The influence of intestinal infusion of fats on small intestinal motility and digesta transit in pigs.

Abstract

SUMMARY1. The influence of duodenal and ileal infusion of nutrients on small intestinal transit of digesta, measured by the passage of phenol red marker, was studied in twelve pigs fitted with duodenal and ileal catheters, and a terminal ileal cannula.2. Changes in gastrointestinal motility were observed by electromyography and by use of an X-ray image intensifier in four of the pigs fitted additionally with nichrome wire electrodes in the gut wall and in seven pigs fitted only with a gastric catheter.3. Small intestinal transit time was unaffected by intestinal catheterization per se, or by duodenal or ileal infusion of glucose or peptone. It was reduced by duodenal infusion of fat or of some of the products of fat digestion including oleic acid and a monoglyceride containing unsaturated fatty acids (monoglyceride LS) but was not affected by infusion of glycerol, stearic acid or a monoglyceride containing saturated fatty acids (monoglyceride P).4. Ileal transit time was greatly reduced by ileal infusion of soya bean oil mixed with bile salts and lipase and by monoglyceride LS but not by soya bean oil alone. Total small intestinal transit time was reduced to a lesser degree by ileal infusion of soya bean oil mixed with bile salts and lipase and by monoglyceride LS and was unaffected by soya bean oil alone.5. The level of irregular spiking activity of the small intestine was greatly reduced by both duodenal and ileal infusion of fat, but rapidly propagated spike bursts were initiated from the point of infusion (identified radjologically as peristaltic rushes) many of which travelled right through to the ileo-caecal junction.6. It is concluded that intestinal infusion of fat accelerates small intestinal transit in pigs by induction of peristaltic rushes; that since the ileal transit times were more severely reduced than total small intestinal transit times by ileal infusion of fat the response is probably only seen over those areas of intestine in direct contact with the fat; and that the effect depends upon the presence of fat digestion products, i.e. the fatty acid and the monoglyceride, although probably only those containing unsaturated fatty acids.

The Influence of Rapeseed Oil on Digestibility, Energy Metabolism and Tissue Fatty Acid Composition in Pigs

“…This hypothesis is based on the assumption that the time required for protein digestion is a limiting factor. However, it has been shown that infusion of fat into the duodenum of pigs accelerates intestinal digesta transit (Gregory et al, 1986). Dietary fat has a depressing effect on the intestinal microflora, especially in the hind-gut, which is indicated in the present study by slightly lower methane production at the highest rapeseed oil level (Table 3).…”

The influence of gastrointestinal infusion of fats on regulation of food intake in pigs.

“…This contrasts with findings in man where ileal infusion of undigested fat inhibited intake in excess of the level of energy infused (Welch et al 1985), perhaps via activation of an 'ileal brake', a slowing ofdigesta transit through the small intestine and slowing of gastric emptying (Read, McFarlane, Kinsman, Bates, Blackhall, Farrar, Hall, Moss, Morris, O'Neill, Welch, Lee & Bloom, 1984;Welch et al 1985). An 'ileal brake' mechanism appears to be absent in the pig, for ileal infusion of undigested fat or fat digestion products accelerates rather than slows transit through the small intestine (Gregory, Rayner & Wenham, 1986). This might explain why no immediate inhibition of food intake was seen in the present study.…”

Characteristic of duodenal myoelectric activity in relation to food in piglets during the 3rd and 4th week of life

“…In adult pigs, however, the MMC is interrupted when the animal is fed discrete, large meals, but not by ad libitum feeding with the same diet (Bueno and Ruckebusch, 1976). Other research has shown that the caloric load regulates the characteristics of the amplitude of contraction and the duration of the intestinal postprandial pattern in adult pigs (Gregory et al, 1986), dogs (Schang et al, 1978;Schmid et al, 1992) as well as in adult humans (Schönfeld et al, 1998). Furthermore, it was demonstrated in adult dogs that during enteral infusion of low caloric load, MMC persisted, apart from a lengthening of phase II and resulting increase in duration of the MMC cycles; only higher caloric load caused complete disruption of the MMC and appearance of postprandial pattern (Defilippi, 2003).…”