Biologically relevant odors, including those related to predators, produce unconditioned fear and anxiety-like behaviors, such as risk assessment, avoidance and freezing as well as conditioned place avoidance. In addition to predator odors, social stress can promote anxiety-like behaviors. When a male Syrian hamster (Mesocricetus auratus) is confronted and socially defeated by the Resident Aggressor, a larger and more aggressive male, it results in reduction in aggression and an avoidance of a smaller, non-aggressive conspecific. While there are many studies examining the effect of predator odors on defensive responding in rats and mice, there is currently a dearth of information using hamsters as test subjects. In this study, social defeat in combination with an adverse stimulus odor exposure was used to evaluate innate versus conditioned avoidance and anxiety-like behaviors in male Syrian hamsters. We hypothesized that while coyote and conspecific odor exposure without social defeat will elicit innate and conditioned avoidance respectively, animals socially defeated will show heightened avoidance. These results will not only add to the existing literature regarding the neurobiological basis of conditioned avoidance behavior, it is among the first to examine predatory avoidance behaviors in hamsters.
