Growth, Body Composition, and Organoleptic Evaluation of Channel Catfish Fed Diets Containing Different Percentages of Distillers' Grains with Solubles
Juvenile channel catfish (Ictalurus punctatus) were stocked in twelve 1.25-m3 floating cages at densities of 320 fish/m3 and fed to satiety twice daily for 110 d with one of four diets. Each diet contained a certain percentage (0, 10, 20, or 30%) of distillers' grains with solubles (DGS), which partially replaced soybean meal and corn. Individual weights of fish, survival, food conversion (FC, weight of feed given!weight gain by fish), and body composition (percentage moisture, protein, fat, and ash) of waste (head, skin, and viscera) and dressed carcasses were not significantly different (P > 0.05) among treatments. Fish fed a diet containing 10% DGS (mean individual total length, 26.7 cm) were significantly shorter (P < 0.05) than fish fed a diet containing 30% DGS (27.6 cm), but they were not significantly different in length (P > 0.05) from fish fed diets with 0 and 20% DGS. Average individual weight was 219 g, survival was 92.1%, and FC was 1.6. Percentage fat (dry-matter basis) in the carcasses of cage-reared channel catfish averaged 38%. Organoleptic evaluation of fillets indicated that the fat complex flavor was of significantly higher intensity (P < 0.05) in cage-reared fish than in pond-raised fish. However, organoleptic evaluation indicated that DGS impart no adverse taste to channel catfish. These data indicate that DGS can be used in a least-cost diet formulation for channel catfish at rates of up to 30%. This option allows feed producers flexibility in diet formulations for commercial catfish diets.