Study On Absorption Of Oligopeptides In The Small Intestine Of Sheep

This paper mainly studied on absorption of oligopeptides in the small intestine of sheep by arterio-venous catheter technique and different level and nutrients infusion technique, and discussed the effects of different concentration and sources of peptides on absorption of oligopeptides in the small intestine of sheep. It also calculated the absorption rate of oligopeptides in the small intestine of sheep and the synthesis rate of peptides from FAA by gut wall by measurement of MDV, PDV net flux of peptides. The purpose of this study is to gain some basic data for protein nutrition manipulation for ruminants and to make the ruminant new protein system more perfect in practice. Part 1: Study on absorption of oligopeptides in the small intestine of sheep by intraduodenally infused different concentrations of small peptides. Trial 1: Five wethers of Inner Mongolian semi-fine wool sheep , fitted with permanent cannulas in the rurnen and at the proximal duodenum and terminal ileum were used to investigate the net flux of peptides in the duodenum and ileum and the apparent disappearance of peptides in the small intestine of sheep fed 12 times daily. The results showed that the peptides-N fluxes in the duodenum and ileum of sheep were 56.33mgNIh and 1 6.66mgNIh, respectively. The apparent disappearance of peptides-N of sheep were 70.42%. Trial 2: In a 4 X 4 randomized block design, four sheep in each group fitted with runiinal, duodenal and ileal cannulas and with carotid artery, mesenteric and portal venous catheters were used to study effect of intraduodenlly infused peptide on peptide digestion, absorption in the small intestine and the net fluxes of MDV and PDV. Four infused peptide levels, i.e. 0, 1.15, 2.15 and 3.15g/d, were used, which resulted in 1.35g1d, 2.50g/d, 3.SOgId and 4.50g/d of peptides entering the duodenum. The results showed that as peptides infused level was increased, The portal, mesenteric and arerial concentration of peptides, the net fluxes of MDV, PDV and TMAA were all raised significantly (P<0.05 or P<0.0 1). Further investigation showed, as peptides infused level was increased, the most PBAA and FAA also raised significantly (P