Investigation on the amino acid secretion and absorption in the stomach of the growing pig

2 pigs of 35 kg live weight were fitted with re-entrant duodenal cannulas anterior to the pancreatic duct and fed on barley-soy and casein-wheat starch diet, resp., prior to the experiment. After 24 hours fasting they were given a single meal of 15N-labelled free amino acids-wheat starch (A) or 15N-labelled wheat (B) diet and digesta leaving the stomach were collected during 12 hours. The proportion of TCA soluble N in total N of digesta increased with time from 10% to 40% with diet B and decreased from 90% to 47% with diet A. Total N leaving the stomach within 12 hours accounted for 96% and 106% of N ingested on diet A and B, while the amount of 15N accounted for only 66% and 86% of 15N given in diets A and B, resp. The content of endogenous N in the digesta were 1.22 g/12 h after feeding diet A and 1.67 g/12 h after feeding diet B. It was concluded that considerable amounts of N are secreted and absorbed in the part of the digestive tract proximal to the opening of the pancreatic duct. (author)