Growth rate, body composition, and intake of either dry matter or energy did not differ significantly (P > 0.05) between two groups of juvenile brown trout (Salmo trutta) fed either a low- or high-moisture semipurified diet at different rates to compensate for a diet energy density gradient. Feed/gain efficiency, on an as-fed basis, was significantly greater (P < 0.01) in fish fed the low-moisture diet, but did not differ (P > 0.05) when compared on the basis of dry matter or energy intake.