How do they do it? The Amazing Canine Nose can sniff out smells we don’t even know exist.
Want to know how a dog’s nose helps humanity- rescue, military, medical and enforcement teams? Well, for starters, there are 200 million scent receptors in the dog olfactory system (as compared to a puny 5 million in us humans) help sniff out drugs and explosives, locate termites, gas pipeline leaks, and other things you may not know about, or for that matter, even really want to know about. Dogs were used recently to locate casualties following San Bruno explosion and fire. Keep reading and learn how dogs do it.
The Amazing Canine Nose The canine’s extraordinary sense of smell serves humans in many ways. Most people know about dogs who track missing people and about drug-sniffing dogs who search out explosives, guns, and other contraband as well as cadaver material. According to the Alabama Cooperative Extension System, US Customs and Border Protection employs more than 800 canine teams that work with the US Dept of Homeland Security. Its Canine Enforcement Program uses a variety of breeds including German Shepherds, Labrador Retrievers, and mixed breeds. Beagles are used to detect prohibited items at ports of entry.
Read the National Geographic reporton how > the Beagle Brigade is used as our nation’s first line of defense against bad bugs and contaminated foods from foreign countries.
However, these nasal powerhouses also help us locate gas pipeline leaks, as in San Bruno, water leaks, building molds and winery molds, endangered species, termites, bedbugs, weeds that are hazardous to agriculture, and fruits and vegetables that may ship dangerous insects and diseases into the country. Medical research even indicates that cancer sniffing dogs may be useful in identifying cancerous tumors and other diseases..
Note:If you watch today’s PBS Nature program, “Dogs that changed the World, Part Two: Dogs By Design,” you will actually see a medical dog who is keeping a young boy alive through his keen ability to detect the most minute changes in the boy’s medical condition. Locally,San Jose/Bay Area) tune in at 8 PM, KQED Chanel 9 and prepare to be amazed. > Please check out my review.
How the Dog Nose Works: The canine olfactory system consists of soft tissue, bones, nerves, and parts of the brain. The soft tissue and bony structures make up the cavities into which odor particles flow. These cavities are lined with scent receptor cells which connect to olfactory nerves that connect with the olfactory lobe of the dog's brain.
Dogs have large folds of mucous membranes inside their nose containing more than 200 million scent receptors compared to smaller areas of mucous membranes containing about 5 million in humans. Their olfactory bulbs are also about 4 times larger than ours. However, some breeds are better suited for scent work than others. Longer muzzled dogs have more scent receptors than do short nose dogs.
Here’s some fun facts.
Different parts of the dog you might not expect aid in detecting scents. You know thoselong, funny ears hounds have? Well, they act like air scoops to draw up more scent particles. And those adorable wrinkles of breeds like the Bloodhound? Would you believe they actual help capture and hold scents to intensify the dogs ability to track them? They do!
Now for a little scientific tidbit*
According to Dr. Gary Settles, professor of mechanical engineering at Penn State, when a dog sniffs, he uses a different route of airflow than for normal breathing. A structure just inside the nostrils called the alar fold, opens allowing air to flow through the upper area of the nasal passages. A bony pocket traps odor molecules and they are dissolved in the mucous covered scent receptors. This chemical change signals the receptor along the olfactory nerve to the olfactory bulb at the end of each nasal passage.
When the dog exhales, the alar fold closes off the upper part and pushes air down and out through the slits on the side of the nose, which stirs up even morescent particles.
Odor molecules emanate from the source in a cone shape. Depending on environmental factors, odor molecules will be denser at the source and thinner as they disperse into the air. Scent detection dogs will scan this scent cone as they trail the source, often making a ‘whuffing’ sound.
So, what this is comes down to in simple terms is:
Tracking Dogs are able to track to the source by following the ever increasing density of the odor molecules.
Medical dogs , onthe other paw who remain close to a patient,sense changes in the molecules, alerting the medical staff or parent that attention is needed.
Okay, now that you know how they do it, please check back for my article on SAR(Search and Rescue) Dogs, and the wonderful things they do for us.
Woof for Now
Wrapping my arms all around all things Dog
Here is more for you truly inquisitive types
The Tracking Dog's Nose: How K-9 Drug Sniffing and Scent Detection Works
Working Dogs and the Jobs They Do
*Article Facts Source:Cadaver Dog Handbookby Andrew J. Rebmann, Marcella H. Sorg, Edward David > VeterinaryPartner.com
