Measurement of gastrointestinal passage rate in Atlantic salmon (Salmo salar) fed dry or soaked feed

Individual variation in the gastrointestinal passage rate was large and few significant differences were revealed. However, soaked feed gave a significantly higher gastric evacuation rate than dry feed shortly (2 h) after feeding. As the fish regurgitated some pellets, the method may be most suitable when feeding small rations. Besides, due to variation a larger number of replicates would increase the power of the test.