APPARENT DIGESTIBILITY COEFFICIENT OF CRUDE PROTEIN AND ENERGY FOR SIX COMMERCIAL FEED INGREDIENTS FOR CHINESE LONG-SNOUT CATFISH

Using the chromic oxide (Cr2O3) as an indicator, the apparent digestibility coefficients of crude protein and energy for fish meal, blood meal, soybean meal, rape cake meal, wheat meal and corn protein meal were determined for one-year old Chinese long-snout catfish (Leiocassis longirostris Gunther). The tested diet was a pelleted mixture of 70% referentce diet and 30% feed ingredient. The fecal samples were collected by using the siphon technique. The apparent digestibility coefficients of reference diet and test diets were reduced by 10%. The digestibility determined by this method is in more agreetment with the fish digestion physioloy as compared to the other methods used. The apparent digestibility coefficients of six ingredients are discussed in this paper.