Dogs are Carnivores, Right?

There is a great deal of confusion (and opinion) today regarding how to classify the domestic dog. Those who identify dogs as carnivores (meat-eating) animals tend to focus on the predatory nature of the dog’s closest cousin, the wolf. Conversely, those who are inclined to classify the dog as an omnivore (consumes both plants and meat) rely upon the dog’s scavenging nature and ability to consume and digest a wide variety of food types. So, which is it? And, perhaps more importantly why does what we call the dog, carnivore or omnivore, seem to matter so much to us? (And why do discussions about this issue seem to quickly escalate into shrillness, name-calling and spamming?)

That Escalated Quickly

First, let’s all just calm down. From a scientific viewpoint, it appears that some confusion may arise from the dual use of the term “carnivore”. This term is used as both a taxonomic classification and as a description of a species’ feeding behavior and nutrient needs. Both dogs and cats are classified within the taxonomic order of “Carnivora”, a diverse group of mammals that includes over 280 different species.


Some eat meat…..some don’t: While many of the species within Carnivora hunt and consume meat, not all are predatory or nutritionally carnivorous. The species within the order Carnivora vary considerably in the degree of dependency that they have upon a meat-based diet. For example, all of the cat species, including our domestic cat, Felis catus, are obligate carnivores. In contrast, bears and raccoons consume both plant and animal foods, while the Giant Panda subsists on a vegetarian diet. Therefore, while all of the species within the order called Carnivora can eat meat, their typical feeding behaviors exist along a broader spectrum, ranging from the obligate carnivores at one end to animals that are almost completely herbivorous at the other end.

So, where does the dog fall along this spectrum?

Cats vs Dogs: Let’s consider this question by comparing our two best animal friends, the dog and the cat. The label “obligate carnivore” (sometimes called true carnivore) means that the cat is incapable of surviving on a vegetarian diet and must have at least some meat (animal tissue) in its diet. This means that a diet that is composed of all plant materials cannot meet all of the cat’s essential nutrient needs. Specific nutrients that are problematic if Fluffy is fed a vegetarian diet include Vitamin A, a type of amino acid called taurine, and an essential fatty acid called arachidonic acid. All three of these nutrients are found in a form that cats can use in meat products and but are not found in plant foods. During evolution, cats either lost or never developed the ability to produce these nutrients in the body from the precursor forms that are found in plant foods.

The Adaptable Canine: In contrast, most of the canid species, including the domestic dog, are more generalist in their eating habits and subsequently in their nutrient needs. In the wild, wolves and coyotes exist as opportunistic predators, hunting and eating the type of prey that happens to be available. In addition to the flesh of their prey, wild canids readily consume viscera (stomach, intestines) which contain partially digested plant matter. Canid species also scavenge carrion and garbage and regularly consume fruits, berries, mushrooms, and a variety of other plant materials. Similar to its wild cousins, the domestic dog is a predatory species that also consumes plant foods and scavenges, and is capable of consuming and obtaining nutrition from a wide variety of food types.

Not only does the dog naturally choose a wider variety of foods to eat than do cats; the dog is capable of deriving needed nutrients from plant foods more efficiently than do cats. Let’s look at the three nutrients that we mentioned earlier; Vitamin A, taurine and arachidonic acid:Dogs vs cats

Finally, anatomically, dogs’ gastrointestinal tracts, from their mouths to their intestines, are consistent with other predatory species (i.e. meat-eating) that consume a varied diet. They have some ability to grind food (molars), and possess a small intestine that is longer in length (relative to body size) than that of obligate carnivores, but that is shorter in length than that of herbivorous species.

Altogether, the nutrient, metabolic, and anatomical characteristics of dogs place them on the omnivorous side of the spectrum within the wide range of species who hunt prey, scavenge, and consume plant foods

Carnivore Evidence

When we look at the evidence, we see that both nutritionally and taxonomically, the dog is best classified as an omnivore, an animal that consumes and derives nutrition from both animal and plant food sources. More specifically, the dog evolved from a species that made its living primarily through hunting and consuming prey but that also consumed whatever was available through scavenging. (Anyone who lives with a Golden Retriever is well acquainted with the scavenging part).

Time to drag out the box.



So, why is it that we read multiple websites, listen to certain “experts”  and talk to Joe next door (who happens to know a lot about dogs) and they insist that the dog is an (obligate) carnivore? Why are some folks so incredibly (and one might venture, obsessively) invested in this belief? Not to put too fine a point on it, many proponents of the “dog as carnivore” hold on to this conviction like a dog with a meaty bone. One may wonder, why is this distinction even important, except perhaps for academic interest?

My own opinion is that the keen interest that we see in recent years is caused by an unusual and somewhat unprecedented focus on a desire to “feed dogs naturally.” Oddly enough, prior to the development of commercially prepared dog foods in the early 1900’s, domestic dogs were fed naturally – they were fed scraps of human food… other words, they scavenged. So, we appear to have come full circle, with the only difference being that the fervent adherence to a mantra of “feeding dogs naturally” now focuses on the dog’s hunting and meat-eating history rather than on its equally significant existence as a proficient scavenger.

dog at table


Do dogs thrive on diets that include animal-based ingredients (i.e. meat, poultry, fish) – Yes, definitely (and especially if those ingredients are of high quality). Do dogs enjoy (and probably prefer) meat in their diets. Probably. Do dogs have a nutritional requirement for animal-based ingredients in their diets? No, they do not.

EXCERPTED FROM: Dog Food Logic: Making Smart Decisions for Your Dog in an Age of Too Many Choices, by Linda P. Case (click below for purchasing in formation).


Be a Citizen (Canine) Scientist!

Love dogs and interested in helping scientists to learn more about their behavior? If so, this study is for you! Graduate student Mie Kikuchi and Professor Daniel Mills of the University of Lincoln are conducting a survey study that examines cultural perceptions of canine aggression. Click the photo below to be a citizen scientist and participate in their study. (Note: The survey is quite detailed, so it is best to set aside at least 20 minutes to complete it).


NEW STUDY: Exploring cultural influences on the perception of human-directed aggressive behaviour in dogs

And please, feel welcome to share this link far-and-wide. The purpose of this study is to compare cultures, so the more participants, the stronger (and more interesting) will be the data! Enjoy!

Collect the Data


Got Gullet?

Innovative dog chews and treats are all the rage these days. Despite the claims of their sellers, most of these products are new twists on an old theme – taking the parts of food animals that we typically discard as inedible waste and turning them into expensive and often highly sought after dog treats. A few examples are bully sticks, pig ears, pig/cow hooves, cod skins, and the topic of this essay, beef gullets (esophagus) and tracheae. In addition to coming in a dried form as a chew, the entire neck regions of beef, lamb, chicken, turkey and other food animals are also included in some commercial and homemade raw diets.

The Question Is: Are gullets and tracheae (necks) safe for dogs to consume?

Beef Gullet Twist     Beef Gullet Chew       Beef Gullet

The Answer: Not if the thyroid gland came along for the ride.

Thyroid Gland 2

Quick Anatomy Lesson: The thyroid gland is a small organ that wraps around the upper portion of an animal’s trachea (wind pipe). When a cow is dissected for the production of human-grade meat, the trachea and esophagus are removed together as by-products. Although a law passed in 1986 prohibits their inclusion in human foods, these animal parts can be used in pet foods, which is exactly where they end up (along with other animal by-products that are deemed not for human consumption).

Thyroid Tissue in Your Dog’s Food: Thyroid tissue contains the hormone thyroxine, which will not be destroyed by the dog’s gastric acid or digestive enzymes. It is absorbed into the body and remains active. If a dog consumes enough thyroxine from the diet, an elevation in circulating thyroid hormone occurs and the dog develops hyperthyroidism (or more technically correct, thyroidtoxicosis). Some dogs develop elevated serum thyroxine but do not show clinical signs. Others develop signs that include weight loss, hyperactivity, excessive panting, and polydipsia/polyuria (increased drinking/urinating).

So, is this a problem that owners should be concerned with? Possibly; especially if you are feeding a raw diet.  Here is the evidence:


  • Twelve dogs fed raw diets: In 2012, German veterinarians at  Justus Liebig University reported elevated plasma thyroxine levels in dogs that were being fed either a raw diet or large amounts of fresh or dried beef gullet (1). Clinical signs of hyperthyroidism were reported in half of the dogs (6/12). Following diagnosis, seven owners immediately switched to a commercial dry food and stopped feeding gullet. Veterinary rechecks 2 weeks and 2 months later revealed that plasma thyroxine concentrations had returned to normal in all dogs and clinical signs had resolved. One owner did not change her dog’s diet. Repeated thyroid hormone tests showed elevated levels one and four months following diagnosis and the dog was experiencing chronic weight loss. At that point, the owner switched the dog to another food, clinical signs resolved and plasma thyroxine levels returned to normal.
  • Two more cases: Two cases were reported in 2014. In the first, an 11-month-old male Rottweiler was examined for signs of weight loss, excessive panting and increased blood thyroxine levels (2).  A complete diet history revealed that the dog was being fed a commercial raw diet. After switching the dog to a commercial dry food, signs resolved and blood thyroxine levels returned to normal. In a second case study, a two-year-old female Miniature Pinscher was examined for a failure to come into estrus (3). The dog was fed a homemade raw diet that included beef cuts from the head and neck region purchased from a local butcher shop. The dog had highly elevated serum thyroxine levels.  Changing the dog’s diet led to normalization of serum thyroxine and normal estrus cycles.
  • Raw foods and chews: Most recently, a study published in the Journal of the American Veterinary Medical Association reported findings of thyrotoxicosis in 14 dogs fed either a commercial raw diet or a variety of different chews or treats (4). All of the treats were some type of sliced or rolled jerky chew. Clinical signs resolved and thyroid hormone levels were normalized within four weeks of discontinuing the suspect products. The authors were able to obtain seven samples of the brands of food or treats that owners were feeding. When tested, all had elevated thyroxine levels when compared with control foods. The authors end with this statement: “The presence of high T4 concentrations in a variety of pet foods or treats sold under different labels suggests that the problem of thyroid tissue contamination of such items may be widespread and not confined to only a few products or manufacturers.”  (The authors also sent samples and identifying information about the products to the FDA for further investigation).

Take Away for Dog Folks: Okay, before raw feeders start flooding my blog with hate mail and sending in the trolls, let me state up front that these research results are by no means presented as a personal vendetta against feeding raw. 

No Trolls


Those of you who have read Dog Food Logic know that my position is that there are many approaches to feeding dogs healthfully, and a well-balanced, properly selected (and sourced) raw diet can be one of those approaches.

However, the evidence strongly suggests that the recent increase in diet-induced hyperthyroidism is likely a result of the increased popularity of both raw diets and of feeding unusual types of chews such as gullets and tracheae to dogs. At the very least, this set of case studies provides sufficient evidence that diet-induced hyperthyroidism is a health risk that warrants further study and investigation of the identified companies and brands.



Draggin’ out the ol’ box: Fear not. I do have a personal opinion on this matter (though I would be hesitant to go so far [yet] as to call it a vendetta). This has to do with data reported in the 2015 study, which were collected in the United States. In that study, all 14 of the dogs were being fed commercially prepared foods at the time of diagnosis. These were foods that the owners purchased from a company, trusting that the products would not only provide good nutrition to their dogs, but that they were SAFE. This should not be such a high bar to clear, yet it repeatedly seems to be for the pet food industry.

Here’s the thing: The knowledge that the presence of animal thyroid tissue in foods can cause hyperthyroidism is not new information. Outbreaks of diet-induced hyperthyroidism in people are well-documented and are the reason that “gullet trimming” as a source of ground beef was outlawed in the 1980’s. Yet, these tissues are still allowed in the foods that we feed to our companion animals. Why is this?

I maintain that pet owners should be able to easily discover exactly what is in the pet foods they feed to their dogs, including the source and quality of the product’s protein ingredients.  Yet this information is rarely provided and requests are often ignored, denied or responded to with evasive platitudes and assurances. Here’s a suggestion – Ask your pet food manufacturer if the food that you feed contains animal necks and if they guarantee that it does not contain thyroid tissue. Let me know what you hear back.

Request Denied

In a perfect world (and when I am queen), we will ban the inclusion of unsafe body parts in the foods that we feed to our canine family members. I know it is an outrageous suggestion, but a person can dream, cant’ she?

Got Gullet? Let’s hope not.

Cited References:

  1. Kohler B, Stengel C, Neiger R. Dietary hyperthyroidism in dogs. Journal of Small Animal Practice 2012; 523:182-184.
  2. Cornelissen S, De Roover K, Paepe D, Hesta M, Van der Meulen E, Daminet S. Dietary hyperthyroidism in a Rottweiler. Vlaams Diergeneeskundig Tijdschrift 2014; 83:306-311.
  3. Sontas BH, Schwendenwein I, Schafer-Somi S. Primary anestrus due to dietary hyperthyroidism in a Miniature Pinscher bitch. Canadian Veterinary Journal 2014; 55:781-785.
  4. Broome MR, Peterson ME, Kemppainen RJ, Parker VJ, Richter KP. Exogenous thyrotoxicosis in dogs attributable to consumption of all-meat commercial dog food or treats containing excessive thyroid hormone: 14 cases (2008-2013). Journal of the American Animal Hospital Association 2015; 246:105-111.






How Many Barks does a Nuisance Dog Make?

According to a paper that I read recently, nuisance barking is identified as a major, worldwide behavior problem that affects 1 in 3 dogs, is a frequent cause of neighbor disputes, and is a common cause of relinquishment of dogs by their owners to shelters and rescue groups (1).

Hmmm…. Nuisance barking.

So, once again, it is all about us. Because really, if we asked the dogs to tell us why they are barking, I would venture that the vast majority would NOT say: “Oh, because I want to be a nuisance“.

Rather (and I know you trainers and behaviorists are with me on this one), their reasons, in no particular order, are much more likely to be:

  1. I am bored because I spend too much time alone.
  2. I am stressed because I am uncomfortable being alone.
  3. I feel territorial around my home’s doors, windows, or yard.
  4. I am responding to noises in my neighborhood such as other dogs barking, vehicles approaching or people walking by.
  5. I am responding to the sight of people or other animals outside or near my home.

So, let me begin by saying, up front, that I was irritated by the title of this paper and the authors’ casual acceptance of the term nuisance barking. And yes, I know that the term can function as a way of classifying what people tell others and also how some animal control agencies handle barking complaints. However, if the place at which we begin is by classifying any barking that an owner (or neighbor) does not like in terms of human comfort and perspective, where exactly does that lead us regarding how we think about the dogs who are doing this barking? (Remember the Ben Franklin effect?) I would argue that the term nuisance barking itself is highly pejorative because once such a label is applied you now have a bad dog who needs correcting or a bark collar or relinquishment to a shelter. Because heavens, we certainly cannot live with a nuisance in our lives, can we now?

The good news is that once I got that rant out of my system, I went on to read an interesting study. Here is what they did:

The Study: Study participants were 25 dogs who had been identified by their owners as being guilty of the nefarious deed “nuisance barking.” The researchers were interested in determining the actual frequencies and durations of this type of barking and if there were clear factors in a dog’s life or behavior that were related. They studied this using a bark counter, a device that when mounted on a dog’s flat collar will record the duration, frequency and number of distinct barks throughout a pre-designated period. Each dog was fitted with a counter and barking was recorded continuously over a 7-day period. All of the owners also completed a questionnaire that provided information about themselves and their dog.

Results: A wide range of bark frequencies and durations were recorded.  For example, frequencies ranged from 10 to more than 500 barks in an hour. Dogs barked most frequently when their owner was away and the majority of the dogs in the sample (84 %) were confined to a yard or garden area when the owner was not at home. (Hmmm…..might these two things be related?).


Bark patterns throughout the day suggested that much of the barking was reactive – dogs were responding to one or more stimuli in their environment. When asked, many of the owners could readily identify the cause. The most frequently cited stimuli were the presence of people or other animals as they passed by the dog’s yard. (In other words, many owners already knew exactly what was causing their dog to bark).

Although few significant factors in dogs’ lives were found to influence barking (possibly because of the small sample size), the researchers did find a negative association between the amount of obedience training that a dog had received and degree of barking; dogs who had received training had lower barking frequencies than dogs who had not. A weak association was also found between the number of neighboring dogs and barking; dogs who lived near several other dogs were more likely to bark than dogs who did not. (And there’s a second environmental stimulus…..).

Take Away for Dog Folks: First, let’s forget the “nuisance” label. It is a red herring. Please stop using that word.

Keep Using

Second, it is significant that the owners of the dogs enrolled in this study were able to identify at least one clear underlying cause of their dog’s excessive barking (the presence of passersby near the dog’s yard). Neighboring dogs were apparently also a trigger for some dogs.

Huh. So, it really is not what some owners insist that it is.

Bark at Nothing

It seems to me we have more of an owner problem here than a dog problem. These data suggest that reactive barking is a common cause of excessive barking in dogs who are isolated in yards. And, lo and behold, there are several tried and true methods for reducing territorial or reactive barking in dogs (it really ain’t rocket science). These include:

  1. Reduce the time that the dog spends isolated in the yard.
  2. Train an alternative behavior (response substitution), such as coming away from the barrier (fence, property edge).
  3. Manage the behavior by preventing the dog’s ability to see/hear the triggering stimuli (privacy screens, bring the dog indoors).
  4. Increase the dog’s daily exercise, mental and emotional stimulation so that the dog spends less time isolated in the yard (if necessary hire a dog walker or use a reputable doggy day care).

I am back in my snit, it appears. It is my contention that dogs and their people are much better served if we stop using anthropocentric classifications for problem behaviors that label dogs as nuisances. Rather, as this study corroborates, dogs bark for reasons and often these reasons are something that we can remove, modify or manage. If we begin the discussion with “I have a nuisance dog who barks too much” we have all the further to go towards changing perspective and identifying the cause so that we can start helping both the dog and the owner.

Because dogs bark. And some dogs bark a lot. Maybe too much. (Just like people talk and some people certainly talk too much…..[you know these people, the nuisance talkers]. For those people in your life, you are on your own). For the dogs, I am with all of the trainers out there who start by finding out why the dog is barking, eliminating or modifying that cause, adding in a bit of training, exercising, and playing, with the ultimate goal of this:

Does not bark at nothing

Happy Training.

Cited Study: Raglus TI, Groef BD, Marston LC. Can bark counter collars and owner surveys help identify factors that relate to nuisance barking? A pilot study. Journal of Veterinary Behavior 2015; 10:204-209.



Go Ask Alice

We have a new puppy in the house. Alice is her name. She’s cute. Really cute.

Alice 3 Day 1


Of course, it is possible that I am a bit biased…….(nah…..she really is adorable, even now at 4 months….).

Ally 15 weeks


During the first few weeks that Ally was with our family, we could not go walking at our local park without being waylaid by other walkers who would swoop in (often without asking….sigh….) to meet the little puppy, hug the little puppy, and play with the little puppy. These interactions were replete with the high squeaky voice, nonsense words, and scrunched up kissy face that we all know (and sorta don’t love). Ally absorbs all of this attention like the little canine diva she is (though, she says that sometimes she would rather go chasing rabbits).

During these interludes, our three adult boys, Cooper, Chippy and Vinny, quietly offer sit-stays and hope to catch a bit of the fall-out. However, while handsome, friendly, and oh-so-smart, their obvious adult status just does not pull the same emotional heartstrings as Ally’s little puppy face seems to do.

Vinny, Cooper and Chip


Go ask Alice: So, I asked Alice if she knew why people on the trail swoon over her whilst ignoring her equally wonderful brothers. I thought she would know. She said without hesitation that it is because of her unbearable puppy cuteness (she added that all of the attention does tend to make her feel 10 feet tall).

Puppy narcissism aside, she is quite right. Research tells us so.

We like baby animals: Konrad Lorenz first explained this phenomenon using a concept that he termed “Kindchenschema”. This refers to a set of universal physical attributes of baby mammals that trigger unconscious affiliative (loving) and care-taking responses in adults.  These features include large eyes, a proportionately large and domed skull, shortened limbs and overall “pudgy features”. Following Lorenz, the theory that adult humans are naturally drawn to baby mammals has been studied in multiple variants, including with our favorite animal companion, the dog. For example, there is evidence that the infantilism that we see in toy breeds and in dogs with a brachycephalic (smushed nose) facial structure naturally mimic the appearance of puppies and so are highly attractive to many people (1,2). Other baby animal features that we see in some dogs such as floppy ears, pudgy bodies (natural or ahem, acquired), and short legs may be at work creating a canine Kindchenschema as well.

However, despite what Alice thinks, we know that our attraction to dogs is not all about puppies. People are also drawn to adult dogs for a variety of reasons. Two recent research studies have identified a few additional canine attributes that seem to attract us.

We pay attention to color and ears: A study published in 2008 reported that, similar to our tendencies with other people, humans readily assign personality traits to dogs based simply on their appearance (3). However, the study did not attempt to identify specific traits that might influence these perceptions. Recently, Jamie Fratkin and Suzanne Baker at James Madison University in Texas attempted to tease out some of these traits (4).  They selected two obvious features that differ among dogs; coat color (yellow vs. black) and ear type (floppy vs. prick). They manipulated the photographs of two dogs to show either a black or yellow coat color on one dog and floppy or prick (pointy) ears in the second dog. Study participants completed a questionnaire that rated each dog in terms of the Big Five personality traits; openness, conscientiousness, extraversion, agreeableness and emotional stability. Results: Both the color of a dog’s coat and the set of a dog’s ears influenced perceptions of personality. Participants perceived dogs with a yellow coat or floppy ears to be more agreeable and emotionally stable when compared to dogs with a black coat or prick ears, respectively. In addition, a dog with a yellow coat was rated higher in conscientiousness than a dog with a black coat and a dog with prick ears was rated as more extraverted than a dog with floppy ears. (Note: the questions that were used to score conscientiousness reflect dependability and self-discipline, which could be interpreted as signifying a dog who is well-behaved and obedient). At its most basic, this set of results tell us that perceptions of a dog’s personality are influenced by coat color and ear type in the absence of other information. More specifically, there is a tendency to perceive yellow dogs who have floppy ears more favorably than black dogs with pointy ears.

It really is (mostly) about us: Julie Hecht and Alexandra Horowitz at City University and Barnard College in New York expanded upon this theme and examined the potential influence that a wide range of physical features in dogs may have upon human perceptions (5). They altered 15 different physical features in each of a series of photographs of  28 adult, mix-breed dogs. Each altered photo was then paired with its original. The targeted features fell into one of four categories: juvenile traits (increased size or spacing of eyes and size of the head), human-like traits (presence of a smile, colored irises), size/symmetry attributes, and a single feature related to domestication (piebald coloring). The changes that they made were subtle enough that people were generally unaware of the difference between the two photographs. Study participants were presented with 80 paired images and were asked to simply select which dog they “liked the best”. Results: The physical traits that most strongly influenced “liking” preferences were the presence of a smile (open mouth, relaxed and retracted commissures) and having colored eye irises. Both of these features occur in human faces and are associated with positive (friendly) emotions. In other words, we tilt towards features that dogs and humans share and that mean similar things. Several, but not all, infantile traits also enhanced a dog’s attractiveness. These included having large eyes, increased spacing between the eyes, and smaller jowls. Conversely, the study found no influencing effects of any other facial features, nor for a dog’s size, symmetry, or presence of piebald coloring.



Take Away for Dog Folks: Taken together, these studies suggest that dog features that naturally attract us include the infantile (puppy) traits of large eyes, domed skulls and floppy ears, as well as yellow coats (when compared with black, anyway). Oh yeah, and we are also attracted to dogs who look similar to friendly people – they smile a lot and their eyes appear friendly and warm.  Clearly, years before this research was conducted, Disney knew all of this stuff. One needs only to take a look at Lady from the movie “Lady and the Tramp”, with her large, blue eyes, luxurious yellow coat, pert little (pushed in) puppy nose, and that lovely smile……

Lady and Tramp


Why is this information important?  Despite often knowing (or at least being informed of) the much greater importance of a dog’s personality and behavior as the criterion for selecting a pet, many people continue to choose a dog based upon physical appearance. (Ask any experienced shelter worker if you doubt this). People like what they like, and will choose accordingly. And, given the ubiquitous use of web sites and internet services to promote dog adoptions, the first thing that most people see of a dog or puppy who they are considering adopting is a photograph. These studies provide evidence that regardless of trying to convince adopters of the importance of meeting a dog in person, these photographs are an important influencer of adopters’ perceptions (correct or not) of canine personality. Thus shelters, rescue groups, and breeders can use this information not only when determining how to best photograph and present a dog on their websites, but also as they educate potential adopters regarding how a dog’s appearance may be subconsciously influencing them.

Black Dog Prick Ears


As for Alice, she says that white knights and red queens got nothin’ on her being a yellow dog with floppy ears and dark eyes. Seems she is set for life. Gotta go – Time to feed Ally…….

Ally Cooper Vinny Dinner


Cited Studies:

  1. Waller BM, Peirce K, Caeiro C, Scheider L, Burrows AM, McCune S, Kaminski J. Paedomorphic facial expressions give dogs a selective advantage. 2013; PLoS ONE 8(12):e826986.doi:10.1371/journal.pone.0092686.
  2. Golle J, Lisibach S, Mast FW, Lobmaier JS. Sweet puppies and cute babies: Perceptual adaptation to babyfacedness transfers across species. PLoS ONE 2013;8(3):e58248. doi:10:1371/journal.pone.0058248.
  3. Kwan VSY, Gosling Sd, John OP. Anthropomorphism as a special case of social perception: A cross-species social relations model analysis of humans and dogs. Social Cognition 2008; 26:129-142.
  4. Fratkin JL, Baker SC. The role of coat color and ear shape on the perception of personality in dogs. Anthrozoos 2013; 26:125-133.
  5. Hecht J, Horowitz A. Seeing dogs: Human preferences for dog physical attributes. Anthrozoos 2015; 28:153-163.

P.S. How many of the references to Alice’s namesake song did you catch? Find out here: Jefferson Airplane; White Rabbit


Weigh In On This

It is a fact that many pet dogs (more than 50 percent by several accounts) are overweight. I reviewed the current statistics regarding canine waistlines in an earlier blog, “Do you think I look fat in this collar“. In that essay, we learned that owners of overweight dogs have a tendency to incorrectly assess their dog’s body condition, almost always underestimating weight and seeing a dog who is overweight as being ideal.  Kinda like the portly fellow and his mirror below.

Fat Man


One suggestion to reduce this epidemic of perceptual disconnect is to post canine body condition score (BCS) charts in veterinary clinics. The reasoning is that veterinarians will use these charts to educate their clients and help owners to get a better handle on Rover’s weight problems. Of course, such charts are only helpful if the veterinarian chooses to use them and then actually discusses Rover’s weight with the client.  Therefore, as a follow-up question to this research, one might ask, “Do veterinarians regularly access the body condition of dogs during routine visits?” Lucky for us, a group of researchers recently asked exactly that question.

The Study: Private veterinary practices in England, Wales, Scotland and Northern Ireland were recruited to participate.  Data from over 49,000 patient visit records were collected and were examined for the inclusion of a weight diagnosis (overweight or obese). When a diagnosis was found in the record, the dog was matched with a control dog using the criteria of age, sex, neuter status, breed and of course, weight. However, the control dog did not have a recorded diagnosis of being overweight. This research design is called a “case controlled study” and it allowed the researchers to examine various factors that influence whether or not a veterinarian will focus on a dog’s weight status during a routine veterinary visit.

Results: Of the 49,488 dogs whose records were examined, a notation for being overweight was found in only 671 cases (1.4 % of the dogs). Body condition score was recorded in less than 25 percent of patients. When comparisons were made between the dogs whose record showed a diagnosis of being overweight with their matched controls for which no diagnosis was made, only one health-related factor was found to influence whether or not a veterinarian discussed (and recorded) a dog’s overweight status. This was the diagnosis of osteoarthritis or lameness as a presenting problem. The researchers speculated that veterinarians would naturally include a thorough weight assessment in dogs with signs of arthritis, given the well documented association between overweight conditions and mobility problems in dogs. No other individual health problem or lifestyle factor was associated with a discussion of weight status during veterinary consultations.

Dr Says I am Fat


Take Away for Dog Folks

Since data from multiple sources tell us that upwards of 50 percent of pet dogs are overweight or obese, it appears that, much like dog owners, veterinarians are markedly under-diagnosing obesity in their canine patients. It also appears that including BCS charts in examining rooms is not the answer, since veterinarians recorded a body condition score for less than 25 % of their patients. It is important to note that an important limitation of this study was that it was able to examine only written patient records and had no way to review the actual conversations that had occurred between veterinarians and their clients. It is certainly possible that in at least some cases, Fluffy’s weight problem was discussed during the visit, but not recorded in her file. However, even if the methodology missed a lot of diagnoses,  1.4 % is still a heck of a long way from 50 %. It is reasonable to assume that a substantial number of the 49,000 dogs in this sample group were overweight but had not been diagnosed as such during their routine veterinary visits.

If veterinarians are not stepping up (as much as they should) and calling Rover rotund, who can? Well the good news is that in this day and age there are many other pet professionals who work with dogs on a daily basis, interact regularly and positively with a multitude of dog owners, and who are completely capable of assessing body condition and weight status in dogs. So, trainers, doggy day care owners, independent pet supply store owners, shelter/rescue professionals, dog walkers, and pet sitters – consider this your call to arms! Help out your clients by educating them regarding good feeding and exercise habits for their dogs, carry a BCS chart with you or post one in your business (better yet, have a scale handy), and gently but firmly encourage your owners to prevent overweight conditions in their dogs to keep them healthy and happy throughout life.

Mocking Corgi


Cited Study: Rolph NC, Noble PJM, German AJ. How often do primary care veterinarians record the overweight status of dogs? Journal of Nutritional Science, 2014; 3:e58;1-5.

Fear Itself

Last year, on the drive home from our annual vacation in Bar Harbor, Maine, our 11-year-old Brittany, Vinny suddenly and inexplicable awoke from a sound sleep and began to tremble, pant, pace, and obsessively lick at the sides of his travel crate. When I crawled back over the seat to find out what was wrong, Vinny’s eyes were “squinty” and he avoided looking at me as he continued to lick and pant. Mike immediately pulled over to a rest area and we got Vinny out of the car. As soon as he was on the ground and moving about, Vinny relaxed, looked at us calmly, gave each of us a nice Brittany hug, and off we went for a little walk. Perplexed, we thought that maybe he had to eliminate (nope, no urgency there), was feeling carsick (no signs), or had a bad dream (who knows?). Within less than a minute, our boy was his typical happy self, showing no signs at all of distress. We loaded all of the dogs back into the car and Vinny continued the journey home with no further incident. We still are not sure what triggered this odd stress episode in our boy. He has had one (equally perplexing) recurrence since, continues to be healthy and happy, and we continue to monitor him carefully both at home and when he is traveling with us.

Vinny Loves Bar Harbor


Recognizing Stress and Fear

It is important for dog owners to recognize and respond to signs of stress and fear in our dogs. If we are sensitive to their emotional states and are accurate in our interpretations, we can respond appropriately to situations in which a dog is uncomfortable, stressed, or frightened. Because nonspecific signs of stress can be the first signs of illness or injury, attending to these promptly may help us to get our dogs the medical attention that they need before conditions worsen or escalate into an emergency. It is well-known that perceiving and understanding the emotions of others is a basic human social skill. We use these perceptions on a daily basis when we interact with other people – family members, friends, and even strangers. Interestingly, while most of us are capable on some level of reading the emotional states of other humans, studies have shown that these abilities vary tremendously among individuals. Similarly, because many share our lives with dogs, it follows that we use these same skills when interpreting the emotions of our canine friends.



Studying Perceptions

However, until recently, the accuracy of our perceptions of dogs’ emotional states had not been studied. Two research studies examined the cues that we use and our levels of accuracy when we perceive fear and stress in our canine companions.

Study 1: The first was conducted by researchers in the Department of Psychology at Columbia University in New York (1). The study team produced a series of video clips of dogs and embedded them in an on-line survey. Participants viewed the videos and then were asked to classify each dog’s emotional state using one of five possible descriptors (angry, fearful, happy, sad, or neutral). The first four of these are called “primary emotions” and were selected because research has supported the existence of these emotions in dogs and other animals. Although the study participants had 5 choices, the videos in the study only showed dogs demonstrating two possible emotions, either happiness or fear. All of the videos had been pre-categorized into the two emotion categories by a panel of dog behavior experts prior to the start of the study. After identifying each dog’s emotion, participants were asked to describe the specific features of the dog that they felt led them to their conclusion. For example, if a person classified a dog as showing happiness, she might say that the dog’s facial expression, ear set, and wagging tail were important features that conveyed this state to her. Last, the participants were asked to rate the level of difficulty that they experienced while attempting to interpret the emotions of each dog and to provide an estimate of overall confidence in their accuracy.

Results: Over 2000 people completed the survey and were divided into four dog experience categories based upon their dog ownership and professional histories. These were non-owners, owners, dog professionals with less than 10 years of experience, and professionals with more than 10 years of experience. It was somewhat surprising to find that the vast majority of people who completed the survey, more than 90 percent, correctly identified happy dogs in the video clips, regardless of the person’s level of dog experience. This means that most people, even those who have never owned a dog, could look at a happy dog and see…..a happy dog! This is good news.

Happy Face 3


However, when it came to recognizing fear in dogs, the news was not quite so positive. While more than 70 percent of dog professionals correctly identified the fearful dogs, this proportion dropped to 60 percent of dog owners, and to only 35 percent of non-owners. Put another way, this means that 40 percent of dog owners and 65 percent of non-owners were unable to correctly identify signs of fear and stress in an unfamiliar dog. Moreover, a substantial number of the non-owners (17 percent, or about one in six people) misclassified a fearful dog as a happy dog. This statistic is especially troubling, given the potential dangerous outcome of such mistakes. A person who approaches a dog who they believe to be friendly but who in effect is fearful, will at the very least increase the dog’s fear and distress and could potentially cause a defensive response in the dog, leading to a snap or bite. The features of the dogs that participants used to make their decisions also varied with experience level. A person’s tendency to focus on a dog’s facial features (eyes, mouth, ears) increased significantly along with experience. Inexperienced participants used primarily the dog’s tail and body posture to inform them about the dog’s emotional state. Conversely, more experienced people identified both facial expressions and body postures as important features when assessing a dog.

Interestingly, but perhaps not surprisingly, the results of this study are consistent with studies of human abilities to perceive and interpret the expression of emotions in other people. We are generally more sensitive to and more accurate at interpreting happy facial expressions in other people than we are when responding to fearful expressions. Moreover, while social experience seems to have little effect upon our responses to happy faces (we show a proficiency to do this at a very young age), having varied and extensive social experience is an important factor in determining our success at perceiving fear and stress in other people. In dogs, this study tells us that dog-related training and experience enhance our tendency to pay attention to dogs’ facial expressions along with their body postures and enhances our ability to correctly perceive fear.

Study 2: While the first study provided a general test of how people perceive fear in unfamiliar dogs, the second examined the ability of dog owners to recognize signs of stress in their own dogs (2). This study was conducted by researchers at the University of Pisa in Italy with a group of almost 1200 dog owners recruited through veterinary clinics. Participants first completed a questionnaire in which they were asked about stress in dogs and its potential health and behavioral consequences. They then identified what they believed to be signs of stress in dogs and estimated the level of stress in their own dog.

Results: More than half of the owners (60 %) were found to have a clear understanding of what stress is and how it can affect a dog’s emotional state and health. However, about 20 percent of owners (one in five) believed that experiencing stress had no negative physical or emotional consequences on dogs. (In other words, while they agreed that it occurred, they thought it was no big deal). The behaviors that owners most frequently identified as reflecting stress in their dog included trembling, whining/crying, excessive barking, and panting. In contrast, very few owners identified more subtle behaviors such as avoiding eye contact, turning away, yawning, nose licking, or yawning as signs of stress in dogs. Those owners who self-reported as being highly concerned with their dog’s stress level were more likely to identify these less obvious signs as important. Overall though, owners tended to miss many of the facial expressions (squinty eyes, avoiding eye contact, changes to ear set, retracted commissures) that most trainers immediately look for when they are assessing a dog’s stress level. Like the first study, this suggests that it is these more subtle facial cues of stress and fear that may be missed if a person is only paying attention to the more obvious body posture signs.

Take Away for Dog Folks

These two studies provide complementary information about the behavior cues that people pay attention to when attempting to decipher a dog’s emotional state. The first showed that even inexperienced people were able to correctly identify a dog who is happy and relaxed. However, perceptions of fear were strongly correlated to how much prior experience a person has had with dogs. As experience level increased, not only were people more likely to be correct, but they also were more likely to pay attention to a dog’s facial expressions than were people who did not spend much time with dogs. We also learned that dog owners are more likely to focus attention on their dog’s body posture, vocalizations and movements than on the more subtle signs of stress that involve a dog’s facial expressions and eyes.

Why it matters: Accurately recognizing fear and stress in dogs is an important skill set to have. Understanding our own dog’s emotional state allows us to respond by helping him out of situations that cause fear and reducing or eliminating triggers of stress when they are under our control. For trainers and behaviorists, working with owners who are sensitive to their dog’s stress response promotes the development of a more effective training and management plan. On a societal level we all benefit from a universal understanding of the behaviors, body postures and facial expressions that convey happiness versus fear or stress in dogs. Correctly interpreting a dog’s behavior is always enhanced by attending to both body posture and facial expressions. However, interpretation of dogs’ facial expressions may not come naturally to many people. This knowledge emphasizes the importance of teaching the subtleties of canine facial expressions in training classes, behavior education courses, and bite prevention programs. Moreover, the statistic suggesting that one in five owners do not consider the effects of stress in their dogs to be of negative consequence tells us that education is also needed regarding the health and welfare impacts of stress and fear on our dogs’ well-being and quality of life.

Here at home, Mike and I are still uncertain about what caused Vinny’s acute stress response during our vacation trip. As Vinny has aged he has become somewhat more sound sensitive, which is not unusual in senior dogs. However, even though we responded quickly at the time and he apparently recovered, we did not learn enough from the episode to determine a possible underlying cause. Perhaps we will never know. Regardless, I do know that paying attention to all of Vinny’s signs – body language, facial expressions, and eyes, will help me to understand him, care for him, and love him as best we can.

Vinny and Cooper Aunt Betty Pond Run


Cited References

  1. Wan M, Bolger N, Champagne FA. (2012) Human perception of fear in dogs varies according to experience with dogs. PLoS ONE 7(12): e51775. doi: 10.1371/journal.pone.0051775
  2. Mariti C, Gazzano A, Moore JL, Baragli P, Chelli L, Sighieri C. (2012) Perception of dogs’ stress by their owners. Journal of Veterinary Behavior 7:213-219.

NOTE: A version of this article was published in the December 2014 issue of Whole Dog Journal and is also included in my newest book, Beware the Straw Man: The Science Dog Explores Dog Training Fact & Fiction“.