[Protein and amino acid digestibility in different sections of the intestines in the pig. I. Protein sources of animal origin].

Growing pigs were provided with ileocaecal re-entrant cannulae to make it possible to investigate the protein and amino acid flow in various parts of the digestive tract. The three animal protein sources casein, dried skimmed milk and fish meal were tested. Information is given on the values of the crude protein and amino acid flow in the digestive tract as well as the apparent and true digestibility of the crude protein and the amino acids for the individual sections of the intestines (small and large intestine). After rations far surpassing the amino acid requirement an increased excretion of endogenous amino acids in the small intestine has to be expected. Digestion studies have to take more account of this circumstance.