Gas exchange and control of breathing in the electric eel, Electrophorus electricus

@article{Johansen2004GasEA,
  title={Gas exchange and control of breathing in the electric eel, Electrophorus electricus},
  author={Kjell Johansen and Claude J. M. Lenfant and Knut Schmidt-Nielsen and Jorge A. Petersen},
  journal={Zeitschrift f{\"u}r vergleichende Physiologie},
  year={2004},
  volume={61},
  pages={137-163}
}
Summary1.The electric eel Electrophorus electricus is an obligate air breather. Its mouth is structurally adapted for air breathing by an extensively diverticulated and richly vascularized oral mucosa. Air is regularly taken into the mouth and later expelled at the opercular openings. The present investigation concerns the respiratory properties of blood, the dynamics of gas exchange and the control of breathing in the electric eel.2.Fishes were anesthetized and catheters implanted for sampling… 

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TLDR
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