Talking Turkey

I grew up with a story-book grandmother. She was my mother’s mom, “Nana” to my sister and me. As required of all perfect grandmothers, Nana was a great cook and regularly expressed her love through sumptuous meals and comfort foods. Although she did not actually reside “over the valley and through the woods”, her home was definitely the place to be on all food-oriented holidays, including birthdays (cake!), Christmas (cookies!), and of course, the ultimate All-American food holiday, Thanksgiving (turkey!). Like many Americans on this day, my family gorged ourselves with all that Nana placed on her over-loaded dining room table – mashed potatoes, stuffing, butternut squash, warm rolls, salads, corn casserole, and of course, the mandatory roasted turkey. Following this annual feast, my sister and I would fall into food-induced stupors, sleeping off our over-indulgence for several hours before rousting ourselves to eat one more piece of pie.

Tgiving Food Coma

THE BASSET FAMILY ENJOYS THEIR ANNUAL FOOD COMA

A number of years later I learned that my post-feast drowsiness was (presumed to be) caused by to a specific nutrient in turkey. This theory, first put forth by a nutritionist, proposed that turkey meat contains unusually high levels of the amino acid, tryptophan. Once absorbed, tryptophan is used by the body to produce serotonin (a neurotransmitter) and melatonin (a hormone). The neurological pathway through which serotonin works has anti-anxiety and calming effects and melatonin helps to induce feelings of drowsiness (i.e. enhances sleep). Therefore, the theory goes, after consuming a high-protein meal, in particular one that is high in tryptophan, the body’s production of melatonin and serotonin increase, which in turn cause drowsiness, reduced anxiety and a calm state of mind. Presto – the post-turkey coma!

Tryptophan Cartoon

Tryptophan Takes Off: The tryptophan/turkey theory became so popular and widespread in the early 1980’s that nutrient supplement companies decided to by-pass the turkey part of the equation altogether and began producing and selling tryptophan supplements (L-tryptophan). These were initially promoted as sleep aids and to reduce signs of anxiety. However, as is the nature of these things, the promoted benefits of L-tryptophan rapidly expanded to include, among other things, claims that it would enhance athletic performance, cure facial pain, prevent premenstrual syndrome, and enhance attention in children with attention deficit-hyperactivity disorder. (My personal favorite was the promotion of L-tryptophan as a treatment for Tourette’s syndrome). L-tryptophan enjoyed a robust reputation as the nutrient for “all that ails ye’” until 1989, when it was found to be responsible for causing eosinophilia-myalgia in more than 5000 people, killing at least 37 and permanently disabling hundreds. The US Food and Drug Administration quickly banned its import and sale as a supplement. Although the problem was eventually traced to a contaminant in a supplement that was imported from a Japanese supply company (and not the L-tryptophan itself), the ban remained in effect until 2009. Today, L-tryptophan is once again available as a nutrient supplement but it has never regained its earlier popularity in the human supplements world.

What About Dogs? Given its history, it is odd that L-tryptophan was largely ignored by the dog world until a research paper published in 2000 suggested that feeding supplemental L-tryptophan might reduce dominance-related or territorial aggression in dogs (1).The researchers also studied dogs with problem excitability and hyperactivity, but found no effect of L-tryptophan on either of these behaviors. However, the paper led to the belief that tryptophan supplementation was an effective calming aid in dogs (which it definitely did not show in the study) and as an aid in reducing problem aggression. Today, a range of L-tryptophan supplements are marketed for reducing anxiety and inducing calmness in dogs. Interestingly, none are pure L-tryptophan, but rather also include other agents that are purported to have a calming effect on dogs, such as chamomile flower, passion flower, valerian root, or ginger.

What Does the Science Say? Does eating turkey or taking an L-tryptophan supplement reduce anxiety and induce calmness? And, can it be used as an effective nutrient supplement to reduce anxiety-related problem behaviors in dogs?

 The Turkey Myth: It is a myth that consuming turkey induces drowsiness or reduces anxiety. The theory fails on several counts. First, turkey meat does not actually contain a uniquely high level of tryptophan. The amount of tryptophan it contains is similar to that found in other meats and is only half of the concentration found in some plant-source proteins, such as soy. (Do you get sleepy after gorging on tofu?).

Trypt Levels in Foods

TRYPTOPHAN LEVELS IN FOODS

Second, researchers have shown that the amount of tryptophan that is consumed after a normal high-protein meal, even one that contains a lot of tryptophan, does not come close to being high enough to cause significant changes in serotonin levels in the blood or in the synapses of neurons, where it matters the most. Third, to be converted into serotonin (and eventually into melatonin) tryptophan that is carried in the bloodstream following a meal must cross the blood-brain barrier and enter the brain. This barrier is quite selective and only accepts a certain number of amino acids of each type. Tryptophan is a very large molecule and competes with several other similar types of amino acids to make it across the barrier. Following a meal, especially if the meal is high in protein, tryptophan does increase in the blood and is pounding at the blood-barrier door for access. However, it is also competing with other amino acids that are also at high levels (turkey contains all of ‘em). As a result, very limited amounts of tryptophan make it into the brain for conversion following a meal that includes lots of other nutrients.

        Why So Sleepy? The real explanation for the drowsiness and euphoria that we all feel following a great turkey dinner at Nana’s house is more likely to be caused by simply eating too much (which leads to reduced blood flow and oxygen to the brain as your body diverts resources to the mighty job at hand of digestion), imbibing in a bit of holiday (alcoholic) cheer, and possibly, eating a lot of high-carbohydrate foods such as potatoes, yams, and breads, which lead to a relatively wider fluctuation in circulating insulin levels. Whatever the cause, don’t blame the turkey or the tryptophan.

Eat too much  Blame Tryptophan                                        THE TRUE CAUSES OF TURKEY COMA

Tryptophan Flying Solo:  The erroneous focus upon turkey did have some positive consequences in that it led to a closer look at tryptophan’s potential impact upon mental states and behavior when provided as a supplement. As a serotonin precursor, tryptophan (and its metabolite 5-hydroxytryptophan or 5-HTP) has been studied as either a replacement or an adjunct therapy for serotonin reuptake inhibitors (SRRIs), medications that are commonly used to treat depression in people and are sometimes prescribed as treatment for anxiety-related behaviors in dogs. Although limited work has been conducted regarding the effects of tryptophan supplementation in dogs, several informative papers did follow the initial dog study of 2000:

            Tryptophan and anxiety: Researchers at Wageningen University in the Netherlands studied a group of 138 privately owned dogs with anxiety-related behavior problems (2). Study design: Half of the dogs were fed a standard dog food (control) and half were fed the same food, formulated to contain supplemental L-tryptophan. Neither the owners nor the researchers were privy to dogs’ assigned groups. In other words, this was a “double-blind, placebo-controlled study” (see my book “Dog Food Logic” for more about studies), the Gold Standard of research designs. Dogs were fed their assigned diet for 8 weeks, during which time the owners recorded behavior changes. At the end of the study, the researchers also performed a set of behavior evaluations to assess the dogs. Results: Although blood tryptophan levels increased significantly (by 37 %) in the dogs that were fed supplemental tryptophan, neither the owners nor the researchers observed any difference in behavior between the supplemented group of dogs and the control dogs. There were moderate changes in behavior over time in all of the dogs, but this change was attributed to a placebo effect. Overall, supplementation with L-tryptophan demonstrated no anxiety-reducing effects in the dogs enrolled in this study.

        Tryptophan and abnormal-repetitive behaviors: This was another double-blind and placebo-controlled study (3). In addition, the researchers used a “cross-over” design in which half of the dogs are first fed the control and the other half are first fed the test diet for a period of time and are then all switched to the alternate diet for a second study period. This is a well-accepted study design that is helpful when a researcher has limited number of subjects and that helps to control for the placebo effect. A group of 29 dogs was identified, each presenting with a form of abnormal-repetitive behavior. These were: circling, anxiety-related lick granuloma, light chasing/shadow staring, or stool eating. (Note: One might question the inclusion of stool-eating in this study, since many pet professionals consider eating feces to be a form of scavenging behavior that is normal and common in the domestic dog). Dogs were treated for 2-week periods and the frequencies of their abnormal behaviors were recorded daily. Results: The researchers reported no effect of supplemental L-tryptophan on the frequency or intensity of abnormal-repetitive behaviors. Although the owners reported slight improvements over time, this occurred both when dogs were receiving the supplemental tryptophan and while they were eating the control diet (there is the insidious placebo effect again). Limitations of this study were that it was very short-term and it targeted uncommon behavior problems that are notoriously resistant to treatment. Still, this study did not provide any evidence to support a use of tryptophan supplementation for repetitive behavior problems in dogs. (So, to all you folks who live with poop-eaters – sorry, no easy answer here with L-tryptophan).

          Tryptophan-enhanced diet and anxiety: Dogs with anxiety-related behavior problems were fed either a control food or the same food supplemented with L-tryptophan plus alpha-casozepine, a small peptide that originates from milk protein (4). This was a single-blind, cross-over study in which only dog owners were blinded to treatments. All of the dogs were first fed the control diet for 8 weeks and were all then switched to the test diet for a second 8-week period. Because the treatment group always followed the control in this study design, it is impossible to distinguish between a placebo effect and an actual diet effect in this study. (Note: This is a serious research design flaw that the study authors mention only briefly). Results: A small reduction in owner-scored anxiety-related behaviors was found for four of the five identified anxiety problems. However, in all of the cases, initial severity of the problems were rated as very low (~1 to 1.5 on a five-point scale in which a score of 0 denoted an absence of the problem and a score of 5 denoted its highest severity), and the change in score was numerically very small, though statistically significant. This is not surprising since there is not very much wiggle room between a score of 1 and a score of 0. Finally, given that the food was supplemented with both L-tryptophan and casozepine, conclusions cannot be made specifically about L-tryptophan.

Take-Away for Dog Folks

First, forget the turkey. While it can be a high-quality meat to feed to dogs (especially if you are selecting a food that includes human-grade meats or are cooking fresh for your dog), as a protein source turkey contains no more tryptophan than any other dietary protein. Feeding turkey to your dog will not promote calmness (unless of course, you allow him to stuff himself silly along with the rest of the family on Thanksgiving Day). Second, keep your skeptic cap firmly in place when considering the effectiveness of supplemental L-tryptophan or a tryptophan-enriched food as a treatment for anxiety-related problems. The early study in 2000 reported a modest effect in dogs with dominance-related aggression or territorial behaviors but found no effect in treating hyperactivity. Subsequently, two placebo-controlled studies reported no effect at all and the single study that reported a small degree of behavior change could not discount the possibility of a placebo effect.

Human nature encourages us to gravitate toward easy fixes for things that ail our dogs. Hearing about a nutrient supplement or a specially formulated food that proclaims to reduce anxiety and calm fearful dogs is powerful stuff for dog owners who are desperate to help their dogs. These types of claims are especially appealing because anxiety problems can have a terrible impact on a dog’s quality of life and are often challenging to treat using the standard (and proven) approach of behavior modification. An additional risk that must be mentioned regarding our inclination to gravitate toward unverified nutritional “cures” is that well-established approaches such as behavior modification may be postponed or rejected by an owner who instead opts for the supplement, wasting precious time that could actually help a dog in need. Until we have stronger scientific evidence that demonstrates a role for L-tryptophan in changing problem behavior in our dogs, my recommendation is to enjoy the turkey, but train the dog.

Cited References:

  1.  DeNapoli JS, Dodman NH, Shuster L, et al. Effect of dietary protein content and tryptophan supplementation on dominance aggression, territorial aggression, and hyperactivity in dogs. J Amer Vet Med Assoc 2000; 217:504-508
  2. Bosch G, Beerda B, Beynen AC, et al. Dietary tryptophan supplementation in privately owned mildly anxious dogs. Appl Anim Behav Sci2009; 121:197-205
  3. Kaulfuss P, Hintze S, Wurbel H. Effect of tryptophan as a dietary supplement on dogs with abnormal-repetitive behaviours. Abstract. J Vet Behav 2009; 4:97.
  4. Kato M, Miyaji K, Ohtani N, Ohta M. Effects of prescription diet on dealing with stressful situations and performance of anxiety-related behaviors in privately owned anxious dogs. J Vet Behav 2012;7:21-26.

*A version of this article was published in the July 2014 issue of Whole Dog Journal.

You Barkin’ At Me?

I have a ring tone on my mobile phone that I really like. It barks. Five barks (bark-bark-bark-bark-bark) for each ring. It is a real dog’s voice, not a person fake-barking in that annoying way that certain people feel compelled to do when they see a dog. (Really, what is that about anyway?). Earlier this week, my phone started barking while I was getting my hair cut. My hairdresser laughed and asked if any of my  dogs react to the barking phone. I told him that no, they always ignore it, which is strange, since it is definitely the recording of a real dog bark.

To which he replied “Maybe the dog isn’t saying anything”.

Barking Cartoon

Maybe. But recent research suggests that dogs do have something to say and that other dogs are often quite interested in hearing what that is.

Background information: The auditory (vocal) signals that animals make often have important communication functions and possess context-specific information. This means that a sound may be conveying information about several things at once. For example, an alarm call may vary in subtle but detectable ways depending on the location of the threat and how dangerous it is. Vocalizations may also be important signals that allow animals to recognize and identify one another. Indeed, this ability has been demonstrated in a wide range of species of birds, mammals, and even amphibians.

So, what about dogs? Previous research has shown that like many other animals, the sounds that dogs make are varied and highly context-specific and that humans, especially those who are experienced with dogs, are quite capable of distinguishing between different types of dog barks (1,2). However, while it is easy to test a human’s response to dog barks (we can just ask them questions), it is more difficult to ask dogs what they are learning when they listen to the vocalizations of other dogs.

dog-and-dog-statue-cap

Difficult, but not impossible. A group of ethologists at the Eotvos Lorand University in Hungary recently designed two clever experiments in which they were able to ask dogs – What are other dogs saying to you when they bark?

The technique: The reseachers used an approach called “habituation-dishabituation” to measure dogs’ reactions to the recorded sounds of barking.  The technique works like this. The dogs were first allowed to habituate to recordings of a particular dog who was barking in a particular situation. Habituation was measured by recording the number of seconds that the listening dog continued to show interest in a dog/situation combination over time. A decrease in attention was interpreted to indicate habituation. A dog would stop reacting to the sound as it lost significance much in the way we habituate to the sound of our air conditioner kicking on because it is heard repeatedly through the day.  Then (here is the clever part), the researchers changed either the identity of the dog who was barking or the context of the bark. The introduction of something that is new or unexpected should cause dishabituation, but only if the listener notices the change. (For example, if your air conditioner suddenly started making a rattling noise, you would dishabituate to it and take notice, right?).  In this case, if the listening dog responded by suddenly increasing his/her attention to the recording, this means that the dog noticed the change and so was capable of distinguishing between different dogs and/or different causes of barking. If on the other hand, the change did not cause a change in the listener dog’s behavior, such a result would indicate that the dog had habituated to the general sounds of a dog barking and was not gleaning any specific information from the recordings. The group of investigators published two studies with dogs using this technique.

Study 1: The researchers recorded the barks from five adult dogs in two different contexts; either in response to an unfamiliar person approaching a garden area or when left alone, tied to a tree in a park (3). They then brought 30 other dogs into the lab and played the recordings from a hidden recorder, first allowing habituation to a particular dog/situation and then, for the dishabituation test, changing either the dog or the cause.  Results: The subject dogs consistently showed an increase in interest to the recordings in response to both a change in identity of the dog who was barking and also in response to a change in the cause of barking. These results suggest that dogs are capable of differentiating who is barking when they hear another dog and what the dog is barking about. What this study design could not tell us however, is what exact type of information (if any) the dogs were gleaning from the recorded dogs or if they were capable of identifying a known individual by his or her bark.

Study 2: This time around, the researchers asked the question – Do dogs recognize the barks of other dogs who they know and do they react to what their friends are barking about (4)?  A group of 16 dogs, all living in multiple-dog homes, were tested. The dogs were tested in their own homes (so had an attachment to the context) and they listened to a hidden recording of either an unfamiliar dog or of one of their housemate dogs (who was not present at the time, because that would just be weird). The two situations were the same – barking when left alone or barking at an unfamiliar person approaching the yard’s fence. Each dog’s reactions were videotaped to allow careful analysis of any changes in behavior while listening to the recordings. Results: The dogs showed specific behaviors that depended upon who the barker was (friend or stranger) and upon what was causing the barking (isolation or territorial). Upon hearing a recording of their housemate, dogs would move toward the house where the dog was expected to be. Conversely, they moved toward the yard’s gate when they heard the sound of an unfamiliar dog barking at a stranger. The listener dogs also barked most frequently in response to the “stranger coming” recordings, regardless of whether the bark came from their housemate or a stranger. The researchers concluded that dogs appeared to be able to identify other dogs “by bark” and that they also obtained information about a bark’s cause, simply by listening, in the absence of other cues such as the barking dog’s body language or facial expressions.

Take Away for Dog Folks:  The results of this study instruct us (once again) to take care with  our assumptions when working with dogs. While it should be naturally obvious that dogs are proficient at  recognizing and understanding one another via vocalizations and that a great deal of information is conveyed via barking (and I would bet a few of you were shaking your heads whilst reading and muttering, “well, no kiddin'”), we often do not behave as though we actually believe this to be true. Here is what I mean.

Crazy Barking

Dog owners, trainers and behaviorists frequently classify barking in dogs as a problem behavior. If we don’t like it, if it annoys us, if we deem it excessive or an attention-seeking behavior, then it immediately gets dumped into the “behavior problem” bin. Well, granted, excessive barking can be annoying, can pose a community nuisance, and as a recurrent behavior may need some modifying. (Believe me, I understand vocal dogs – I live with a Toller). However, perhaps as humans we have become so intolerant of dogs barking that we may occasionally stop seeing it for the important communication tool that it is in our efforts to stop it.

soapbox

UP ON MY SOAP BOX AGAIN!

Up on the ol’ box: Moreover, we may often get it wrong.  Barking that is classified as problematic because it is thought to be “attention-seeking” could in actuality be a legitimate bid for affection from a chronically neglected dog. Or barks that an owner is instructed to ignore so as to “extinguish the behavior” may in fact be conveying true distress. (See “Is it time for the extinction of extinction?” for more about this). Is it also not possible that a dog who shows alarm barking truly has something to be alarmed about? While I am not suggesting that we should allow all dogs, at all times, to bark to their little heart’s delight (though, that is certainly what Chippy my Toller is going for), I am advocating that just as we accept body postures, facial expressions, eye contact, elimination patterns, and touch (tactile signals) as important forms of communication in our dogs, so too we should accept (and decriminalize) barking.

As trainers and behaviorists, perhaps it is time to dial back the trend towards classifying any barking that an owner does not like as “attention seeking”, “demand”, or “nuisance” barking, and reclassify it as a normal communication pattern that warrants understanding of the cause and as needed, modification. As the very chatty species that we are, we should be sensitive to and wary of any training approach or behavior modification program whose goal is to produce a completely silent dog.

As for my barking phone, I will continue to enjoy it, even if the dog is speaking nonsense. And Chippy the Toller, of course, says “Bark on, man, bark on”.

Chip Jan 2012

WE TOLLERS HAVE A LOT TO SAY

Cited Studies:

  1. Pongracz P, Molna Cs, Miklosi A, Csanyi V. Human listeners are able to classify dog barks recorded in differenct situations. Journal of Comparative Psychology 2005; 119:228-240.
  2. Pongracz P, Molna Cs, Miklosi A, Csanyi V. Acoustic parameters of dog barks carry emotional information for humans. Applied Animal Behavior Science 2006; 100:228-240.
  3. Molnar C,OPongracz P, Farage T, Doka A, Miklosi A. Dogs discriminate between barks: The effect of context and identity of the caller. Behavioural Processes 2009; 82:198-201.
  4. Pongracz P, Szabo E, Kis A, Peter A, Miklosi A. More than noise? Field investigations of intraspecific acoustic communication in dogs (Canis familiaris). Applied Animal Bahavioual Science 2014: In Press.

Lend a Helping Paw

Dogs are highly social beings who express their social nature in a variety of ways. They desire companionship with others and readily integrate into our human families and lives. Most of our dogs love to play and to learn new things and enjoy spending time together going for walks, a ride in the car or simply hanging out for a cuddle on the couch. Given the choice, most dogs prefer to share their days with their human family rather than alone and many also have strong social relationships (friendships) with other dogs or even with members of other species.

dogandparrot

Canine Friendships Come in Many Forms

Although not yet studied thoroughly, dogs may also exhibit certain types of “prosocial” behavior. These are spontaneous actions that are intended to help another individual in some way, usually with no obvious benefit to the helper. Psychologists have defined four general categories of prosocial behavior. These are comforting, sharing, informing and helping. At least anecdotally, comforting is something that dogs seem to excel at.  Many dog owners relate that their dog is very empathic, seems to know when they are sad or are having a bad day, and often stays close at hand to provide comfort and love. Behaviors related to sharing may be less common, but certainly many of us have known a dog or two who readily shares his toys, bed or food with others.

sharing stick      sharing bed  Sharing water           Sharing (?) a stick                         Sharing a bed                       Sharing a drink

What about the most complex prosocial behavior – Helping? There is no doubt that dogs can be successfully trained to help humans. Examples abound and include dogs who aid the disabled, move or protect livestock, find illicit contraband, and perform in search and rescue operations. The number and variety of trained skills that dogs use to help us are both vast and impressive. However, prosocial helping is a bit different because this type of aid occurs spontaneously with little or no former training. Prosocial helping behavior is intrinsically (internally) motivated by empathy or a sense of community and occurs without an obvious or anticipated reward to the performer.

For dogs, this form of helping is considered to be a relatively complex social behavior because it requires two things. First, the dog must understand the goal of the person who is in need. Second, the dog must be motivated to help the person to achieve that goal. For example, in the case of helping a person to find something, the dog has to understand that something is hidden/lost and that the owner is searching for it (and wants it) and must also have a desire (i.e. be motivated ) to help the person to find the object. It is this second component of helping, the intrinsic or internal motivation to help others, that a group of researchers at the Max Planck Institute for Evolutionary Anthropology in Germany recently studied. They asked the question: “Are dogs inclined to lend a helping paw?

The Study: The researchers conducted a series of four experiments to determine whether dogs would come to the aid of a person who was attempting to enter another room to retrieve a set of keys. The same scenario was used in each experiment, but the identity of the person and the way in which the person communicated his goal to the dog were varied.

  • Door opening behavior: Prior to the start of the experiments, dogs were trained to open a plexiglass door that entered into a small room (i.e. the target room) by hitting a button that was positioned on the ground in front of the door. Dogs and people could easily see into the target room. The dogs were trained to hit the button and open the door via shaping and positive reinforcement (food treats). This training took place several days prior to the actual experiment and only dogs who successfully learned to hit the button were included in the experiment. The behavior used for opening the door was purposely trained without a cue, to ensure that the dogs learned how to open the door but were not trained to respond to a specific command to do so.
  • Experimental conditions: During each experiment, a researcher or the dog’s owner communicated to the dog their desire to enter the target room by one of several means. These included either pushing on the door, reaching for the door, pointing at the button, using gaze (either into the room alone or alternating between the room and the dog), talking (general terms), commanding the dog, or a combination of spontaneous (natural) communicative gestures. In all conditions, the goal that the owner or experimenter was attempting to communicate to the dog was that they needed to enter the target room to retrieve the keys that were on the floor. (Note: Keys were purposely used as an object that would have no or little value to the dogs, thus ensuring that their inclination to help was not motivated by a desire to retrieve a toy or to obtain food). In each experiment, the control was a person who sat near the dog but did not communicate a desire to enter the target room.

Results: Dogs were highly likely to help in two primary conditions. These were either when the person used pointing gestures that were directed toward the button that opened the door or when the person used a variety of “natural” communication gestures simultaneously such as gesturing, talking, gazing and pointing to express their goal. Interestingly, the person’s identity did not influence the dog’s response. Dogs were as likely to help a stranger as they were to help their owner. The researchers concluded that the dogs in this study were highly motivated to help a human when the person’s goal was clearly communicated using either a common communication signal (pointing) or a variety of naturally selected gestures in combination. They suggested that an absence of helping behavior in dogs may be more likely occur when dogs do not understand the person’s goal,  rather than due to the lack of an intrinsic desire to be of aid.

Helping Dog

Will your dog lend a helping paw?

Take Away for Dog Folks:

  • It’s all about communication: The results of this study emphasize some important issues about how we communicate with dogs. When isolated gestures or verbal commands were used to attempt to communicate the person’s goals, dogs did not perform well. Give this a try and see how unnatural it feels. Point or gaze at something near your dog but do not use any additional words, body language or gaze. Does your dog respond? (Mine did not – they just looked at me like I was a crazy person). Conversely, when owners were instructed to just “communicate naturally” with their dog using a myriad of signals, the dogs’ understanding and success increased dramatically. While this difference is not all that surprising, it is important information for trainers and owners to keep in mind. Simply issuing a command or gesturing stiffly won’t cut the mustard with most dogs. Similar to communicating with the humans in our lives, effective communication with dogs includes a variety of  simultaneously delivered verbal and non-verbal signals – signals that can be messy and complex and difficult to define, but ultimately that are most successful at getting the message across.
  • Imperative versus informative gestures:  Researchers who study dog cognition are interested in whether dogs are capable of understanding human communicative gestures as being informative (i.e. providing helpful information) rather than interpreting them only as imperative (i.e. as a command to do something). This is an important distinction because while it is well-known that dogs can be trained to perform quite complex tasks and respond to trained cues, there is not that much scientific evidence showing us that dogs regularly use human behavior as information (although anecdotal evidence of this certainly abounds). The results of this study, and a few others before it, suggest that dogs are capable of perceiving certain human gestures, such as pointing and gazing, as information and that they may subsequently use that information to act (and help).
  • Empathy – Yep, they got it. There is no doubt that dogs are of great help to us, in a myriad of ways. We train dogs to aid the disabled, protect us, find lost children, and comfort the ill. However, that type of helping (while noteworthy and admirable in its own right) differs qualitatively from spontaneous helping in which the dog perceives a need and, presumably motivated by empathy, reacts by providing aid. It is this latter form of helping that was tested in this study. The cleverly designed set of experiments showed that when the goal of the person was clearly communicated to the dogs, many immediately helped the experimenter – and did so even when there was no obvious reward available to them. While all dog lovers know in our heart of hearts that our dogs express love, concern, and even compassion for others, here is some science showing us that contrary to the beliefs of an ever declining few, humans do not have a corner on the empathy market. Once understanding is achieved, our dogs are willing to  help us – even with something as mundane as helping someone to enter a room to retrieve some keys! (Just think about what they may be capable of when we really need their help). Have some fun – Test your own dog and find out if he is willing to lend you a helping paw!
Helping Dog

What does your dog help you with?

Reference: Brauer J, Schonefeld K, Call J. When do dogs help humans? Applied Animal Behaviour Science 2013;148:138-149.

I Yawn for Your Love

Vinny, my Brittany, yawns a lot. He yawns first thing in the morning when he rises, in the evening when he is tired, and many times in between. We notice this because Vinny emits an adorable little squeaky sound whenever he launches a particularly wide and emotive yawn. We also know that Vinny seems to be highly susceptible to contagious yawning. If Mike or I or one of the other dogs yawn when we are close by, Vinny immediately joins in.

Vinny Yawns

YAWNING VINNY

Recently, I was delighted to find a series of research studies examining the phenomenon of yawning in dogs and their people. The primary objectives of these studies were to determine if dog yawning, traditionally believed to be a mild stress response, is in actuality (or additionally) a reflection of social contagion and empathy.

Yawning Dog Wolfhound

I FEEL YOUR YAWN……

Background information: Contagious yawning is a well-established phenomenon in humans. Not only are most of us easily induced to open wide when someone nearby emits a yawn, there is evidence that even just hearing a yawn noise or watching others yawning on a video are sufficient to trigger a yawn response. (Indeed, I would venture that simply reading the previous two sentences, in which the word “yawn” occurs six times, caused more than a few readers to……yawn).

There are several theories that attempt to explain why yawning is socially contagious. At the simplest cognitive level, group yawning may just reflect unconscious mimicry, a form of priming (see “The Steve Series” for a discussion of priming in dogs). This is the most parsimonious view as it does not require emotional attachment between the yawner and the “yawnee” and does not require the ability to empathize (or have a “theory of mind”). Alternate theories place contagious yawning somewhat higher on the social cognition scale and suggest that it represents an involuntary empathic response. In other words, people yawn when others do because they feel the same (i.e. empathize). According to this view, people should be more likely to yawn in response to others who they know well and have an emotional bond with than when they are with unfamiliar yawners. In recent years, data show that this is indeed true. Additional studies showing that people who score highly on psychological tests of empathy are more susceptible to contagious yawning have tipped the evidence scale towards the empathy theory (at least for people).

What about dogs? Although spontaneous yawning occurs in many mammals, contagious yawning has only been described in humans, chimpanzees, and in recent years – in dogs.  Studies with dogs have asked three primary types of questions:

  • Do dogs exhibit cross-species contagious yawning? In other words, does seeing a human yawn increase the likelihood that a dog will respond with a yawn?
  • If it does occur, is it a type of empathic response? Are dogs more likely to yawn in response to someone they know and share an emotional bond with than they are in response to a stranger? If so, does contagious yawning have a communication function?
  • And, a related question that is of interest to most trainers – May contagious (or spontaneous) yawning be simply a stress response that occurs during times of low or moderate anxiety? If so, is there a contagious component to it?

The Studies: The first published study of dog yawns appeared in 2008 in a paper entitled “Dogs Catch Human Yawns” (1). The researchers studied a group of 29 dogs and found that 21 of the dogs (72 %) demonstrated contagious yawning when sitting near an unfamiliar (yawning) person. The control group (eye contact plus non-yawning mouth movements) elicited zero yawns. This was pretty impressive, seeing that rates reported in humans range between 45 and 60 % and chimps come in at a paltry 33%. Although this study demonstrated yawn contagion, the design of the study did not allow the researchers to determine if the dogs were yawning as an expression of empathy or as a stress/anxiety response. Other researchers decided to study this further:

  • Nope, ain’t happenin': A 2011 study compared yawn rates in dogs who were exposed to the yawns of either their owner, a stranger, or another dog (2). They also compared pet dogs living in homes with rescue dogs living in a shelter. Although they saw a bit of yawning (~ 26 percent of dogs), the rates did not differ significantly from control rates for any of these conditions. These researchers concluded that they found no evidence for empathy-based contagious yawning in dogs.
  •  Listen……there it is! This study took a different approach; they recorded the sound of yawning in 29 dog owners and then played these recordings back to each owner’s respective dog (3). The dogs were also exposed to the yawn sounds of an unfamiliar person and to familiar/unfamiliar non-yawn sounds (controls). Hearing the sound of yawning caused a response in 41 percent of the dogs and the sound of a familiar yawn elicited significantly more yawns than did the sound of an unfamiliar yawn. (Additional analysis of the data collected in this study suggested that stress-induced yawning was not an underlying cause of dog yawning, lending support for the social (empathy-based) theory [4]).
  • I yawn for you: This 2013 study was specifically designed to test whether contagious yawning in dogs was a result of stress or if it reflected an empathic response (5). The researchers monitored dogs’ heart rates during each condition as a measure of physiological stress. Testing 25 dogs, they found that dogs did indeed demonstrate contagious yawning, that dogs yawned significantly more frequently in response to their owner than in response to an unfamiliar person, and that heart rates did not increase significantly during the experiment. Their results lend support to the hypothesis that dogs show contagious yawning with humans and that this behavior is socially modulated (i.e. empathy-based) rather than  stress-based.
  • But wait……do dogs also stress yawn contagiously? The most recent study, published in 2014, shows just how complicated the dog yawning story may actually be (6). Changing things up a bit, this group of researchers worked with a group of 60 shelter dogs and exposed them to a yawning (unfamiliar) experimenter. They measured both yawn responses and salivary cortisol levels, which like heart rate are expected to rise during periods of physiological stress.  Contagious yawning in the shelter dogs occurred in only 12 (20 %) of the dogs, but interestingly, it was those dogs (the yawners) whose cortisol levels were increased. These results suggest that stress yawns can also occur contagiously.
Stress Yawn

STRESS YAWN?

Take Away for Dog Folks: Taken together, the results of these studies suggest that yawning in dogs may be context-specific, having different functions depending upon setting and situation. Similar to several other species, dogs do appear to yawn during periods of mild stress, possibly as a displacement behavior. In these cases, the yawn is accompanied by other communicative signs of tension such as a lowered body posture, panting, pacing or whining. [Note: While some posit that dogs yawn as a signal to "calm" other dogs or people, there is no empirical evidence to support this belief]. The data in these studies suggest that a stress yawn may also occur “contagiously” when faced with an unknown person in a new setting, perhaps as a result of the person (or her yawns) causing an increase in tension in the dog. Conversely, contagious yawning that occurs in a relaxed and happy dog, typically in response to a familiar person, may signify a type of social communication that reveals some level of empathic response. In those cases, what exactly is being communicated (“I’m tired too” or “This TV show is boring; can we please turn Lassie on”, or “Let’s go for ice cream!”) is still open to debate. 

Cited References:

  1. Joly-Mascheroni RM, Senju A, Shephred AJ. Dogs catch human yawns. Biology Letters 2008;4:446-448.
  2. O’Hara SJ, Reeve AV. A test of the yawning contagion and emotional connectedness hypothesis in dogs, Canis familiaris. Animal Behaviour 2011;81:335-340.
  3. Silva K, Bessa J, Sousa L. Auditory contagious yawning in domestic dogs (Canis familiaris): first evidence for social modulation. Animal Cognition 2012;15:721-724.
  4. Silva K, Bessa J, deSousa L. Familiarity-connected or stress-based contagious yawning in domestic dogs (Canis familiaris)? Some additional data. Animal Cognition 2013;16:1007-1009.
  5. Romero T, Konno A, Hasegawa T. Familiarity bias and physiological responses in contagious yawning by dogs support link to empathy. PLoS ONE 2013:8(8):e71365.
  6. Buttner AP, Strasser R. Contagious yawning, social cognition, and arousal: An investigation of the processes underlying shelter dogs’ responses to human yawns. Animal Cognition 2014;17:95-104

Hey, Teacher! Leave Those Dogs Alone!

It is a fairly common practice among dog trainers who teach group classes to “borrow” one of their student’s dogs to demonstrate a training technique or learning concept. Opinions of this practice vary. Proponents say that it helps owners to observe their own dog being handled by an instructor or responding to someone else, while opponents argue that it can appear as instructor grandstanding, may embarrass the owner, and can confuse or even frighten the dog.  First, make note that this is not an issue that I feel so strongly about that I would march on Washington about it or wear a sandwich board in protest on a busy street corner. (Although I can come up with a few catchy sign phrases, were I so inclined).

funny-political-signs-13

“Hey Teacher! Leave Those Dogs Alone!”

However, I do place myself firmly in the “don’t take my students’ dogs to demo” camp. My reasons are not as much to do with embarrassing the owner (which admittedly can happen), as they are concerned with the dog’s welfare and comfort level and with  being consistent regarding my own personal beliefs about our relationships with dogs.

Here is what I mean: When out and about with my own dogs, I neither enjoy nor tolerate a stranger approaching us to say hello to my dogs, and then instead of greeting them politely and spending some time getting to know them through petting and chit-chat with me, the person instead barks out some command. Although these commands are usually benign (sit or “shake” seem to be  popular), they grate on me and annoy my dogs.  And of course, if my dogs do not instantly snap-to and comply, the person barks again, more loudly. Fun times.

Not only is such human behavior unpleasant to be around, I see no reason at all that my dogs should be arbitrarily required to listen to someone who they do not know and have absolutely no relationship with. Therefore, since I personally do not want other people deciding that my dogs are required to listen to them, why would I foist such a practice upon my own training school students and their dogs? Instead, the policy at my training school is for instructors to use our own dogs for demonstration purposes or if our dogs are not present for the class, we enlist the aid of the invisible dog, “Muffin” (who always listens).

What do the dogs think? I have not yet found any research that examines how dog owners feel about having someone else train, work with or command their dog. However, a study was recently published that asked how dogs feel about this (1).

The Study:  The researchers were interested in finding out if the presence or absence of a dog’s owner and the familiarity of a tester influences a dog’s behavior and performance during various types of cognitive testing. They were particularly interested in teasing out context-specific effects. In other words, do dogs react differently to familiar versus unfamiliar handlers depending on what you are asking of them or the situation in which they find themselves? Here is how they studied this:

  • Dogs and Handlers: A group of 20 adult, well socialized dogs and their owners participated in the study. In addition, each owner selected a friend or relative who their dog knew well (familiar person). The unfamiliar person was one of the female researchers, who had not previously met any of the dogs. (Because gender has been shown to have a significant effect upon behavior, this factor was controlled in this study by enrolling only female owners and friends).
  • Tests: A set of eight behavior tests was administered to each dog. Some of the tests measured the dog’s response to separation from the owner or other stressors, and others examined the dog’s response to obedience commands or handling (see the complete paper for details). In addition, two locations were used; an unfamiliar, indoor testing area and a familiar outdoor area. Each dog was tested by their owner, the familiar person, and the unfamiliar person. (Note: Because of several logistical constraints, this was not a completely balanced study design).

Results: Both the human handler’s familiarity and the context (type of test and setting) significantly influenced dogs’ behavior and response to commands. While the dogs consistently discriminated between their owner and the unfamiliar person and always preferred the owner, discrimination between the owner and the familiar person was affected by context. Here are the highlights:

  • Choice and confidence: Unsurprisingly, when allowed to choose between their owner and the other two handlers, dogs consistently showed clear preference for their owner. They also showed a greater tendency to interact with others when the owner was present, a phenomenon that has been observed in other studies and is referred to as the “secure base” effect. It appears that owners provide their dog with a feeling of security and enhanced confidence, which in turn encourages the dog to explore new situations and people. In the absence of the owner, dogs’ behaviors tended to be more inhibited.
  • Stressful situations: Dogs distinguished strongly between their owner and the other two testers (familiar and unfamiliar) in situations that were stressful, such as separation or the approach of a threatening human. Most compelling? The presence of the friend could not sufficiently substitute for the presence of the owner in any of these settings.
  • Play: Although most of the dogs would play with all three testers, they spent more time playing with their owner and orienting to the toy (ball) that the owner was holding than they did with either the familiar or unfamiliar tester. During play, the dogs did not show a preference for the familiar over the unfamiliar person, but reacted similarly to both.
  • Response to commands: Overall, dogs responded most consistently to the owner rather than the other testers for basic commands of come, sit and down. However, the average time that it took for dogs to respond to commands (called latency) was not different between owners and the familiar person. In contrast, dogs took significantly longer to respond to commands if they were given by the unfamiliar person.
Comfort Base

We are our dog’s comfort base

Take Away for Dog Folks: Given these results, let’s return to the question of whether or not it is helpful for an instructor to take a student’s dog from them to demonstrate a technique or to help them to train their dog. Certainly in many cases, an instructor becomes well-known to the dogs in his or her class and is recognized by most of the dogs as a friend. (This is especially true if the instructor regularly carries yummy treats in her training pouch and is very generous with those treats). Still, even knowing this, the results of this study suggest that dogs perform best when they have their owner close at hand to act as their secure base. When a bit stressed (as group classes can often be), it really does not matter if the person who takes the dog is familiar or not (or is a better trainer than the owner). Dogs still prefer to be with and respond best to their owner. So, if you are in the habit of taking others’ dogs from them to demonstrate or train, keep in mind that even if you are more skilled, even if you can train the behavior faster, and even if the dog performs well for you, this may not be the dog’s preference. And if we are in the business of building strong bonds between dogs and their people, this may be something to consider.  

Reference: Kerepesi A, Doka A, Miklosi A. Dogs and their human companions: The effect of familiarity on dog-human interactions. Behavioural Processes 2014; In Press.

Its All Rock-and-Roll to Me

When training my dogs, I always have music playing. And, truth-be-told, my personal tastes gravitate neither to easy-listening nor to high-brow classical music. Rather, I am a rock n’ roll gal, all the way home. On a given day, my dogs and I may be training agility to The Who, retrieving to Stevie Ray Vaughan, and practicing tricks to Ray Lamontagne. On days that my feminist freak flag is flying, Janis Joplin, Melissa Etheridge, and Alanis Morissette are on deck. My dogs of course are accustomed to this and (I hope) share my love of all that rocks.

Chip in particular seems to enjoy early Beatles:

So, considering my habit of  training to music, I was interested to find a recent study that examined the effects of music on dog behavior. In this case, rather than looking at dogs rocking out during agility training, the researchers were studying dogs housed in a kennel environment (1).

The Study:  A kennel setting can be highly stressful for dogs, particularly those who are homeless and residing in a shelter. In attempts to improve their welfare, researchers have studied a variety of strategies for reducing kennel-induced anxiety. These include providing interactive toys, promoting social interactions with people, increasing opportunities for exercise and play, and adding various types of environmental enrichment. Sensory stimulation is a form of environmental enrichment that may use visual, olfactory, or auditory stimuli to induce a more calm and relaxed state. For example, there is ample evidence that listening to classical music has mood-enhancing effects in people and a small amount of evidence showing similar responses in dogs (2). However, the effects of different genres of music have not been studied at all in dogs. For example, are they rockers like me or more into muzak? Recently, a group of researchers at Colorado State University asked the questions “Can exposure to music during periods of kenneling reduce stress and anxiety in dogs?” and “Do dogs react differently to different types of music?”

PetsMusic_main_0319

Can music be calming for sheltered dogs?

Dogs and music selections: Two groups of dogs were studied; adult Dachshund rescue dogs (n = 34) and owned dogs (multiple breeds) housed in the same facility for short-term boarding (n = 83). The kennel was a traditional design consisting of a long row of indoor rectangular enclosures that faced each other on each side of a center concrete walkway. Dogs were housed either singularly or in pairs and were walked on-lead outdoors twice daily. Three types of music were tested: classical (4 selections), heavy metal (3 selections), and a commercial dog relaxation track (modified classical music).  Music selections were played in a randomized sequence for 45-minute periods, with each period followed by 15 minutes of no music. The control was a 45-minute period with no music. Dogs were observed by a single individual for 5-minute increments throughout each music or control period. Recorded behaviors included the dogs’ type of activity, time spent vocalizing, and the presence/absence of body shaking.

Results: Rescue dogs and boarding dogs did not differ in their response to music, nor did the type of housing (single or paired) influence response. Both the presence/absence of music and the type of music influenced dogs’ behavior and apparent stress levels:

  • Activity: Dogs spent significantly more time sleeping when listening to classical music than when they were listening to either heavy metal, the commercial relaxation music, or no music at all. Neither heavy metal nor the commercial relaxation track significantly affected sleep time or activity level. (Contrary to speculation, listening to heavy metal music did not induce hyperactivity; parents of teens, take note).
  • Vocalizations: Both genre and song selection influenced vocalizations, although these effects were not dramatic. For example, dogs were silent for 95 % of the 45-minute period while listening to the classical selection, Moonlight Sonata. By comparison, they were silent 86 % of the time when no music was playing. In general, the kenneled dogs barked between 5 and 15 % of the time and were slightly more inclined to bark when no music was playing.
  • Body shaking: Dogs spent dramatically more time shaking when listening to heavy metal music (38 to 71 %of the time, depending on the selection) than when listening to classical music (0.5 to 2.8 % of the time), the commercial selection (0.5 %) or no music at all (1.2 %). One particular heavy metal song caused dogs to shake the most –  a whopping 71 % of the time. To put this in perspective, this means that, on average, dogs were showing nervous body shaking for 32 of the 45 minutes that they listened to this song.

Take Away for Dog Folks: Music appears to significantly influence the behavior of kenneled dogs, and this includes both rescue (homeless) dogs and dogs who are owned and are being temporarily boarded. This study provides some helpful information for trainers, owners, and shelter/rescue professionals:

  1. Classical music apparently induces sleepiness in dogs (glad to learn that I am not alone in that respect). A response of increased relaxation/sleep is definitely a good thing, since anxious/stressed dogs are generally more active and spend less time relaxing than do non-stressed dogs.
  2. Heavy metal music is to be avoided with dogs as it appears to have induced stress, possibly severe stress, in kenneled dogs (again, good to learn, can’t stand the stuff, myself).
  3. Save your pennies: The commercial selection that was tested in this study was marketed by the company selling it as  being “psychoacoustically arranged” (whatever that means) to promote dog relaxation. However, this music had minimal effects on stress-related behavior in this study, performing less well than classical music that was not psycho-babble arranged. While the underlying cause for this difference was not clear, this result illustrates the risk of  taking a bit of research (classical music is calming to humans) and applying it to dogs by marketing and selling a track of “relaxation music” without adequate supporting research.

The point should not be lost that the relaxation benefits of listening to classical music that are documented in humans (and now, documented also in dogs) may be of benefit to both shelter dogs and to the folks who care for them. So, even if you are an ol’ time rock-n-roller, like me, consider at the very least, that classical music may be the way to go when you are working with group-housed dogs living in stressful environments.

Chip Jan 2012

Chip says…But when it comes to training time with your mom, “Rock On Dude, Rock On“!

References:

  1. Kogan LR, Schoenfeld-Tacher R, Simon AA. Behavioral effects of auditory stimulation on kenneled dogs. Journal of Veterinary Behavior 2012; 7:268-275.
  2. Wells DL, Graham L, Hepper PG. The influence of auditory stimulation on the behavior of dogs housed in a rescue shelter. Animal Welfare 2002;11:385-393.

 

 

 

 

Fear Factor

Experiencing fear is not pleasant. Any human will tell you this. As one of our most basic emotions, fear functions as a rapid-fire means of communicating to our bodies  “DANGER, DANGER – GET AWAY NOW!!”

Running from Tella Tubbies

OF COURSE, WE ALL TEND TO FEAR DIFFERENT THINGS….

As a physiological state, fear is associated with a set of bodily changes that are decidedly uncomfortable.  Respiration and pulse increase, we become hyper-vigilant of our surroundings, our hearts pound, and we may experience a strong inclination to flee (especially considering that Tella Tubbies run really fast despite their portly dimensions).

Dogs who experience fear exhibit the same physiological signs as humans and most likely also suffer the same unpleasant emotional state. Common fears/anxieties in dogs include separation anxiety, fear of unfamiliar people or dogs, and sensitivity to  thunder or loud noises. When these problems persist over long periods of time, they will definitely reduce a dog’s quality of life and can negatively affect the relationship between the dog and his or her owner. In addition, long-term exposure to stress may affect dogs’ physical health and longevity.

Background: There  is evidence in humans and in laboratory species that experiencing prolonged periods of stress and anxiety  increase an individual’s susceptibility to disease and risk of premature death (1-3). A possible underlying cause for this effect may be chronic activation of the hypothalamic-pituitary-adrenal [HPA] axis, which is part of the body’s natural defense against physical and psychological stressors. It is the HPA system that is responsible for elevated levels of cortisol, that well-known hormone that prepares one’s body for flight or fight. Although cortisol is highly effective in the short-term, prolonged exposure to high circulating levels is associated with a number of chronic health problems, such as hypertension, insulin resistance, heart problems and immune disturbances.  Increased oxidative  stress also occurs during exposure to physical or emotional stressors, and is associated with an increased rate of cellular aging and death. Although the exact underlying mechanisms are not fully understood, it is well-established that living in fear is not good for us.

funny-fear-duck-watching-you

WHATEVER YOUR FEAR……ITS NOT HEALTHY.

What about dogs? Although the relationship between prolonged stress, health and lifespan is an active area of research in human subjects, until recently this association had not been studied in dogs.

The Study: Nancy Dreschel, a veterinarian at Pennsylvania State University, asked the question: “Are dogs who are more anxious or fearful at increased risk for health problems and a shortened life span?”(4).  The study used a web-based questionnaire to collect information from people who owned a dog that had died within the previous five-year period. The survey included questions about the dog’s demographics, social environment, behavior, training history, health, and daily interactions with the owner. A set of questions adapted from the validated C-BARQ program  was used to collect detailed information about the presence or absence of fear-related and anxious behaviors. Age and cause of death were also recorded. The survey was available on-line for 7 months and resulted in 721 complete surveys that were used in the analysis.

The Results: As expected, body size and weight were negatively correlated with lifespan. It is well-established that large/giant dogs have a shorter average life span than small and medium size dogs. In addition, neutered dogs had a longer lifespan than intact dogs and accidental deaths were associated with a younger age of death. When body size, neuter status, and accidental death were controlled for, several significant relationships were found between behavior and lifespan:

  1. A significant negative correlation was found between the fear of unfamiliar people and lifespan. This means that dogs who experienced a lifelong fear of strangers tended to die at a younger age than dogs who did not experience this type of fear.  However, the earlier age of death in this subset of fearful dogs was not associated with any particular disease. (Because long-term activation of the HPA axis negatively affects the immune system, it was speculated that fearful dogs would be more susceptible to cancer, infections, or immune-mediated disorders. However, this relationship was not found in these data).
  2. The presence of non-social fears (fear of new places or things) and separation anxiety were both positively associated with chronic skin problems. The underlying mechanism might be the effects of long-term stress on the immune system and skin health, a relationship that has been reported in human subjects. However, this study’s design did not allow determination of causation, so conclusions regarding the underlying cause for this relationship could not be made.
  3. Lifespan was strongly and positively correlated with owner-reported “good” behavior. Dogs who were perceived as being well-behaved by their owner lived longer than those who were reported to be less well-behaved. Multiple factors may have been in play with this relationship. Because problem aggression was not specifically studied, euthanasia for aggression may have been a significant contributing factor. Less dramatically, owners who reported their dogs as less well-behaved may have been less bonded to the dog and more likely to euthanize at a younger age or to decline treatment for a serious illness. It is also possible that well-behaved dogs tend to live longer because they experience a less stressful and more harmonious home environment with their owner. Because none of these factors were studied separately, the exact cause or causes of this relationship could not be teased out, but certainly warrants additional study.
Feraful Dog Greeting

Chronic Fear of Strangers is Related to Decreased Life Span

Take Away for Dog Folks: Remember that survey studies provide information through the eyes of the owner and, in this case, the collected data were also retrospective (historical) in nature.  These factors must always be considered when making conclusions about survey studies. In addition, the statistical tests used in this study tell us if two or more factors are related (i.e. correlated), but cannot provide information about the direction of that relationship or if there is another underlying cause that was not identified.  Even considering these limitations, the results of this study suggest that prolonged fear and anxiety not only impact a dog’s quality of life, but may also contribute to an early death and increased susceptibility to chronic health (skin) problems. Helping dogs to overcome fear is vital to improving their lives and our relationships with them. For those of you who are working with these dogs on a daily basis, thank you for all that you do (5).

References and Information Sources:

  1.  Cavigelli SA, McClintock MK. Fear of novelty in infant rats predicts adult corticosteroid dynamics and an early death. Proceedings of the National Academy of Science USA 2003;100:16131-16136.
  2. McEwen BS. Stressed or stressed out? Journal of Psychiatric Neuroscience 2005; 30:315-318.
  3. Schultz R, Beach SR. Caregiving as a risk factor for mortality. Journal of the American Medical Association 1999; 282:2215-2219.
  4. Dreschel NA. The effects of fear and anxiety on health and lifespan in pet dogs. Applied Animal Behaviour Science 2010; 125:157-162.
  5. An excellent source of information for working with fearful dogs is Debbie Jacob’s book “Guide to Living With & Training a Fearful Dog and her blog, Fearful Dogs.