems possible, since the area is a tourism hub in the country. The infection burden of this helminth should be investigated using DNA analysis of kidney tissue of road-killed carnivores in Iran.

Giant Red Kidney Worm (Dioctophyma renale) Screening and Treatment Protocol and Aberrant Worm Migration In Dogs From Ontario and Manitoba, Canada.

The life cycle of Dioctophyma renale involves an intermediate host (oligochaete), a paratenic hosts (fish and frogs), and a definitive host (mustelids and canids). Dogs are at risk of infection with D. renale when they consume paratenic hosts infected with the larval form of D. renale. Water containing the oligochaete intermediate host cannot be disregarded as another source of infection. Infections occur mainly in the right kidney, but worms have also been found in the abdominal cavity as well as other organs. Most dogs appear asymptomatic and infections are usually noted as incidental findings on necropsy. Recently, the Ontario Society for the Prevention of Cruelty to Animals (SPCA) and Humane Society conducted transports of dogs located in northern remote communities. In 2016, some female dogs were found to be infected with D. renale upon ovariohysterectomy. In response to this discovery, we developed a screening protocol to screen for D. renale infections. In 2018, a total of 130 intact dogs were transferred from 2 northern communities in the provinces of Ontario and Manitoba. A prevalence of 7.94% (95% confidence interval 3.87-14.11%) was found from dogs from the northern communities. The screening protocol we developed provides a method of screening for dogs that are transported from communities that could be at risk of infection with D. renale.

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.

Urinary capillariasis: Case report of Pearsonema (syn. Capillaria) plica infection in a dog in Greece.

Pearsonema (syn. Capillaria) plica is a nematode that resides in the urinary bladder of canids, felids and mustelids (definitive hosts) and is classified in the same class as Trichuris spp. Epidemiological and clinical data on Pearsonema plica infection in domestic animals are limited. The nematode has an indirect lifecycle that involves earthworms as intermediate hosts. A six-year-old crossbred dog from Greece, presented a history of intermittent pollakiuria and hematuria. At urine analysis, P. plica eggs were found in the urine sediment. The dog was successfully treated with a double dose of milbemycin. To the best of our knowledge this is the first case of urinary capillariasis diagnosed in a domestic animal in Greece.

Efficacy of milbemycin oxime/afoxolaner chewable tablets (NEXGARD SPECTRA®) against Capillaria aerophila and Capillaria boehmi in naturally infected dogs.

BACKGROUND: Capillaria aerophila and Capillaria boehmi parasitize the respiratory system of wild and domestic carnivores. Capillaria aerophila inhabits the trachea and bronchi of dogs and cats, while C. boehmi affects the nasal cavities and sinuses of dogs. In dogs the infection may be subclinical or characterized by varying respiratory distress. METHODS: The present study evaluated the efficacy of an oral formulation containing milbemycin oxime and afoxolaner (NEXGARD SPECTRA®) in dogs naturally infected with C. aerophila and/or C. boehmi from three enzootic areas of Italy. Dogs were enrolled pending fecal examination and molecular confirmation of respiratory capillarioses. Dogs were allocated in two groups: Group 1 (G1, 25 dogs), treated with a negative control product with no anthelmintic activity (afoxolaner, NEXGARD®), and Group 2 (G2, 26 dogs), treated with NEXGARD SPECTRA®. At the day of treatment administration (Day 0), all dogs were clinically examined. Dogs were again subjected to clinical and fecal examinations at Days 28 (± 4) and 56 (± 2). The primary criterion for treatment efficacy was the reduction of fecal Capillaria egg counts in G2 compared with G1. The regression of/recovery from baseline clinical signs was considered as a further efficacy criterion. RESULTS: Percentage reduction of fecal Capillaria egg counts in the NEXGARD SPECTRA® group compared to the control group was > 97% on Day 28 and 100% on Day 56, respectively (p < 0.05 for both time points). Twelve of the 13 dogs in the NEXGARD SPECTRA® group with respiratory signs prior to treatment were free of clinical signs at the end of the study. Conversely, the six control group dogs with respiratory signs prior to treatment remained symptomatic. CONCLUSIONS: Results of the present study showed that NEXGARD SPECTRA® was safe and highly efficacious in the reduction of C. aerophila and C. boehmi eggs after one treatment with a complete reduction of the egg output after the second administration associated with a recovery from respiratory signs.

Helminth infracommunity in a maned wolf, Chrysocyon brachyurus, from the humid Chaco, Argentina.

Parasitism is an important factor in conservation worldwide, especially for endangered species, as it can affect host populations by reducing growth rates, fecundity and affecting nutritional status. The maned wolf Chrysocyon brachyurus, a near-threatened species, is distributed across different habitats from the south Amazonian forest in Brazil to northern Argentina, Paraguay and eastern Bolivia. Most studies on gastrointestinal parasites in wild maned wolves are based on coprological findings, and there is little information about adult parasites and parasite species richness. Therefore, this study aims to expand the knowledge about the helminth infracommunity of a maned wolf, describe adult parasites, and explore parasitic coinfections. We performed a necropsy of an adult individual found road killed in Chaco province, Argentina. We collected adult worms from subcutaneous tissues, from the right ventricle, kidneys, and intestine. The parasites were morphologically identified as Dirofilaria immitis, Dioctophyma renale and Spirometra sp. respectively. To our knowledge, this is the first record for adults of Dirofilaria immitis in maned wolves. Filarioids were located within the heart as well as in subcutaneous tissues with mature females containing uterine microfilariae; this study also adds C. brachyurus as a new host for Spirometra sp. in Argentina. Considering that the three helminths found herein are zoonotic and that the maned wolf is an endangered canid, it is essential provide baseline information to determine the risk factors involved in the transmission and extend the studies to sympatric wild and domestic canids in the area.