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Helgoland Marine Research

Open Access

Histology of pseudobranchial tumours in Atlantic cod(Gadus morhua) from the North Sea and the Baltic Sea

  • B. Watermann1, 2 and
  • V. Dethlefsen1
Helgoländer Meeresuntersuchungen35:BF01997554


Atlantic cod bearing pseudobranchial tumours were investigated from both North Sea and Baltic Sea areas. Light and electron microscopic studies revealed a tumorous structure previously described in cod from Atlantic and Pacific waters. Additionally, cysts, multinucleated cells and early stages of mitosis are described. These findings support the hypothesis that pseudobranchial tumours are instigated by a protozoan infection causing xenotumours associated with the pseudobranch organ. The cells contained in these lesions showed similarities to amoebae.


Waste WaterWater ManagementWater PollutionMicroscopic StudyElectron Microscopic Study