Briefly, a gadolinium‐based contrast agent was mixed with the animal’s meal in order for chyme to appear “bright” in MRI scans, thereby delineating the gastric and intestinal volume. A multi‐slice MRI sequence was used to scan the GI volume with high spatial resolution, and a similar sequence with a smaller spatial coverage was used to scan antral contractions with high temporal resolution. Measurements of gastric functions and physiology included the overall change in GI volume, gastric emptying, forestomach volume, corpus volume, antral volume, antral contraction frequency, antral peristaltic wave velocity, antral contraction amplitude, pyloric opening size, intestinal filling and, indirectly, absorption.