COMPOSITION OF ENDOGENOUS ILEAL DIGESTA NITROGEN FROM THE RAT - THE USE OF DISTILLED WATER FOR DIGESTA COLLECTION

The composition of endogenous nitrogen (N) in digesta from the distal ileum of the growing rat was determined following the collection of digesta using different flushing media. Twelve growing rats were given a protein-free diet for 6 days, and samples of digesta were collected from the terminal 20 cm of ileum of each euthanased animal using either distilled water or physiological saline as the flushing medium. The digesta samples were centrifuged and the supernate was ultrafiltered. Nitrogen and amino acid contents were determined in the precipitate plus retentate (MW > 10000 Da) and ultrafiltrate (MW < 10000 Da) fractions, as well as urea, creatinine, ammonium and free amino acids in the ultrafiltrates. There was no significant effect of collection method on the levels of N-containing substances in rat endogenous ileal digesta.