Effect of dietary charcoal and wood vinegar mixture (CV82) on body composition of olive flounder Paralichthys olivaceus

The effects of dietary charcoal and wood vinegar mixture (CV82) were determined on growth, body composition, and vitality of olive flounder Paralichthys ofivaceus. Five experimental diets were formulated to contain 0% (control), 0.5%, 1.0%, 1.5%, and 2.0% CV82. Weight gain was lowest in the control diet group (47.7 g) and highest in the 1.0% CV82 group (53.0 g). Feed efficiency was lowest in the control diet group (87.3%) but significantly higher in the 0.5% CV82 diet group (95.8%), (P < 0.05). The condition factor and hepatosomatic index were not affected by the dietary level of CV82. Moisture and crude protein content did not significantly differ among the treatments. However, crude lipid was lower in the 1.0% and 1.5% CV82 diet groups of 3.4% and 3.5%, respectively. Serum glutamic oxaloacetic acid and glutamic pyruvic transaminase activities decreased significantly with increasing dietary CV82 level. Therefore, these results suggested that the suitable dietary CV82 level could be between 0.5%, and 1.0% in olive flounder for the maximum weight gain, feed efficiency, and vitality.