CASE STUDY: The pig pheromone androstenone, acting as an interomone, stops dogs from barking

Some dogs display behaviors such as excessive barking and jumping. Unwanted behaviors can often lead to animal abuse or pet relinquishment to a shelter. This study focused on the effects of androstenone on the behavior of dogs showing a barking and jumping syndrome. In the first study, barking dogs were sprayed with (a) nothing, (b) a placebo spray with sound or noise, (c) the same as (b) plus 0.1 μg/mL androstenone in isopropyl alcohol, (d) the same as (b) plus 1.0 μg/mL androstenone in isopropyl alcohol. Dogs were videotaped for 1 min after treatment was applied. Treatments were effective at stopping barking and jumping in 25, 44, 78, and 100% of the barking and jumping dogs, respectively. Videos of the behavioral effects are available for viewing online (see Methods). A second study examined the effects of androstenone on heart rate and behavior while dogs were calm. Four “anxious” dogs were fitted with telemetry jackets and transmitters, heart rate was monitored continually, and cameras recorded behavior. Dog heart-rate data were measured for 10 min before and treatment, 10 min after isopropyl alcohol spray, and 10 min after a spray in the snout with androstenone. Neither androstenone nor isopropyl alcohol changed the heart rate of dogs compared with baseline. The pig pheromone, androstenone, working as an interomone reduced excitable behaviors of dogs. Behavior modification using pheromones can improve animal welfare by reducing the incidence of unwanted barking and jumping behaviors in dogs. Androstenone stops dog excitability through the olfactory system. Androstenone is a pheromone produced by pigs but acts as a powerful interomone in the dog.