Untersuchungen über die Proteinverdaulichkeit und Aminosäurenresorption in verschiedenen Abschnitten des Verdauungstraktes beim Schwein

Abstract

From two fattening pigs (average live weight 63 kg) with re-entrance cannulae both in the duodenum and the ileocecal region, the intake, the excretion and the flow rates of nitrogen, 15N, lysine and 15N-lysine are measured after the oral application of 15N-lysine as supplement of a wheat-wheat gluten diet. A scheme of the lysine metabolism of pigs is drawn on the basis of the measured values. The absorption of synthetic and native lysine as well as the endogenous and exogenous lysine contents of the duodenal and ileum chyme are estimated.

The flow of endogenous nitrogen in the digestive tract of young pigs

“…These results are similar to those of and Holmes et al (1974) obtained with cannulated pigs. Buraczewska et al (1979) and Wunsche et al (1979) described the flow of endogenous amino acids through cannulas in the terminal ileum of pigs even an N-free diet, and their values are approximately half those in the present experiment for the whole lower third of the small intestines; similarly the flow of total endogenous N was approximately half the level of the present study, as mentioned earlier. All the results discussed previously have referred to the flow of endogenous N in the digestive tract.…”

“…found that endogenous N secretion in the stomach and duodenum was unaffected by the protein level in the diet. However, in more recent reports by Krawielitzki et al (1979) and Buraczewska et al (1979), the flow of endogenous N and methionine to the duodenum was greater in pigs given a diet containing wheat gluten than when the diet given was N-free. Carlson & Bayley (1970) found that estimates of endogenous N flow by regression analysis in pigs given casein and those determined directly in pigs given an N-free diet were similar, but regression analysis with soya-bean meal as the source of dietary protein underestimated endogenous N. From the present experiment, it may be concluded that endogenous N flow can be estimated by giving an almost N-free diet or by regression analysis from pigs given diets containing casein.…”

“…In addition to the secretions from the pancreas and the gall bladder, the duodenal mucosa is glandular (Brunner's glands) and from this tissue there is a viscous, alkaline secretion which contributes to the endogenous N in the duodenum. The sloughing of epithelial cells would be the other source of endogenous N. The total endogenous N flow in the duodenum has been estimated to be approximately 3.C3.9 g/d per kg DM intake with 40 kg pigs given N-free diets Zebrowska et al 1975;Krawielitzki et al 1979). Slightly higher values of 5 g N/d per kg DM intake were obtained by Kohler et al (1978) and by Buraczewska et al (1979).…”

“…The sloughing of epithelial cells would be the other source of endogenous N. The total endogenous N flow in the duodenum has been estimated to be approximately 3.C3.9 g/d per kg DM intake with 40 kg pigs given N-free diets Zebrowska et al 1975;Krawielitzki et al 1979). Slightly higher values of 5 g N/d per kg DM intake were obtained by Kohler et al (1978) and by Buraczewska et al (1979). Kohler et al (1978) estimated endogenous N secretion by dilution of N15-labelled feed.…”

“…The amount of endogenous N passing the terminal ileum has been estimated at 1 4-1 4 g/d per kg DM intake by numerous workers Zebrowska et al 1975;Krawielitzki et al 1979;Wunsche et al 1979) in pigs given N-free diets. In the present experiment and in that of Wilson & Leibholz (1981b), the flow of endogenous N was estimated as 3-0-3-5 g N/d per kg DM intake in the whole lower third of the intestine.…”