Metabolizability and Nutritional Implications of L-Arabinose and D-Xylose for Chicks

Abstract

Inclusion of 40% L-arabinose and D-xylose in chicks' diet resulted in a severe depression of growth, feed efficiency, liver and gastrointestinal sizes and depletion in liver and muscle glycogen. Twenty per cent xylose also depressed growth significantly. From 3 experiments the average metabolizable energy values for arabinose and xylose at 20% dietary level were 3.06 and 2.54 kcal/g of pentose, respectively. The effects of graded dietary levels (10, 20 and 40%) of arabinose and xylose were compared. The data indicated that plasma uric acid was elevated at the two higher levels of each pentose. Plasma cholesterol was significantly higher among birds receiving a 40% xylose diet. Total reducing sugars in blood plasma were consistently higher for each level of arabinose, whereas xylose treatment at each level significantly increased the total reducing sugars in the plasma. Liver and muscle glycogen was proportionally depleted with increase in dietary pentose level. Glycogen in liver was more depleted among birds receiving 40% arabinose as compared with those fed the same level of xylose.