The Relevance of Starch and Protein Digestive Dynamics in Poultry

摘要

The fundamental premise of starch and protein digestive dynamics is that an ideal balance of glucose and amino acids is made available at sites of skeletal muscle protein synthesis to promote efficient growth. Digestive dynamics involve the digestion of protein and starch in the gut lumen, absorption of glucose and amino acids along the small intestine and their transition across the gut mucosa into the portal circulation. However, the post-enteral, bilateral bioavailability of glucose and amino acids is ultimately dependent on their metabolic fates in enterocytes as both may be catabolized in avian enterocytes for energy to drive digestive processes. Importantly, digestive dynamics consider rates and sites of glucose and amino acid absorption along the small intestine in addition to their extents of digestion as determined by static digestibility coefficients. There is considerable interest in the development of low-protein/high-supplemental amino acid diets but the digestive dynamics of supplemental and protein-bound amino acids are inherently different. Therefore, the relevance of starch and protein digestive dynamics in poultry will become increasingly evident if low-protein diets are to be developed successfully in the future.