Fasting and Feeding Effects on Gastric Emptying Time in Juvenile Swine

Gastric emptying time in juvenile swine was examined radiographically after administration of a barium sulfate bolus. Animals were manually restrained for the radiographs, a simple and non-traumatic procedure that enabled us to easily track the barium. Animals were fed at pre- and post-dose intervals and radiographed at timed intervals until the barium had cleared the stomach. There was rapid clearance of the bolus (2 h) after an overnight fast; however, feeding 4 h prior to dosing slowed completion of gastric emptying to 4 h. Although most of the bolus had already cleared the stomach, feeding at 2 h post-dosing accelerated movement of the remainder. Uptake of any ingested material is related to residence time in the stomach; these trials show that this time is influenced by feeding intervals, both pre- and post-dosing. If residence time in the stomach is a determinant in toxin absorption, by implication, it may be possible to use feeding times as a tool to reduce or increase toxin bioavailability.