Alarm substance emitted by rats in the forced-swim test is a low volatile pheromone.

A series of studies was conducted to determine if the alarm substance produced by rats in the forced-swim test satisfies criteria for pheromones: well-defined behavioral effect, species specificity, minimal influence of experience and control for nonspecific arousal. The alarm substance satisfied these criteria. Additional studies involving activity testing in the presence of the alarm pheromone and preference/avoidance for odors emanating from cylinders containing the pheromone indicated it has very low volatility.