The dog nose arrived at my house in a box that said it contained a Corelle eighteen-ounce soup/cereal bowl. At the time, I had no idea what was actually inside. Gus barked the UPS truck good riddance while I checked the name on the return address. It was definitely not a bowl. It had been weeks since Matthew Staymates, PhD, a fluid dynamicist and mechanical engineer with the National Institute of Standards and Technology (NIST), had said he would send me something interesting. It felt like Christmas in May as I drew the knife in a shallow track along the tape. The top of the box popped open like double doors to reveal a wad of crinkly brown paper. What could it be? Gus was curious, too. He stood by me at the kitchen counter, his yellow Lab face smiling, his big brown eyes glancing from me to the package and back to me. Open it! Open it! What did we get?! I pulled away one corner of the paper, then the next. Something white and cylindrical peeked out. It looked like a cup. A cup? I ripped through the rest of the paper. In my hands I now held a heavy-duty hard plastic replica of a dog's nose. Not some cheap costume-shop version, but a 3-D-printed model of the exterior of a real dog's snout, life-size. It was all white except for the soft black rhinarium (the cold wet part of a dog's nose), with a perfect rendition of the nostrils, down to the little curvy slits on the side. The inside of this particular nose was mostly hollow. It wasn't anything like the intricate interior anatomy that makes a real dog's nose such a superb sniffer. When I held it with the nostril end facing down, it looked like a strange Japanese teacup that would never balance on a table. "NIST" was written in it with a Sharpie. From my interviews with Dr. Staymates, I knew he had created this nose himself on a 3-D printer. He used CAD (computer-aided design) files that had been supplied to him by fellow fluid dynamicist Brent Craven, PhD, who had created models of the complex inside of this same dog's nose. Compared with Dr. Craven's model, this nose was simplicity itself. And yet even this simple structure has been shown to vastly improve detection of odors when applied to a "sniffing" system. When Dr. Staymates and his colleagues used a similar design on a vapor detection system and had it mimic the way dogs sniff-inhaling and exhaling about five times a second rather than just drawing in air-vapor detection improved sixteen-fold. This kind of canine biomimicry, when put to use with technology that already exists, could have far-reaching effects for future scent detection. As Dr. Staymates and his colleagues wrote in Scientific Reports journal Nature, "These lessons learned from the dog may benefit the next-generation of vapor samplers for explosives, narcotics, pathogens, or even cancer . . ." The mere shape of the outside of a dog's sniffer can lead to possibly lifesaving technologies? This was my cup of nose. I've been writing about dogs for thirty years. It's been a joy to be able to focus part of my journalism career on these loyal, fun, intelligent, beautiful creatures. And now is an especially exciting time to be writing and reading about dogs. Never has there been so much interest in the hearts, minds, and noses of dogs as there is today. As I wrote this book, I kept the nose on an empty corner of my large desk. It stared at me with its soft plastic nostrils, cheering me on and reminding me of a key theme at the core of the book. Dogs can smell in parts per trillion. Craig Angle, PhD, codirector of Canine Performance Sciences at Auburn University's College of Veterinary Medicine, likens this to being able to sniff out a teaspoon of a chemical in a million gallons of water-or the equivalent of nearly two Olympic swimming pools. Our own sense of smell is much better than most of us think it is. But we're limited. Dogs have a big advantage by virtue of their olfactory anatomy. We have about six million olfactory receptors in our noses. Dogs have up to three hundred million. They sniff in 3-D, with each nostril sampling air separately, which helps them locate a scent. And the brains of dogs are better equipped to make sense of the scents. Yet as good as they are, dogs don't rank among the best sniffers in the world, at least when measuring olfactory receptor genes. In a Japanese study of thirteen mammals, African elephants had twice as many functional olfactory receptor genes as dogs. Also ranking above dogs were rats, mice, cows, and horses. Humans placed just barely above other primates, which had the lowest number of genes associated with smell in the study. The researchers didn't include bears, which are known to have a phenomenal sense of smell. Sharks and other nonmammals known for their olfactory abilities also weren't part of the study. Even if canines aren't the olfactory superstars of our planet, they're top dog when it comes to working alongside us to detect scent. They've long been our faithful assistants for jobs like explosives and narcotics detection, search and rescue, hunting, human tracking, bedbug detection, sniffing for cell phones in prisons, and rooting out certain foods from luggage at airports. They've recently been helping humans in unprecedented ways. The list of jobs involving a dog's sense of smell continues to expand as training techniques and our knowledge of dogs improve. Dogs are searching for the feces of several species listed as vulnerable, threatened, or endangered, including orcas, tigers, giant anteaters, jaguars, and certain bears and wolves. This helps conservationists keep track of everything from the populations of these animals to their illnesses and diets. Dog noses are also tracking down water leaks in Western Australia, rhino poachers in Africa, cremated remains, old bones of interest to archaeologists, elephant tusks, counterfeit money, and ancient artifacts. And recently dogs have been using their olfactory skills on something that might prove most important of all: our health. Scientists and top-notch trainers are working together around the world to help canines help us with some of our biggest health concerns-everything from early cancer detection to diabetes control to stopping the spread of deadly bacteria. The dogs in this book are on the cutting edge of science. Some of these coveted "biodetection" dogs work in homes, as service dogs. Others are regular pets whose people bring them into training centers and laboratories (which are truly fun places) to help researchers uncover the scents of disease. Most of the dogs in this book rely on their noses for their jobs, although many of the service dogs use a variety of senses. Traditional service dog jobs like guiding the blind and helping the hearing impaired will always be in demand. But the world of the new "doctor dogs" is using the talents of dogs in ways we never would have dreamed at the beginning of this century. Some dogs use their nose for a living. Gus smells for a living. There is a difference. It seems to be Gus's calling to want to become certain scents. Or at least to wear them in style. If he really likes something, he'll do his best to get it all over his body. This is usually accomplished by rolling in the scent, or at least sliding into it with his head and shoulders. Gus is selective about the substances he likes to wear. They're usually one of two categories: poop or dead animals. He will roll in grass, like normal dogs, but only if it has a specimen from one of these categories. Sometimes he also goes for urine. In Golden Gate Park, we often pass by the police horse stables on our walks. Lately we've been coming across mounds of used straw near the corral. The first time we encountered one, Gus sniffed the air and dived into it, joyfully rolling and scratching his back for a few seconds, standing up, and crashing into it again. I laughed to myself about him having a literal roll in the hay. But Gus got the last laugh, because as we continued our walk, I noticed a wretched stench-like used diapers festering in a bin. I sniffed and looked around for the source because I couldn't shake it. Then I realized it was emanating from the bouncy, grinning Labrador retriever, and the stink was old horse urine. Why, Gus, why? I later learned that some wolves like to roll in the poop of carnivores such as cougars or black bears. And gray foxes seek areas frequented by male mountain lions and rub their faces in it. Could it be a form of camouflage? Some researchers think so. Others think it might be a way of carrying the odors of their journey back to the pack-kind of like the canine version of Instagram or Facebook. Maybe. Or something else? On a sunny mid-February hike along a rugged leashes-optional coastal trail about fifteen minutes south of home, Gus cantered off ahead about twenty feet and threw himself down into something I couldn't see. When I caught up with him a few seconds later, he had just completed a thorough body rub on his left side. "Gus!" He stood up and looked at me. Yeah, I know, can you believe I found this? It's so great, isn't it?! I looked where he had been rolling and saw what had lured him. It had the familiar shape of feces, but consisted primarily of a former animal, or part of one. It was hairy, twisted, and dark gray. Coyote poop. Gus beamed. He held his head high and wagged his tail in the same proud way he does when gets a new bone or ball. It struck me that he felt like he was now part coyote (not that I read into my dog's behaviors or anything). A little way down the trail, as I was admiring the ocean view, he plowed to the ground again, left shoulder first. This time it was a pile of fresh horse manure. When I stopped him, he stood up and seemed just as thrilled as he had with the coyote-poop incident. Now he was part horse, part coyote, and part Gus. As we came to other dogs on the trail, he approached them in a different manner than normal-still friendly, but with a check ME out vibe. Sure enough, the dogs would run up to him and sniff Gus-this multi-animal wonder. They lingered on his left side, where he apparently smelled of both horse and coyote. (Thankfully, unlike during the horse-urine incident, his odor wasn't obvious to the human nose.) The older dogs would move along after a good inspection, but the younger dogs followed him around, sniffing more, wagging fast-clearly in admiration of this cool guy. He seemed to revel in the attention, walking slowly by them and standing with his left side for them to ogle again with their noses. When we got home, the hose came out and washed away his hard-won glory. IÕve often wondered if Gus could be a detection dog of some sort if he had the training. HeÕs only three years old, and he has the nose for it; he has high drive for a reward of food or a ball and enjoys learning new skills. But what kind of detection would he do? For personal reasons, it would be handy to me if he could be a cancer-detection dog. Even just a self-trained one. When it comes to cancer detection, I have a dog in this fight-skin in the game. Or, actually, body parts in the game. In 2001, after a lifetime of radiant health, my amazing mom, Evelyn DeMagistris Goodavage, was diagnosed with stage IIIC ovarian cancer at age sixty-eight, seemingly out of the blue. A large mass was discovered during a routine annual checkup. There had been no sign of anything amiss during her previous exams. Mom made it two weeks past her seventieth birthday, after two massive surgeries, chemotherapy, and a cruise through the Panama Canal. I would later discover that a few relatives on the Italian side of the family died from this cancer. I did the genetic tests my doctor recommended, and nothing came up as positive. But the geneticists still think I'm at high enough risk for the disease that I should consider preventative surgery. This is not something I want to have to do. The problem is that, as with several other cancers, there's no good early screening for ovarian cancer. The American College of Obstetricians and Gynecologists issued a statement saying, "Unfortunately, the existing evidence does not support any test to effectively screen for ovarian cancer. More research is still needed . . . [A]t this time, there is no effective strategy for ovarian cancer screening. Available ovarian cancer screening tests . . . are neither accurate nor reliable to screen asymptomatic women for early ovarian cancer." Ovarian cancer is known as "the silent killer." Often there are no symptoms, or if there are, they're so common-like bloating, indigestion, and lower back pain-it's easy to attribute them to something more benign. As a result, most cases of ovarian cancer are found in later stages, when survival rates are low. It's the fifth-leading cause of cancer deaths in women in the United States. Living without a cancer safety net can be unnerving. I try not to think about it. But in the beginning of researching this book, I drove up to the In Situ Foudation, in Chico, California, to meet with Dina Zaphiris, a dog trainer who was involved in one of the earliest studies using dogs to detect cancer. And I did something I'm embarrassed to admit. Dina's star dog, Stewie, an Australian shepherd, has been trained to detect the presence of breast and ovarian cancer in laboratory samples. As you'll see throughout the book, scientists think that dogs who detect cancer and other diseases or conditions may be picking up on volatile organic compounds (VOCs). In a nutshell, VOCs are chemical substances released into the air. They can be natural or man-made. You may have heard of this term in relation to paints or solvents, but scientists reported in the Journal of Breath Research that they detected 1,840 VOCs in healthy humans. (They considered breath, saliva, blood, milk, skin secretions, urine, and feces.) Dogs like Stewie seem to be able to detect disease-specific VOCs. Stewie is just a regular dog most of the time, enjoying a hearty belly rub or a chase around the pasture as much as any canine. But Dina explained that sometimes Stewie finds it hard to find the "off" switch outside In Situ's research facility-a pleasant farm-style building on the outskirts of town. Excerpted from Doctor Dogs: How Our Best Friends Are Becoming Our Best Medicine by Maria Goodavage All rights reserved by the original copyright owners. Excerpts are provided for display purposes only and may not be reproduced, reprinted or distributed without the written permission of the publisher.
