DIET PREFERENCE IN RATS (RATTUS-NORVEGICUS) AS A FUNCTION OF ODOR EXPOSURE, ODOR CONCENTRATION, AND CONSPECIFIC PRESENCE

The relative contributions of social and stimulus factors in developme nt of rat dietary preferences were examined. Investigation of odor-alo ne effects revealed that weak odors resulted in preference for familia r odor diets, but only at longer exposure times. Shorter exposure to s trong odors also produced differences in diet preference. When odor an d conspecific presence were manipulated simultaneously, odors produced no diet preference at low intensities, whereas high-intensity odors d id so regardless of conspecific presence. Medium-intensity odor concen trations produced differences only with conspecifics present, indicati ng social enhancement of stimuli that are ineffective in isolation. Th ese results suggest the separate influence of social and stimulus fact ors on dietary preferences and explain contradictions in previous stud ies.