The effect of feeding on the motility of the stomach and small intestine in the pig

Abstract

1. Electromyographical studies were made on the motility of the stomach and small intestine of five pigs when given a standard diet eitherad lib., or as one or two meals/d. Recordings were made from electrodes placed chronically on the antrum, the duodenum and the jejuno-ileum, and a continuous 24 h recording was made every 2 d for a period of 4 weeks. A simple ‘T’-shaped cannula was positioned in the proximal duodenum in two of the pigs.2. The basic pattern of activity of the small intestine was grouped in phases of irregular and regular activity characteristic of the myoelectric complex. This pattern recurred about eighteen times/d in fasting pigs, or in animals fedad lib.and so eating frequent but small meals. When a myoelectric complex on the duodenum reached its regular ‘spiking’ phase, antral activity and passage of digesta ceased completely for a period (5–15 min) which varied according to the time elasped since the last meal.3. In animals receiving one meal/d a postprandial pattern of activity lasted about 6 h. The proximal part of the intestine showed continuous activity with vigorous isolated or peristaltic spike bursts. The average number of myoelectric complexes was thirteen/d. When receiving two meals/d the postprandial pattern lasted for only 2–3 h, and approximately sixteen myoelectric complexes/d were recorded.4. It is concluded that the extent of disruption of the basic intestinal motility pattern depends on the amount of food consumed per meal and subsequent release of nutrients.