03/18/2025
It’s Tuesday and time for a tidbit!!
How strong is a dog’s nose? It is estimated that dogs can smell anywhere from 1,000 to 10,000 times better than people. They have more than 100 million sensory receptor sites in the nasal cavity compared to 6 million in people, and the area of the canine brain devoted to analyzing odors is about 40 times larger than the comparable part of the human brain!!
Why do dogs smell better? Dogs have an additional olfactory tool that increases their ability to smell. Jacobsen’s organ (or the vomeronasal organ) is a special part of the dog’s olfactory apparatus located inside the nasal cavity and opens into the roof of the mouth behind the upper incisors. This amazing organ serves as a secondary olfactory system designed specifically for chemical communication. The nerves from Jacobsen’s organ lead directly to the brain and are different from the other nerves in the nose in that they do not respond to ordinary smells. In fact, these nerve cells respond to a range of substances that often have no odor at all. In other words, they work to detect “undetectable” odors.
Jacobsen’s organ communicates with the part of the brain that deals with mating. By identifying pheromones, it provides male and female dogs with the information they need to determine if a member of the opposite s*x is available for breeding. It also enhances a newborn pup’s sense of smell so he can find his mother’s milk source, and allows a pup to distinguish his mother from other nursing dogs. With a quick sniff, a pup placed between two females will migrate to the mother that gave birth to him. Pups also have heat sensors in their noses that help them locate their mothers if they wander away.
The two separate parts of the dog’s odor detection system, the nose and Jacobsen’s organ, work together to provide delicate sensibilities that neither system could achieve alone. When the dog curls his lips and flares his nostrils, he opens up Jacobsen’s organ, increases the exposure of the nasal cavity to aromatic molecules and essentially becomes a remarkably efficient smelling machine.
Excerpt from How Dogs Use Smell to Perceive the World, By Ryan Llera, BSc, DVM; Lynn Buzhardt, DVM