Enterospora nucleophila
This article may be too technical for most readers to understand.(March 2020) |
Enterospora nucleophila | |
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Transmission electron micrograph of an Enterospora nucleophila-infected rodlet cell harbouring spores within its nucleus (N). No stages are visible in the cytoplasm (C)
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Scientific classification | |
Domain: | Eukaryota |
Phylum: | Microsporidia |
Class: | incertae sedis |
Genus: | Enterospora |
Species: | E. nucleophila
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Binomial name | |
Enterospora nucleophila Palenzuela, Redondo, Cali, Takvorian, Alonso-Naveiro, Alvarez-Pellitero & Sitjà-Bobadilla, 2014
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Enterospora nucleophila is a
Taxonomy
E. nucleophila is a microsporidian, a group of intracellular parasites related to
Life cycle
Only the development within gilthead sea bream is currently known.
Pathology and clinical signs
Infections by E. nucleophila are associated with stunted growth of gilthead sea bream
Impact
The disease was first noticed in the early 2000s. However, the difficulties in the diagnosis of the parasite probably delayed acknowledgement of its presence and impact. Indeed, the parasite and its association with gilthead sea bream emaciative microsporidiosis were not described until recently, but retrospective studies identified it in samples taken in 1993.[1] The main clinical signs are only noticed in severe infections and can be largely masked by other infectious diseases of gilthead sea bream. Therefore, the approaches to understand the true impact of the disease can only be formed after the development of appropriate diagnostic methods to conduct specific epidemiological and risk-assessment studies. Besides the mortality, the main economic impact of the parasite is related to the segregation of sizes caused by the infection within affected sea cages, as it results in inefficient feeding, serious biomass and quality losses at the harvest.
Diagnosis
Presumptive diagnosis can be made based on clinical signs and histopathological examination of the intestinal epithelium. The most common observation in heavy infections is the presence of numerous hypertrophied cell nuclei and a remarkable hypercellularity.[1] When present, tiny microsporidian spores (1.67 x 1.05 µm) can be identified. Like in other microsporidioses, the detection of spores can be facilitated with calcofluor-white M2R or luna stains.[4] More reliable confirmatory diagnosis of E. nucleophila is possible with molecular-based methods, in situ hybridization[5] and RT-PCR tests.[6]
Treatments
There are currently no approved therapies for E. nucleophila. Microsporidian infections relevant for human and animal medicine are normally treated with Albendazole, Metronidazole or Fumagillin, but the use of these drugs in aquaculture settings is not regulated and their effectivity for treating gilthead sea bream microsporidiosis is unknown.
Research
As an emerging disease of gilthead sea bream, understanding E. nucleophila infection and exploring ways to mitigate its impact in
References
- ^ a b c d e f Palenzuela, O., Redondo, M. J., Cali, A., Takvorian, P. M., Alonso-Naveiro, M., Alvarez-Pellitero, P., & Sitja-Bobadilla, A. (2014). A new intranuclear microsporidium, Enterospora nucleophila n. sp., causing an emaciative syndrome in a piscine host (Sparus aurata), prompts the redescription of the family Enterocytozoonidae. Int. J. Parasitol. 44:189-203.http://doi.org/10.1016/j.ijpara.2013.10.005
- ^ Vossbrinck, C.R., & Debrunner-Vossbrinck, B.A. (2005). Molecular phylogeny of the Microsporidia: ecological, ultrastructural and taxonomic considerations. Folia Parasitol. 52:131-142.
- ^ Amparo Picard-Sánchez, M. Carla Piazzon, Nahla Hossameldin Ahmed, Raquel Del Pozo, Ariadna Sitjà-Bobadilla, Oswaldo Palenzuela. 2020. Pathology and cellular immune response of gilthead sea bream (Sparus aurata) infected by Enterospora nucleophila (Microsporidia). Vet. Pathol.
- ^
- Kent, M.; Harper, C.; Wolf, J. (2012). "Documented and Potential Research Impacts of Subclinical Diseases in Zebrafish". NIHMSID: NIHMS488220. Institute for Laboratory Animal Research.
- This review cites this research.
- Peterson, T.; Spitsbergen, J.; Feist, S.; Kent, M. (2011). "Luna stain, an improved selective stain for detection of microsporidian spores in histologic sections". Diseases of Aquatic Organisms (DAO). 95 (2). NIHMSID: NIHMS588204.
- Kent, M.; Harper, C.; Wolf, J. (2012). "Documented and Potential Research Impacts of Subclinical Diseases in Zebrafish".
- ^ Ahmed N.H., Caffara, M., Sitjà-Bobadilla, A., Fioravanti, M.L., Mazzone, A., Aboulezz, A. S., Metwally, A.M., Omar M.A., Palenzuela, O. (2019). Detection of the intranuclear microsporidian Enterospora nucleophila in gilthead sea bream by In situ Hybridization. J. Fish Dis. 42: 809-815. https://doi.org/10.1111/jfd.12993
- ^ Hossam Eldin N, Abu El Ezz A, Del Pozo R, Metwally A, Omar M, Sitjà-Bobadilla A, Palenzuela O (2017) Validation of diagnostic methods for the detection of Enterospora nucleophila (Microsporidia) in the intestine of gilthead sea bream. Proceedings of the 18th Int. Conference on Diseases of Fish & Shellfish, p.410. (192-P).
- ^ "ParaFishControl Project".