Technical Abstract: Studies in young pigs have shown that under conditions of continuous enteral feeding, the portal drain viscera (PDV) almost exclusively utilize arterial lysine. Since the mode of feeding might alter amino acid utilization kinetics, the aim of the present work was to quantify the postprandial kinetics of dietary and systemic lysine by the PDV and whole body after the ingestion of a large bolus meal. We found preferential first-pass use of dietary rather than arterial lysine during bolus feeding. We conclude that PDV lysine utilization shifts from the arterial to the enteral source as an increased dietary supply becomes available.