Is there anything for which a dog can't use its nose to figure out? Dogs have long been used to sniff out escaped convicts and missing children (think bloodhounds), dinner (think spaniels, retrievers and hounds), and even truffles (think poodles).
In recent years, trainers have come up with all kinds of new ways to use a dog's extraordinary sense of smell.
Here are a few you may know – and a few more we bet you did not:
Drugs: Dogs can be trained to sniff out all kinds of illegal drugs, finding them not only on people but also in massive cargo containers, long-haul trucks and school lockers.
Plant matter: Since fresh fruits and vegetables can carry insects and diseases that have the potential to cause great damage to agriculture, dogs are used to detect foodstuffs in the luggage of travelers coming through customs. Dogs are also used to sniff out invasive plants in fields, so they can be eradicated before they take hold.
Insects: Termites? No problem. Dogs are also being used to detect the resurgence of bedbugs in big cities.
Mold: It's not just the mold that bedevils homeowners, but also the mold that puts the vines at wineries at risk from the spread of disease.
Explosives: Meetings of important public officials would be hard to imagine without the diligent work of bomb-sniffing dogs. To take it a bit further, dogs are even being taught to sniff out cellphones that could be used to detonate a bomb.
Cows in heat: A lot of money depends on being able to artificially inseminate a cow without wasting time guessing when she's ready. While a bull could tell, he's not always available, as his contribution usually arrives on the scene frozen. A dog can tell when the cow is most fertile, although it's a good bet the dog couldn't care less.
Cancer: While cancer detection is still in the trial stage, it's looking pretty promising that dogs can spot a malignancy. Someday your doctor may order up a "lab test" and mean Labrador retriever!
Chemicals: Dogs have been known to look for items as varied as mercury and the components of potentially pirated DVDs. They've also been used to detect the presence of fire accelerants in cases in which arson is suspected.
While most of us tend to think scent work is the near-exclusive province of a handful of breeds – bloodhounds, German shepherds and maybe a Labrador retriever here and there – in fact, many breeds and mixes can be trained to respond to various scents. Because of their fine noses and friendly dispositions, beagles are used to work airports by the U.S. Department of Agriculture, and any manner of mixed breeds – lucky dogs pulled from shelters – have been used for other kinds of detection work.
Because all dogs have keen noses filled with many more scent receptors than we humans have, a dog's future doing nose work relies more on enthusiasm, reliability and trainability than on the common canine ability to tell one scent from another.
Pet Connection is produced by a team of pet-care experts headed by veterinarian Dr. Marty Becker and journalist Gina Spadafori. The two are also the authors of several best-selling pet-care books. Email them at firstname.lastname@example.org or visit www.petconnection.com.