Gastric emptying of solid, non-digestible, radiopaque markers in ponies

The gastric emptying of different forms of ingesta occurs by a variety of mechanisms and dysfunction may selectively affect different components of the gastric contents. A technique for assessing gastric emptying of solid, indigestible, radiopaque markers was developed. Emptying of these markers in four ponies was variable in both pattern and rate (half emptying time ranged from less than one hour to more than 24 hours). However, whereas in man physically similar markers appear to empty relatively rapidly when fasting but are delayed by a meal, no such delay was evident in these ponies. The horse does not interrupt cyclical motility when fed ad libitum. The data, therefore, suggest that the mechanism of emptying of non-digestible markers differs between man and the pony.