Ciliate Uronema marinum is the causative agent of scuticociliatosis in farm raised turbot Scophthalmus maximus

  • Guangxun Du
  • Lingyun QuEmail author
  • Kun Shang
  • Chengjun Sun
  • Chen Wang
  • Ping Gao


To identify the pathogen that causes scuticociliatosis in farmed-raised turbot Scophthalmus maximus, we isolated a ciliate from the brain tissue of an infected turbot and identified it as Uronema marinum based on morphological and molecular evidence. We then infected the turbots in artificial laboratory settings with pure cultured U. marinum. The infected turbots showed syndromes similar to those observed in naturally infected ones. Furthermore, microscopic examination and PCR detection confirmed the presence of the ciliate in the tissues of those laboratory-infected turbots. To our best knowledge, this is the first report of scuticociliatosis caused by U. marinum in farm-raised turbot S. maximus in China.


Scophthalmus maximus scuticociliatosis histopathology Uronema marinum 


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The LZLP2013 is morphologically identified by Prof. HU Xiaozhong and Dr. LIU Mingjian from the Laboratory of Protozoa, Ocean University of China.


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Copyright information

© Chinese Society for Oceanology and Limnology, Science Press and Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  • Guangxun Du
    • 1
  • Lingyun Qu
    • 1
    • 2
    Email author
  • Kun Shang
    • 1
    • 3
  • Chengjun Sun
    • 1
  • Chen Wang
    • 1
  • Ping Gao
    • 1
  1. 1.First Institute of OceanographyMinistry of Natural Resources (MNR)QingdaoChina
  2. 2.Laboratory for Marine Fisheries Science and Food Production ProcessesQingdao National Laboratory for Marine Science and TechnologyQingdaoChina
  3. 3.College of Fisheries and Life ScienceDalian Ocean UniversityDalianChina

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