The absorption of dietary L-lysine and extruded L-lysine in pigs

Abstract

Two experiments were conducted to study the absorption of synthetic L-lysine and of heat-treated lysine in growing pigs. In the first experiment, three cross-bred pigs were fed on a control diet (6.9 g lysine kg −1) or the same diet supplemented with L-lysine or treated lysine (5.5 g lysine kg −1) in a cross-over experiment. Both lysine treatments caused six-fold increases in the concentration of lysine in the blood plasma between 1 and 2 h after feeding. The concentrations of lysine in plasma returned to pre-feeding levels 6 h post-feeding. In the second experiment, the basal diet supplemented with the two forms of lysine was given to 6 pigs. The apparent digestion of lysine to the terminal ileum was found to be complete for both forms.