Although canine reproductive behavior is easily observable, the underlying mechanisms of semiochemical communication remain complex and not fully understood. In this study published in Animals, Magdalena Woszczyło and colleagues examined whether urine from estrous females acts as a long-range pheromonal signal or functions primarily in close proximity interactions that precede mating decisions.
Two controlled experiments were conducted. In the first, five male dogs were exposed to volatile compounds from estrous female urine and live females, compared with food odors and clean air. Males showed greater interest in food scents than in estrous urine volatiles, indicating that urine odor alone did not induce sexual arousal at a distance. In the second experiment, 25 males were allowed to directly sniff and lick urine samples from females in estrus and anestrus, males, and humans. Estrous urine prompted significantly longer sniffing, licking, and salivation—behaviors observed only during direct contact.
The findings reveal that dogs rely on both volatile and nonvolatile compounds in female urine, which are processed through the vomeronasal organ during close-range investigation. This mechanism suggests that estrous urine is a short-distance communication signal rather than a long-distance pheromone. Such behavior likely supports precise reproductive timing and selective mating in domestic dogs.
This study enhances understanding of olfactory-driven mating communication and underscores that canine chemical signaling involves multi-layered sensory processing. The results also explain why artificial pheromone analogs have had limited success in replicating natural sexual attraction in dogs.
Source: Woszczyło, M., Jezierski, T., Szumny, A., Niżański, W., & Dzięcioł, M. (2020). The Role of Urine in Semiochemical Communication between Females and Males of Domestic Dog (Canis familiaris) during Estrus. Animals, 10. Published November 1, 2020.
