Case reportEnteromyxum leei (Myxozoa), a Lethal Intruder of Tropical Pet Fish: First Case in Humphead Wrasse, Cheilinus undulatus (Rüppell, 1835)
Section snippets
Case History
A humphead wrasse (23 cm, 161 g) arrived at the facilities of the Cretaquarium, the public aquarium of the Hellenic Centre for Marine Research located in Gournes, Crete, Greece. The fish remained alone in a flow-through tank in the quarantine facilities for 11 days before being transferred to the exhibition tank where it died 9 days later. While quarantined, the behavior of the wrasse was monitored on a daily basis. No fecal, skin, or gill examinations were performed. The day before the
Laboratory Evaluation
After the wrasse died a necropsy was performed using standard microbiological, parasitological, and histological procedures. Direct streaking from head and trunk kidney on tryptic soy agar and thiosulfate citrate bile sucrose was performed. Fresh smears from several tissues were made and examined under light microscopy. Staining of dried smears was performed using Giemsa and methylene blue/azure II/basic fuchsin. Tissue samples from spleen, kidney, liver, heart, and intestine were fixed in
Diagnosis
There were no obvious external pathological abnormalities and no gross lesions found on or within the epidermis, gills, or fins. Internally, no ascites or hemorrhage was apparent in major organs (e.g., liver, heart, kidney, spleen) and bacterial cultures were negative for growth on both media types. The parasitological examination of fresh skin, gills, bile, liver and kidney smears/imprints was negative. The intestinal tract showed evidence of a mass infection of a myxozoan resembling the
Discussion
Enteromyxum leei has been previously reported as causing mortalities in L'Aquarium Barcelona, affecting more than 25 fish species; its occurrence was confined to the Mediterranean section.14 However, possible transmission of E. leei to tropical fish should be expected because the pathogen has become established in the tropical marine region of the Red Sea via imported fish culture stocks.17 Moreover, in the early 1980s, Kent identified a myxozoan resembling E. leei in a dying anemone fish,
Acknowledgments
We thank Maria Papadaki for technical assistance in histology and the aquariologists of Cretaquarium.
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2021, Comparative Biochemistry and Physiology -Part A : Molecular and Integrative PhysiologyCitation Excerpt :The inflammatory morphological changes observed were likely caused by the parasitic organisms. The mucosal surface-attached parasite, probably Enteromyxum leei, a species of the myxozoan parasites (Cuadrado et al., 2007), are known to affect wrasses and considered quite significant in Mediterranean aquaculture (Katharios et al., 2011). In addition, a common feature observed in the current fish as well as in cultured Ballan wrasse (Le et al., 2019) was the strong presence of the eosinophilic granular cells (EGC).
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2015, Fish and Shellfish ImmunologyCitation Excerpt :Similar findings of an increase in granulocytes in submucosa were reported in intestines of cestode-infected rainbow trout [15,49], and tench infected with a cestode [50]. Recruitment of the MCs into intestine of fish infected with myxozoan parasite Enteromyxum leei have been reported in several records [51–56] and the same phenomenon was reported for other parasitic diseases (see review by Alvarez-Pellitero [57]). In the current study of the chub-acanthocephalan system within the intestinal epithelium, a close association or contact between RCs, neutrophils and MCs with mucous cells was documented.
Enteromyxum leei infection in parrotfish, Sparisoma cretense: Histopathological, morphological and molecular study
2014, Veterinary ParasitologyCitation Excerpt :The economic consequences of the disease are extremely high since they comprise the cost of morbidity e.g. loss of feeds, reduced growth rates, susceptibility to secondary infection, followed by the cost of mortality e.g. loss of biomass. The host range of the parasite is one of the largest for myxosporean parasites with more than 40 species reported susceptible (Katharios et al., 2011; Sitja-Bobadilla and Palenzuela, 2012). The original host of the parasite is unknown and the fact that there are only few records of the parasite in wild populations mostly living in proximity with enzootic marine fish farms (Diamant et al., 2006) complicates further the problem of identifying the initial source making it a “chicken and egg situation”.
A fish kill at the Aposelemis dam (Crete, Greece) caused by heavy parasitism by Ichthyobodo sp.
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