The Effect of Temperature on the Rate of Gastric Evacuation in Brook Trout Salvelinus fontinalis Fed on Commercial Pellets: Group-Feeding

The gastric evacuation rates (GER) of brook trout Salvelinus fontinalis were determined under three temperatures: 12, 15, and 20 C. A group of brook trout (ranging from 72-80 g) were fed on commercial pellets to apparent satiation and by means of serial slaughter their stomach contents were sampled with 3 h intervals until the first empty stomach was observed. The square-root model adequately described the gastric evacuation of brook trout by the current stomach content mass. The GER increased exponentially with temperature: dS(t)/dt = -0.0194e(0.028T) (g h(-1)), r(2)= 0.91, where T is temperature in C. The effect of temperature on GER of brook trout was comparatively lower than other Salmonid species.