JOURNAL OF FISH BIOLOGY, cilt.89, sa.2, ss.1227-1238, 2016 (SCI-Expanded)
Gastric evacuation ( GE) experiments were performed on brook trout Salvelinus fontinalis fed commercial food pellets. The experiments included small fish ( 36 g; 15 cm total length, L-T) fed meals of 0.2, 0.4 and 0.8 g and large fish ( 152 g; 23 cm) fed meals of 0.8, 2.0 and 4.0 g at temperatures ranging from 15.1 to 18.2 degrees C. The stomach contents were thereafter sampled and weighed at 3 h intervals until the first empty stomach was observed. The course of GE was examined by use of a general power function of the data that revealed that the square-root function described the GE rate ( GER) by the current stomach content mass independently of original meal size. Using the square-root function, the relationship between GER and fish size was described by a power function of fish length, whereas the effect of temperature was described by a simple exponential function. GER of the commercial pellets fed to S. fontinalis could thus be described by dS(t)/dt = -0.000464L(1.31)e(0.052T) root S-t (g h(-1)), where S-t is stomach mass ( g) at time t ( h), L is total fish length ( cm) and T is temperature (degrees C). The result of this study should provide a useful tool for planning of feeding regimes in production of S. fontinalis by optimizing growth and minimizing food waste. (C) 2016 The Fisheries Society of the British Isles