Pathogenicity and Characterization of Microsporidiosis in Epinephelus Aeneus (Geoffroy St. Hilaire, 1817) from Parangipettai Coastal Water, Southeast Coast of India

• Vasanthan Koothan ^[1] ; Savva Sravani ^[1] ; Ayyaru Gopalakrishnan ^[1] ; M.P. Arulmoorthy ^[2]
  1. [1] Annamalai University

     Annamalai University

     India

     
  2. [2] Saveetha University

     Saveetha University

     India

     
• Localización: Thalassas: An international journal of marine sciences, ISSN 0212-5919, Vol. 41, Nº. 4, 2025
• Idioma: inglés
• Texto completo no disponible (Saber más ...)
• Resumen

  • A microsporidian infection was identified in Epinephelus aeneus specimens collected from the Parangipettai Landing Station, southeast coast of India. Among twelve individuals examined, one exhibited gross sign of infection, including muscle opacity and emaciation. Histopathological, ultrastructural, and molecular analyses were conducted to characterize the causative agent. Light microscopy revealed numerous ellipsoidal microsporidian spores within sporophorous vesicles. Histological sections showed extensive xenoma development primarily in the pyloric caeca and stomach, with marked tissue degeneration and dense spore infiltration. Scanning and transmission electron microscopy confirmed ultrastructural features typical of microsporidia, including polar filaments, sporophorous vesicles, and multilayered spore walls. A partial 791 bp fragment of the SSU rDNA gene was amplified and sequenced, and subsequent BLAST analysis indicated high similarity to Glugea eda. Phylogenetic analysis using the Neighbor-Joining method positioned the isolate (designated Glugea eda AGK; GenBank accession no. PV875338) within the family Glugeidae, closely clustering with other Glugea spp. The study provides the first confirmed record of Glugea eda-like infection in E. aeneus from Indian water, contributing into microsporidian biodiversity and host-pathogen interactions in marine ecosystems