Abstract:
A digestive experiment was conducted on Japanese sea bass (Lateolabrax japonicus) weighing 30±1.80g at 25±1℃. Chromic oxide(Cr 2O 3) was used as the inert indicator and apparent digestibility of dry matter, protein, lipid, energy and amino acids in various feed ingredients were determined. The test diets were composed of 70% reference diet and 30% test ingredient. Apparent digestibility of dry matter of fish meal, soybean meal and peanut meal was higher than 60%. Japanese sea bass had high digestibility of fat and protein in fish meal, soybean meal,peanut meal and rapeseed meal (more than 80%). The highest digestibility of energy appeared in fish meal (83.96%) and the lowest digestibility appeared in cotton seed meal(16.99%). Apparent digestibility coefficients of 16 amino acids in each test ingredient were determined and they showed similar trend to protein digestibility. Amino acid availability values, except for histidine, methionine and valine,in meat and bone meal for fish were lower than those in other test ingredients. Oilseed meal showed lower availability for sulphur amino acids (e.g., methionine) than that for other amino acids. Histidine availability values was lowest in fish meal while threonine availability values was lowest in meat and bone meal.