Abstract
Yearling hatchery-reared brook charr, Salvelinus fontinalis Mitchill, were trained during a 20-day period at different water velocities: 0.00, 0.85, 1.72, and 2.50 body lengths/s (bl/s). Our results indicate that growth (wet weight), food conversion efficiency, and the deposition of lipids on the digestive tract were maximized at 0.85 bl/s. The individual growth (wet weight) was also more homogeneous at this water speed. The storage of lipids in the white muscles was significantly lower in still water (0.00 bl/s) while the increase in length, the increase in the dry weight of the carcass (whole fish less internal organs), and the relative water content of the muscle showed no significant differences between the tested water velocities. Behavioural observations indicated that the frequency of agonistic behaviours between individuals was important in still water, but decreased significantly in the presence of a water current.