Effects of Dietary Bamboo Charcoal on Growth Parameters, Apparent Digestibility and Ammonia Nitrogen Excretion of Tiger Puffer Fish, Takifugu rubripes

摘要

A-50 day feeding trial was carried out to determine effects of dietary bamboo charcoal (BC) on growth, nutrient utilization and ammonia nitrogen excretion of tiger puffer fish, Takifugu rubripes. Six levels of BC (0, 0.004, 0.01, 0.1, 1 and 4%) were supplemented to the basal diet and fed to fish (initial BW, 53 ± 2 g) at 3% of body weight. At the end of the trial, body weight gain and specific growth rate of fish fed the diet supplemented with 4% BC were significantly higher than the other groups. Furthermore, 4% BC group showed significantly higher feed intake and feed efficiency and protein efficiency ratios than those of fish fed diet supplemented with 0% BC diet (control) group. In nutrient and dry matter digestibility of fish fed 4% BC diet was significantly higher than those fed 0 and 0.004% BC diets. Moreover, protein digestibilities of fish fed diets including 0.01% - 4% BC diets were significantly higher than that of fish fed 0.004% BC and control diets. After termination of the rearing trial, ammonia nitrogen excretion rates were determined with fish of (BW 130 ±2 g). Fish fed 4% BC diet was significantly lower excretion rate than those fed 0.004% BC and control diets. These results indicated that diet with 4% BC improved the growth and nutrient utilization of juvenile tiger puffer under the conditions employed in this study.