HATCHERY-REARED LANDLOCKED ARCTIC CHARR, SALVELINUS-ALPINUS (L), FROM LAKE TAKVATN REARED IN FRESH AND SEA-WATER .2. THE EFFECT OF SALINITY ON THE DIGESTIBILITY OF PROTEIN, LIPID AND INDIVIDUAL FATTY-ACIDS IN A CAPELIN ROE DIET AND COMMERCIAL FEED

Hatchery-reared landlocked Arctic charr, Salvelinus alpinus (L.), from Lake Takvatn were fed either a commercial feed or a capelin roe diet in fresh and sea water at 8-degrees-C. The apparent digestibility of lipid and protein in the capelin roe diet was 98 and 92%, respectively. The digestibility of lipid and protein in the commercial feed was approximately 90%, when fed to fish held in fresh water. Reduced digestibility coefficients for protein, lipid and some of the dietary fatty acids were detected when the diets were fed to fish reared in sea water.