[Iso-osmotic regulation in cestodes from freshwater fishes]

The content of sodium, potassium, calcium, and magnesium ions was determined in cestodes Ligula intestinalis, Eubothrium rugosum, and Triaenophorus nodulosus. In freshwater fishes the total concentration of Na, K, Ca, Mg ions in cestode tissue water is practically similar to that of fishes muscles and in serum. It was suggested that examined cestodes have isoosmotic regulation of the water-salt balance.