It's dinner time, and you've just sat down to eat a nice steak and potato dinner. While eating, something bumps your leg, and you look down to see Fido sitting and staring at you excitedly as if he hasn't been fed in days! Yet, when you look over, you notice Fido's own bowl of kibble left untouched.
Why is it that Fido is so eager to smell and taste your meal, while seemingly unimpressed by his own? Why is it that some dogs will eat anything, including inedible objects (like your socks) without discretion, however the sight of a pill or even regular dog kibble turns his stomach?
The canine senses of smell and taste play a large factor in what your dog perceives as tasty, and knowing how these two senses work together can help solve the puzzle about why Fido is such a picky eater sometimes, but a canine vacuum at other times.
Your dog's anatomy can play a great part in how he determines what to eat, while the actual texture, taste and smell of food helps to play another. Combining knowledge of how both work can make dinner time, or even giving supplements or medications a much easier task, though it still may not save your socks.
Dogs have an amazing sense of smell, and it is considered one of their greatest traits. Their sense of smell has been used in a wide variety of jobs from tracking lost people in the wilderness, to finding drugs and explosives in areas where it could be dangerous.
Some dogs smell so well they can even be trained to help detect cancers that may be missed by conventional medical tests. While most dogs have a great sense of smell compared to humans, their own sense of smell can vary depending on the dog's age, breed and even sex!
A dog's sense of smell is thought to be 10-100,000 times more powerful than the human nose. This means dogs are able to distinguish even the smallest of smells that a human may never detect, such as a bit of sweat on a sock or even a piece of bacon in the back of the fridge!
Male dogs tend to have a greater sense of smell than females or older dogs, and this makes sense if you look at the dog's wild ancestors. It was the young males who would need to track scents to find territories or mates, while females and older animals tended to stay with the group or have less need to mate. Just like vision or hearing, smell declines as dogs age just like it does in people.
The dog's nasal cavities are made up of over 300 million olfactory receptors, a whopping 40x more than our human noses. The dog's uniquely shaped nose and nasal cavities also aid in smell by helping to mix new odors with the old when breathing, and to provide an area specifically for scent detection.
This means that when your dog sniffs the air, he is adding to the scent he's already caught, rather than washing it out with breathing like the human nose does. When inhaled air enters the dog's nose, it is split up in the nasal passageways, part of it heading to the lungs to provide oxygen from breathing, and part of it into the olfactory area of the nose located in the back of the nasal cavity.
This area then provides a greater ability to detect and process the smell as the receptors send signals to the brain about the smell, how strong it is, and where it may be located.
Dogs also have a special organ called the vomeronasal organ which is specialized in detecting hormones and pheromones in the body. This special detection center has its own area in the nose and connection to the brain, making it a useful addition to a dog's sense of smell.
Taste is often directly linked to smell, and many species will use what they are smelling to help enhance what they are tasting. If something smells bad, it is likely to taste bad too! Dogs are much better at smelling than tasting their food when compared to humans.
However, even if your dog relies on the smell of your socks rather than the taste before snacking on it, it doesn't mean his sense of taste isn't there.
Taste begins as one of the earliest senses for your dog, and helps him through puppyhood to determine what things are good to eat, and what may be harmful. While taste isn't as refined for dogs in puppyhood, it is present long before your dog even begins to see or hear the world.
Taste is done through the work of taste buds, found on various parts inside the mouth, mostly centered on the tongue. These taste buds are found on certain papillae which are the small bumps visible on the tongue when looking inside a dog's mouth.
While not all papillae types have taste buds, those that do are highly specialized in what they taste depending on their location on the tongue. Each taste bud can sense all tastes if the taste is strong enough, however different parts are slightly more sensitive to certain flavors when compared to others.
(Photo Courtesy of WikiVet)
Dogs have far less taste buds that humans, clocking in at only around 1700 taste buds compared to a human's 9000 (Cats have even fewer, with only about 470 taste buds to work with!) This means the dog has a more blunted sense of taste, and may not be as able to easily distinguish between subtle flavors.
Dogs are great at tasting sweet and bitter things like people, but do not seem to have taste buds for identifying salty foods like humans do. Their sense of taste regarding meats and fats is more refined than a human, likely due to their ancestors mainly meat diet in the wild (which means your dog likely wants your potato chips for their fat, not their salt.)
They can also detect sweet easily, but cannot detect saccharine or even some artificial sugars. The preference for naturally sweet tastes may again be a link back to the dog's ancestors, who would supplement their diet with fruits found in the wild.
The dog's great aversion to bitter tastes can also be beneficial for avoiding toxic foods, as well as be a problem when attempting to give medications or supplements that have a naturally bitter taste!
When studied in a laboratory, dogs showed a preference for certain tastes when eating. Meat-filled and sugary tasting foods were preferred over corn or grain-based foods when given a choice between the two.
Dogs also tend to prefer flavors that come with extra aroma, such as meats dipped in gravies, or canned foods that are still moist (and smelly) versus dry kibble. However, odor was not always the key factor in food choice, and dogs will still eat a food that is not strong-smelling if it provides the right taste and texture over one that is very smelly.
Outside of the laboratory, a dog's food preference varied greatly from dog to dog, and was closely linked to what the owner preferred, where the dog slept at night, and even how bonded dog and owner were!
Dogs also have a unique type of taste compared to humans, and that is the taste of water. The tip of the tongue, often used for helping a dog lap up water, is also home to several taste buds that are tuned for finding and tasting water. While these taste buds are always active, they become more sensitive after eating a meal, especially one with a high sugar or salt content.
When a bowl of food is placed down in front of your dog, several factors begin to work at once. Your dog may immediately begin sniffing, catching the scent of the meal if it is warm, wet, or has something special added to it.
He also takes a look at the meal when it's set down and his brain begins to send out receptors to tell him to drool and get ready for the meal. Once he begins to eat, his tongue goes into action, letting his brain know if the food is safe (not bitter) and tasty (fatty or sweet), and he then decides whether he will eat more or leave it behind.
After the meal is done, his tongue again helps him take a refreshing drink of water, aiding in digestion and stopping thirst. While each of these senses may have acted independently of each other, it is their combination that helped your dog determine if his meal was good or not.
What does this mean for you, the owner?
Eating is more than just taking a nutrient and putting it in the body to provide energy and care. Eating food has a lot to do with how it smells and tastes, but visual cues play a large part in eating as well.
Your dog is no different, and will often use visual cues in addition to smell and taste to determine if his food or supplement is up to snuff. Some dogs will even develop preferences for certain foods or flavors depending on their relationship with their owner, indicating there is much more at play than just taste or smell.
The same food day in and day out, pills that taste bad or have weird textures, or even the appearance of a person approaching with a medication or supplement can greatly affect your dog's desire to eat.
Luckily, a lot can be done to help encourage your dog to eat his food, even if he seems less than excited to do so.
As your dog ages, his sense of smell and taste begin to diminish, making him seem pickier about what he wants to eat. However, this change in diet preference that seemingly comes out of nowhere may be easily altered by changing what he eats and how he eats it.
Adding in foods or supplements that are more aromatic or pungent to the nose can help increase enjoyment of the meal by making it smell and taste better. Vitamin gravies, liquid supplements and oils can all help to increase the overall texture of food, and the additional added flavors make it more fun to eat. These additions also change the visual appearance of the food, which may increase its appeal.
Illness and age can play a large role in your dog's changing preferences and tastes too, so scheduling regular wellness checks with your vet is a must.
Your vet can help to determine if there is something else causing your dog's change in eating habits or behavior, and can help find supplements or medications that help him feel back to normal.
Your vet may also suggest a change in diet that also changes the flavor, texture or smell of his food, making it easier for him to recognize and enjoy it.
The answer to this very common question really depends on the type of pill being presented, but smell and taste can play a factor in why your dog doesn't like taking a supplement or medication in pill form.
Texture is an obvious issue, as the pill may feel funny in the mouth, and the experience of having it placed in your dog's mouth may be enough to make him think it's not good for him!
The bitter taste of some pills also plays a factor, as many pills are naturally bitter or coated with bitter substances.
Some owners can get away with adding pills to their dog's food, especially with less discerning pets such as young dogs, however for most people this isn't the case.
Pills can also be very smelly, or bitter, which can be very averse to dogs due to the fact that bitter is one of the key taste receptors they have.
To make it easier, finding a supplement that is palatable, or even one that doesn't come in pill form works great. Pills that are gel-caps or coated in tablet form may be easier to swallow, and more bitter pills can have food items such as a meatball or cheese wrapped around it to mask the taste and smell.
Adding a supplement in liquid form directly to the food completely bypasses the need to encourage your dog to eat a pill and can work great for dogs that are great at separating the pill from the meatball.
Every dog has his or her own taste and smell preferences, so finding a combination of things that work best for him is key. If your dog tends to dislike dry foods, offer a moist or semi-moist alternative, or even add in a gravy supplement for that extra flavor with a vitamin boost.
If your dog hates pills, try to find medications or supplements that can be given in liquid form safely, making it less of a hassle for both him and you during feeding times.
Mixing in additional things such as meatballs and oils can also provide a health benefit in addition to a flavor one, giving your dog a healthier coat, better skin, and an overall better life.
With the wide range of products available for pets these days, finding something that will make your dog's tail wag is easier than ever.
If you're looking for a quality liquid omega-3 supplement for your dog, check out our Wild Omega-3 for Dogs!
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Tyson, P. 2012. "Dogs' Dazzling Sense of Smell." Nova ScienceNOW, PBS. http://www.pbs.org/wgbh/nova/nature/dogs-sense-of-smell.html
Correa, J.E and J.H. Dwyer. 2011. 'The Dog's Sense of Smell." Alabama Cooperative Extension System, June 2011.
Coren, S. 2011. "How Good Is Your Dog's Sense of Taste?" Psychology Today; Canine Corner. 19 April 2011.
Houpt, K.A. and S.L. Smith. 1981. "Taste Preferences and Their Relation to Obesity in Dogs and Cats". Can Vet J. 1981 Apr; 22(4): 77–81.