Osmotic and Ionic Changes in Blood and Muscle of Migrating Salmonids

• Main Author: PARRY, GWYNETH
• Format: Text
• Language: English
• Published: Company of Biologists 1961
• Subjects: Articles; Atlantic salmon
• Online Access: http://jeb.biologists.org/cgi/content/short/38/2/411

1. Osmoregulation of the Atlantic salmon in fresh water and sea water, and during transfers from one salinity to another, has been studied by measuring the freezingpoint and the levels of some inorganic ions in the blood plasma, and water content and ions in whole muscle. 2. An increase in blood concentration of about 12% follows the transfer of juvenile fish (smolts) from fresh water to sea water; and a fall of concentration of about 5% follows the transfer of the adult fish from sea water to fresh water. 3. Some changes in analyses of whole muscle indicate changes in the extracellular compartment during transfers from one salinity to another. 4. Osmoregulatory powers of juvenile salmon (smolts) and fresh-run adults are good, but spent fish (kelts) returning from fresh water to sea water, osmoregulate with difficulty or not at all.