Abstract:A digestive experiment was conducted on Japanese sea bass Lateolabrax japonicus weighing 30±2.3g at 23±2℃. Chromic oxide (Cr2O3) was used as the inert indicator. The apparent digestibility of dry matter, protein, lipid, energy, and amino acids in seven feed ingredients (white meal, blood meal, shrimp meal, feather meal, double low rapeseed meal, high gluten flour, and rice bran) were determined. The test diets were composed of 70% reference diet and 30% test ingredient. The results showed that the apparent digestibility of dry matter was in the range of 98.71%~41.84%, among which the fish meal (98.71%) was the highest compared to the others. Digestible protein from these ingredients was in the range of 45.01%~86.86%,comparatively, above 98% for fish meal and rice bran. The assimilation of energy was the highest in the fish meal (95.24%) and the lowest in the shrimp meal (65.54%). The liver histology has been affected by the diets containing blood meal, feather meal, double low rapeseed meal, high gluten flour, and rice bran after 70 days experiment. The lesions occurred, including fatty degeneration and leukocyte of infiltration in the hepatic tissue, and aquatic degeneration, etc. With blood meal, feather meal, and double low rapeseed meal replacements, pathological disruption of intestine was observed, characterized by sloughing of epithelium cell and increasing amounts of leukocytes in it.
