WEBVTT - What Happens If a Dog Loses Its Sense of Smell? 0:00:01.920 --> 0:00:06.680 Welcome to Brainstuff, a production of iHeart Radio Pay brain 0:00:06.720 --> 0:00:10.239 Stuff Lauren bog Obam. Here. When you take your dog 0:00:10.280 --> 0:00:12.520 for a walk, you know you're going to stop at 0:00:12.520 --> 0:00:16.400 every bush, fire, hydrant, mailbox, and any other marked item 0:00:16.440 --> 0:00:20.520 along the route. That's because dogs have highly sensitive sniffers. 0:00:20.920 --> 0:00:24.759 Their noses are constantly processing information left by other neighborhood 0:00:24.800 --> 0:00:28.840 dogs or critters that have passed through their turf. Scientists 0:00:28.920 --> 0:00:31.560 say a dog's sense of smell is ten thousand to 0:00:31.640 --> 0:00:35.559 a hundred thousand times more accurate than humans. Dogs have 0:00:35.600 --> 0:00:38.600 been trained to sniff for bombs at airports, to participate 0:00:38.640 --> 0:00:41.840 in search and rescue, and to even detect certain diseases 0:00:41.880 --> 0:00:46.919 like diabetes and possibly the novel coronavirus. But just like 0:00:47.040 --> 0:00:50.440 any other of the senses, including site, hearing, or taste, 0:00:50.960 --> 0:00:54.200 that sense of smell can disappear for a whole host 0:00:54.280 --> 0:00:57.640 of reasons. If it does, it can be confusing for 0:00:57.640 --> 0:01:02.640 the dog and challenging to diagnose. The loss or the 0:01:02.800 --> 0:01:06.319 decreased ability to smell is called a nasmia, and it's 0:01:06.360 --> 0:01:09.959 a fairly common symptom that people experience with illness or trauma. 0:01:10.760 --> 0:01:13.800 We heard about it most recently during the COVID nineteen pandemic. 0:01:14.640 --> 0:01:19.040 When it happens to people, we usually self report it. Unfortunately, 0:01:19.200 --> 0:01:22.520 dogs can't tell their people what's going on. Instead, they 0:01:22.560 --> 0:01:26.960 may pick up their food or otherwise behave strangely. We 0:01:27.040 --> 0:01:30.120 spoke with Dr Sarah Moore, a veterinarian and professor in 0:01:30.160 --> 0:01:33.640 the College of Veterinary Medicine at the Ohio State University. 0:01:33.880 --> 0:01:38.200 More also specializes in veterinary neurology and neurosurgery, and she 0:01:38.280 --> 0:01:40.959 says that it takes a very astute owner to pick 0:01:41.000 --> 0:01:45.000 up a nasmia in dogs. She said, when we diagnosed 0:01:45.080 --> 0:01:48.000 or documented nasmia in a dog, we're doing it based 0:01:48.000 --> 0:01:51.000 on changes in behavior patterns or things they used to 0:01:51.000 --> 0:01:55.040 do that they can't do anymore. It's quite hard, especially 0:01:55.040 --> 0:01:57.280 if it's just one side of the nose, if they 0:01:57.280 --> 0:01:59.520 can still smell out of the other can be really 0:01:59.560 --> 0:02:02.400 difficult for the owner to realize that there's something wrong. 0:02:04.280 --> 0:02:07.600 Owners typically bring dogs in when it's affected their work, 0:02:08.120 --> 0:02:11.240 for example, a police dog doing scentwork, or dogs the 0:02:11.240 --> 0:02:15.520 airport sniffing for explosives or drugs. More head a case 0:02:15.560 --> 0:02:18.160 of an osmia in a dog that was a bedbug sniffer. 0:02:18.840 --> 0:02:21.520 She said, the dog went to people's houses and smelled 0:02:21.520 --> 0:02:24.280 out bedbugs, and the owners noticed a change in the 0:02:24.320 --> 0:02:27.600 way he did his job. That often triggers the visit 0:02:27.639 --> 0:02:30.160 to the vet, and by then it's usually a complete 0:02:30.160 --> 0:02:32.920 loss of smell because those dogs are so good at 0:02:33.000 --> 0:02:38.639 compensating for any loss of smell. But what causes anosmia? 0:02:40.000 --> 0:02:42.880 More said, the list of concerns is going to include 0:02:42.880 --> 0:02:45.080 things like infections of the lining of the nose or 0:02:45.160 --> 0:02:48.600 chemical irritants. Things that can cause inflammation of the nose lining, 0:02:48.840 --> 0:02:52.720 whether that be infectious or otherwise. Also, problems of the 0:02:52.760 --> 0:02:57.080 brain can actually cause issues with smell. A dog's nose 0:02:57.160 --> 0:02:59.640 and the links between it and its brain are nothing 0:02:59.680 --> 0:03:04.359 short of astonishing for starters. When canines inhale, a fold 0:03:04.400 --> 0:03:07.440 of tissue inside the nostrils separates the air flow into 0:03:07.480 --> 0:03:11.200 two paths, one for old faction and one for respiration. 0:03:11.840 --> 0:03:14.600 About fifteen with the air is sent to the olfactory 0:03:14.639 --> 0:03:18.680 area as it's examined, recognized or not, and sorted before 0:03:18.680 --> 0:03:23.560 it's exhaled. That examination happens in the canine nasal cavity 0:03:23.720 --> 0:03:28.760 or olfactory lobe, positioned directly behind the nose itself. This 0:03:28.840 --> 0:03:31.960 lobe is lined with all kinds of tiny nerve cells 0:03:32.000 --> 0:03:35.320 that connect directly to the brain. Dogs have up to 0:03:35.400 --> 0:03:39.280 three hundred million olfactory receptors depending on the breed, compared 0:03:39.280 --> 0:03:43.800 with only about six million in humans. More said, in dogs, 0:03:43.880 --> 0:03:46.760 the olfactory lobe is massive. If you were to look 0:03:46.800 --> 0:03:50.000 at a dog's olfactory lobe compared to a humans, it's huge. 0:03:50.000 --> 0:03:52.600 In a dog, it's because their sense of smell is 0:03:52.640 --> 0:03:55.960 so highly developed. Problems in that area of the brain 0:03:56.120 --> 0:04:00.520 can cause altered smell, so tumors of the brain, strokes, 0:04:00.560 --> 0:04:03.640 head trauma, injury can all impact the sense of smell. 0:04:05.080 --> 0:04:08.720 That's a long list of potential issues. However, once the 0:04:08.800 --> 0:04:12.560 veterinarian knows what's causing the anosmia, it can usually be treated. 0:04:13.240 --> 0:04:16.320 Sinus infection is typically caused by bacteria and thus treated 0:04:16.320 --> 0:04:19.280 with antibiotics. If the problem is brain related, such as 0:04:19.279 --> 0:04:22.040 a tumor, surgery may be an option, or if they 0:04:22.040 --> 0:04:26.400 can try radiation therapy. The loss of smell is temporary 0:04:26.440 --> 0:04:29.680 when caused by an allergic reaction to medication or exposure 0:04:29.720 --> 0:04:32.719 to chemicals or other irritants, and will usually wear off 0:04:32.720 --> 0:04:36.599 with time, though some loss of smell may linger. However, 0:04:37.000 --> 0:04:40.120 viral infections that cause loss of smell could become permanent 0:04:40.240 --> 0:04:45.080 depending on what virus causes it. More says that questions 0:04:45.080 --> 0:04:47.640 about the link between aging and an osmia in dogs 0:04:47.800 --> 0:04:50.719 are fair because there is some evidence that the condition 0:04:50.760 --> 0:04:53.760 is linked with aging in people, though she has yet 0:04:53.800 --> 0:04:56.960 to see studies done linking the condition to aging in dogs. 0:04:58.400 --> 0:05:01.640 For dogs with viral infections or those that can't otherwise 0:05:01.680 --> 0:05:04.279 be treated, the good news is is that if it's 0:05:04.320 --> 0:05:07.080 just a loss of smell, the dogs usually do pretty 0:05:07.080 --> 0:05:09.640 well with their lot in life, though of course, if 0:05:09.640 --> 0:05:12.360 their job utilizes that sense of smell, they may have 0:05:12.400 --> 0:05:16.440 to retire. And for pups with brain tumors or other 0:05:16.480 --> 0:05:21.000 brain related issues, the result is more complicated and unfortunately 0:05:21.200 --> 0:05:25.560 less cheery. More said, the problem with brain tumors is 0:05:25.600 --> 0:05:28.000 that they do get worse and tend to grow and 0:05:28.080 --> 0:05:31.479 cause other problems. Eventually, there is some palliatee of care 0:05:31.520 --> 0:05:34.400 we can provide. Sometimes we can use steroids to help 0:05:34.400 --> 0:05:37.040 with inflammation around the tumor, and that can be helpful 0:05:37.080 --> 0:05:39.279 for a period of time, but it's not a permanent 0:05:39.320 --> 0:05:42.400 fix from a quality of life standpoint. If they're having 0:05:42.440 --> 0:05:44.960 a lot of other problems, owners might need to consider 0:05:45.000 --> 0:05:48.520 putting their dog to sleep, but More said that is 0:05:48.600 --> 0:05:51.520 definitely a worst case scenario and that in the vast 0:05:51.600 --> 0:05:54.520 majority of dogs, anosmia is a conditioned that will not 0:05:54.640 --> 0:05:58.200 limit a dog's quality of life. She said, while it 0:05:58.279 --> 0:06:00.640 might cause a change in the dogs behave hear, the 0:06:00.640 --> 0:06:02.920 good news is that the most common cause of loss 0:06:02.920 --> 0:06:05.680 of smell and dogs is related to sinus infection, so 0:06:05.760 --> 0:06:13.440 most of those are going to be treatable problems. Today's 0:06:13.440 --> 0:06:15.600 episode was written by Patty res Mussin and produced by 0:06:15.640 --> 0:06:18.440 Tyler Clay. For more on listen lots of other curious topics, 0:06:18.520 --> 0:06:21.200 visit how stuff works dot com. Brain Stuff is production 0:06:21.240 --> 0:06:23.640 of I Heart Radio or more podcasts. My heart Radio 0:06:23.760 --> 0:06:26.360 visit the i heart Radio app, Apple Podcasts, or wherever 0:06:26.400 --> 0:06:27.719 you listen to your favorite shows.