Determination of the endogenous N secretion in the porcine small intestine

In 3 pigs (live weight 15 to 27 kg) with a labial fistula at the end of the small intestine the endogenous N secretion was determined by isotope dilution. The animals received a single dose of a semi-synthetic diet with 15N-labelled dried curds as sole protein source. The passage rate to the ileum, determined by means of 51Cr2O3, was 70% in 24 hours. During the 24 hours test period the endogenous N in the ileum chyme amounted to 1.11 g and 56.6 mg/kg live weight, resp., 60% being present absorbable in the chyme at the end of the small intestine