Apparent digestibility coefficients of selected feed ingredients for Japanese sea bass (Lateolabrax japonicus) reared in sea water

Apparent digestibility coefficients (ADC) of seven selected feed ingredients, pet-food poultry by-product meal (P-BMB), feed-grade poultry by-product meal (F-PBM), blood meal (BM), feather meal (FEM), soybean meal (SBM), rapeseed meal (RSM), silkworm pupa (SWP) and a blend (MM) of P-PBM, F-PBM, BM and FEM, for Japanese sea bass, Lateolabrax japonicus, were measured. A reference diet was formulated to contain 42.0 % crude protein and 18.9 MJ/kg gross energy, and eight test diets were formulated by combining the reference diet and each of the tested ingredients at a ratio of 70∶30. Chromic oxide was added at 1% in the reference diet and test diets as inert marker. During the experiment, the fish were fed the reference diet and test diets twice daily, and fecal sample was collected by siphon two hours after each feeding. Results of the experiment showed dry matter ADC of the tested ingredients ranged within 61%-87%, and protein ADC within 80%-96%, and energy ADC within 75%-93%. ADC of protein of SBM was the highest, and ADC of dry matter and energy of BM was the highest, among the tested ingredients. ADC of protein of MM was the lowest, while ADC of dry matter and energy of RSM was the lowest among the tested ingredients.