Development of practical diet for aquaculture of Japanese flounder
Feeding experiments were conducted to examine the potential use of defatted soybean meal (SBM) in combinations with blood meal (BM), corn gluten meal (CGM) and freeze dried meat of blue mussel (BMM) as a partial replacement of fish meal (FM) in the diet of Japanese flounder. Availability of CGM in combinations with BM and/or BMM was also examined. Juvenile fish of about 4 g in initial body weight were fed diets to satiation twice daily, 6 days per week for 8 weeks at 20℃ in both feeding experiments. Weight gain of fish fed diet replacing 45% FM protein with SBM was not different from that of fish fed the control diet containing FM as a protein source, however, feed efficiency (FE) in fish fed the SBM diet was significantly lower. Growth and feed performance of fish fed diet replacing 45% FM protein with SBM and BM were comparable to those of fish the control diet. Inclusion of 5% BMM for equal amount of SBM in the SBM-BM diet improved the growth and FE of the flounder remarkably and both values were significantly higher than those in the control. Replacing 55% of FM protein with SBM and CGM or SBM and BM resulted in poor growth performance. There were not marked differences in hematological characteristics together with proximate composition of the whole body of cultured fish fed the dietary treatments. Weight gain and FE of fish fed diet replacing 40% FM protein with CGM were inferior to those of fish fed the control diet containing FM as a protein source. Replacement of 40% FM protein with CGM and BM made those parameters worse. Inclusion of BMM in CGM-BM diet did not improve the growth of fish. Adverse effects of replacing FM protein with CGM and/or CGM and BM were stronger with increasing replacement level.These results indicate that SBM is highly available as alternative protein source for fish meal in the diet of Japanese flounder. SBM in combination with BM successfully replace about 45% of FM protein in the diet without supplemental amino acids. Furthermore, it is suggested that more replacement can be attained with inclusion of 5% BMM in the SBM diet. CGM is not considered to be useful ingredient on practical bases.
|脱脂大豆||Defatted soybean meal|
|コーングルテンミール||Corn gluten meal|