The influence of the amylopectin/amylose ratio in samples of corn on the true metabolizable energy value for ducks

The present study was conducted to investigate the relationship between amylopectin (AP), amylose (AM) content and AP/AM ratio of corns and true metabolizable energy (TME) value for ducks, and further to establish the prediction equations to estimate the TME value of corns. Six representative samples were selected from 21 corn samples based on the AP/AM ratio. According to the modified Sibbald's method, male Cherry Valley ducks were then used to assay the TME values. Stepwise regression analysis was performed to establish the prediction equations of TME values using dry matter (DM), crude protein (CP), ether extract (EE), ash, crude fiber (CF), acid detergent fiber (ADF), neutral detergent fiber (NDF), AM, AP, AP/AM and gross energy (GE) as independent variables. Correlation analysis exhibited a significant positive correlation of AP ( r = 0.84, P