THE DIGESTIBILITY OF NUTRIENT SOURCES FOR COMMON CARP, CYPRINUS-CARPIO LINNAEUS

The apparent digestibility of protein, fats, carbohydrate and energy w ithin three feed ingredients (wheat, barley and corn) for common carp, Cyprinus carpio Linnaeus, was studied, using chromic oxide as a dieta ry marker. Each experimental diet consisted of a mixture of the test i ngredient and 50% basal diet (containing 50% soybean meal, 35% wheat m eal, 10% soybean oil, plus 5% vitamins, egg yolk, guar and chromic oxi de). It was found that in wheat meal the protein had an apparent diges tibility of 92%, and the lipid an apparent digestibility of 80%. The a pparent digestibility of corn was 81% for protein and 90% for lipid, w hile for barley the figures were 73% and 67%, respectively. For appare nt digestible energy, the figures were 12.39 kJ g(-1) for wheat, 6.69 kJ g(-1)for barley and 9.32 kJ g(-1) for corn.