Delays after eating: Effects on transmission of diet preferences and aversions

Previous studies have demonstrated that a naive rat (an observer), after interacting with a previously fed conspecific (a demonstrator), will exhibit an enhanced preference for the diet its demonstrator ate. Furthermore, observers poisoned after interacting with demonstrators exhibit an aversion to their respective demonstrators’ diets. In the present paper, we examined the effects, on transmission of information from demonstrator to observer, of introducing delays between the end of demonstrator feeding and initiation of demonstrator-observer interaction. We found that (1) for at least 4 h after ingestion, demonstrator rats emitted diet-related cues sufficient to alter observers’ subsequent diet preferences, and (2) diet-related cues emitted by demonstrators for 1 to 2 h after a meal were adequate conditional stimuli for aversion learning by their observers.