Category Archives: research

Adjusting stress levels for mellow vs hyper dogs

People aren’t the only ones who perform better on tests or athletic events when they are just a little bit nervous — dogs do too. But in dogs as in people, the right amount of stress depends on disposition.

A new study by researchers at Duke University finds that a little extra stress and stimulation makes hyper dogs crack under pressure but gives mellow dogs an edge.  (These findings will be relevant to any owner who is competing in agility or obedience with their dog.)

The findings appear online in the journal Animal Cognition.

According to an idea in psychology called the Yerkes-Dodson law, a little stress can be a good thing, but only up to a point.

A task that isn’t demanding or challenging enough can make it hard to stay engaged and perform at one’s peak. But when the pressure becomes too much to handle, performance is likely to suffer again.

The idea is the relationship between stress and performance follows a Goldilocks model:  Both people and animals function best when the level of stress is not too much, nor too little, but just right.

When you’re taking a test, for example, it helps to be a little bit anxious so you don’t just blow it off,” said study co-author Emily Bray, who was an undergraduate at Duke at the time of the study. “But if you’re too nervous, even if you study and you really know the material, you aren’t going to perform at your best.”

Researchers first observed this pattern more than a hundred years ago in lab rats, but it has since been demonstrated in chickens, cats and humans. In a new study, a Duke team consisting of Bray and evolutionary anthropologists Evan MacLean and Brian Hare of Duke’s Canine Cognition Center wanted to find out if the conditions that enable certain animals to do their best also depend on the animal’s underlying temperament.

In a series of experiments, the researchers challenged dogs to retrieve a meat jerky treat from a person standing behind a clear plastic barrier that was six feet wide and three feet tall. To get it right, the dogs had to resist the impulse to try to take the shortest path to reach the treat — which would only cause them to whack into the barrier and bump their heads against the plastic — and instead walk around the barrier to one of the open sides.

In one set of trials, an experimenter stood behind the barrier holding a treat and called the dog’s name in a calm, flat voice. In another set of trials, the experimenter enthusiastically waved the treat in the air and used an urgent, excited voice. (See YouTube video at https://youtu.be/j6bfo5IlCEY – the video has been protected and so I’m unable to link it directly to this blog post).

The researchers tested 30 pet dogs, ranging in age from an eight-month-old Jack Russell terrier named Enzo to an 11-year-old Vizsla named Sienna. They also tested 76 assistance dogs at Canine Companions for Independence in Santa Rosa, California, a non-profit organization that breeds and trains assistance dogs for people with disabilities.

The researchers studied video recordings of each dog and estimated their baseline temperament in terms of tail wags per minute. “The service dogs were generally more cool in the face of stress or distraction, whereas the pet dogs tended to be more excitable and high-strung,” Bray said.

Both groups of dogs were able to solve the puzzle. But the optimal amount of stress and stimulation depended on each dog’s disposition.

For the dogs that were naturally calm and laid-back — measured by how quickly they tended to wag their tails — increasing the level of excitement and urgency boosted their ability to stay on task and get the treat.

But for excitable dogs the pattern was reversed. Increasing the level of stimulation only made them take longer.

In one high-arousal trial, a two-year-old spaniel named Charlie Brown lost it and shut down, barking and zipping around crazily until she almost ran out of time.

“In the first five trials she did fine and solved the puzzle quickly with no problems,” Bray said. “Then when the high-arousal trials started she choked. She just couldn’t figure it out.”

“Adding more excitement pushed the pet dogs over the edge and impaired their ability to perform at their peak,” Bray said.

The results will help researchers develop better tests to determine which dogs are likely to graduate from service dog training programs, for example.

Source:  Duke University media release

Drug trials in pet dogs with cancer

Physiological similarities between dogs and humans, and conserved genetics between some dog and human cancers, can allow pet dogs to serve as useful models for studying new cancer drugs, says Dr Timothy Fan of the University of Illinois.

Timothy Fan, professor of veterinary clinical medicine. With his personal dog, Ember

Timothy Fan, professor of veterinary clinical medicine. With his personal dog, Ember  photo by L. Brian Stauffer

In a meeting sponsored by the National Cancer Policy Forum of the National Academies’ Institute of Medicine in Washington, D.C., Fan and 15 other experts in the field described the benefits of using pet dogs with naturally occurring (rather than laboratory-induced) tumors in early cancer drug trials.

“We have a lot of dogs in the United States, approximately 70 million of them, and it’s believed that about 25 percent of pet dogs will develop some form of cancer in their lifetime,” he said. “We’re using dogs to help guide drug development for people, but at the same time we’re offering new, innovative therapies that would otherwise never be available to dogs, to help them as well.”

Several attributes make pet dogs attractive subjects for such studies, Fan said.

“Dogs tend to develop cancer as a geriatric population, just like people,” he said. “Because the tumors develop spontaneously, there is heterogeneity in that tumor population, as a human being would have. The size of the tumors and the speed of growth of those tumors are comparable in dogs and human beings. So there are many attributes of a dog that develops cancer spontaneously that recapitulate the biology that we see in people.”

Some studies have already begun using dogs to test new cancer therapies. Starting in 2007, for example, Fan began testing an anti-cancer drug called PAC-1  in pet dogs with naturally occurring lymphomas and osteosarcomas. The results in dogs allowed the scientists to advance PAC-1 as a potential therapy against human cancers. The drug is now in phase I human clinic trials.

“Another example in which dogs have been important in demonstrating drug activity was an anti-cancer compound produced by the pharmaceutical company Gilead Sciences,” he said. “The company produced a pro-drug, which must be activated by a naturally occurring enzyme in human leukocytes before it can become effective. Mice and rats lack this enzyme, but dogs have it, so the compound was tested in dogs.”

There also are limitations to the use of pet dogs in cancer drug trials.

“There are some tumors that will not be that relevant,” Fan said. “Colon cancer, for example, is heavily driven by diet, and we don’t see much colon cancer in dogs. So pet dogs might not be a suitable model for colon cancer in humans.”

“There is heterogeneity in the human population and in dogs. So I would argue that if your drug agent produces positive results in dogs, that would give me greater confidence that those findings would be translatable to people.”

Source:  University of Illinois media release

One in four dogs at Crufts is overweight

One in four dogs competing in the world’s largest canine show (Crufts) is overweight, despite the perception that entrants are supposed to represent ideal specimens of their breed, reveals research published online in Veterinary Record.

The widespread dissemination of show dog images online may be ‘normalising’ obesity in dogs, now recognised to be a common canine disorder, say the researchers.

As in people, obesity in dogs has been linked to orthopaedic problems, diabetes, respiratory disease, and certain types of cancer. It also affects both the quality and length of a dog’s life.

The researchers base their findings on 1120 online images of dogs from 28 breeds—half of which are prone to obesity–that had appeared at Crufts. This is the UK’s national dog show, and the largest of its kind in the world.

Only adult dogs that had been placed between first and fifth in their class between 2001 and 2013 were included in the study.

The images were coded and anonymised, and 960 were suitable for assessment. A second person then graded the body condition of each dog in one sitting, using a previously validated method.

Three out of four (708; 74%) of the show dogs were in ideal condition, and none was overweight. But one in four (252; 26%) was overweight.

Pugs, basset hounds, and Labrador retrievers were the breeds most likely to be assessed as being overweight. Dogs were overweight in 80% of the pug images, and in around two thirds of the basset hound (68%) and Labrador (63%) images.

The researchers say Labradors were one breed that was more likely to be assessed as overweight.   (Photo by pedigreelabrador.co.uk)

The researchers say Labradors were one breed that was more likely to be assessed as overweight. (Photo by http://www.pedigreelabrador.co.uk)

The three breeds with the highest prevalence of overweight among the online images are prone to excess weight. But, given that pugs were originally bred to be a companion dog, while hounds and Labradors were bred, respectively, for hunting and fieldwork, being overweight would not be advantageous, say the researchers.

Standard poodles, border terriers, Rhodesian ridgebacks, Hungarian vizlas and Dobermanns were the least likely breeds to be overweight.

The researchers point out that the prevalence of overweight among the show dogs was less than that reported generally for pet dogs in the UK. But the fact that “a quarter were above ideal weight is still a cause for concern,” they write.

“These dogs showcase the ideal characteristics of the pedigree breed, and there is a danger that widespread media exposure might adversely influence owner perception of optimal body shape,” they say.

The Kennel Club has recently introduced changes in policy for judging criteria, to emphasise characteristics that promote good health in dogs, say the researchers.

But breed standards of optimal condition should be reinforced for competition, to ensure consistency, they say, concluding: “Further effort is now required to educate owners, breeders and show judges so that they can all better recognise overweight condition, thus helping to prevent the development of obesity.”

Source:  EurekAlert! media release

What are you looking at? (Dogs follow the human gaze)

Dogs are known to be excellent readers of human body language in multiple situations. Surprisingly, however, scientists have so far found that dogs do not follow human gaze into distant space. Scientists at the Messerli Research Institute at the Vetmeduni Vienna investigated how this skill of dogs is influenced by aging, habituation and formal training. The outcome: Gaze following to human gaze cues did not differ over the dogs’ lifespan, however, formal training was found to directly influence gaze following in dogs.


Gaze following to distant space has been documented in many species and is considered a basic response found in many taxa. Dogs may present a special case as the researchers found evidence that they are able to follow human gaze to objects such as food or toys, but not for the comparatively simpler task of following gaze into distant space.

Two possible reasons were offered to explain this phenomenon: One reason could be habituation. Dogs lose their innate gaze following response as they age, as they are frequently exposed to human gaze cues over their lifespan and slowly stop responding to them. Another reason could be formal training such as obedience, agility, and trick training may interfere with the dogs’ response to gaze cues, since dogs are usually trained to look at the owner, to wait for commands and ignore distractions.

What influences dogs’ gaze following response to human gaze cues?

Lead author Lisa Wallis and her colleagues at the Vetmeduni Vienna investigated 145 Border Collies aged 6 months to 14 years in the Clever Dog Lab in order to address the question of whether habituation, and/or training influences dogs’ gaze following response, and to determine, for the first time, how this ability changes over the course of a dog’s life by comparing groups of dogs of different ages. 

Dogs of all ages are able to follow human gaze

The scientists tested two groups of dogs with differing amounts of formal training over their lifespan. Both groups participated firstly in a test and control condition, where their initial gaze following performance was measured. The experimenter obtained the dogs’ attention using its name and the command “watch” after which the experimenter turned her head swiftly to look at the door of the testing room in the test condition, or looked down to the floor next to her feet in the control condition. If the dogs responded by looking at the door within two seconds in the test condition but did not look at the door in the control condition, a gaze following response was recorded.

Dogs’ tendency to follow human gaze is influenced by training for eye contact
Lisa Wallis with a Border Collie in the test room. (Photo: Clever Dog Lab / Vetmeduni Vienna)

Lisa Wallis with a Border Collie in the test room. (Photo: Clever Dog Lab / Vetmeduni Vienna)

The dog follows Wallis' gaze to the door. (Photo: Clever Dog Lab / Vetmeduni Vienna)

The dog follows Wallis’ gaze to the door. (Photo: Clever Dog Lab / Vetmeduni Vienna)

 

 

 

 

 

 

 

 

 

Dogs which had a higher amount of formal training over their lifespan showed a lower gaze following response compared to dogs with little or no training. Similarly, short-term training also decreased dogs’ gaze following response and increased gaze to the human face.

The authors conclude that formal training had a stronger influence than aging or habituation on dogs’ gaze following response. This may explain why previous studies have failed to find a gaze following response when cues to distant space are used, and why in comparison to other species dogs perform relatively poorly in this task. The fact that the experimenter used strong attention-getting cues and provided contextual relevance by looking at a door may have also contributed to the positive results found in this study.

“From a very young age dogs have experience with doors when they live in human homes. The dogs develop an understanding that at any time an individual may enter the room, and therefore doors hold special social relevance to dogs”. – says Lisa Wallis.

In her current project, together with her colleague Durga Chapagain, Wallis is investigating the effects of diet on cognitive aging in older dogs. The scientists are still looking for dog owners who would like to participate in that long-term study (food is provided for free).

This research has been published in the journal Animal Behaviour.

Source:  Vedmeduni Vienna media release

The prescription for a soldier’s PTSD

I just found this very short item on the San Francisco Chronicle website.  A photo of a heavily tattooed man, his baby and his dog….

 Photo: Patty Snijders

Photo: Patty Snijders

The man is Ari Sonnenberg with his daughter, Nila Louise Sonnenberg, born April 1, 2015, and his Belgian Malinois dog, Sigmund Freud (also known as  Siggy).

Patty Snijders (Ari’s wife) says: “The dog has helped both Ari and me tremendously. He’s made our marriage stronger and prepared us for parenthood in many ways.”

A simple photograph and a lovely sentiment.  Siggy sounds very special and his presence has clearly been a help to the couple.

The body of knowledge about the value of dogs for our physical and mental health continues to grow, with research and study and stories like those of Siggy and his owners.

Kathleen Crisley, specialist in dog massage, rehabilitation and nutrition/food therapy, Canine Catering Ltd, Christchurch, New Zealand

Dogs absorb lawn chemicals

Dogs exposed to garden and lawn chemicals may have a higher risk of bladder cancer. iStockPhoto

Dogs exposed to garden and lawn chemicals may have a higher risk of bladder cancer.
iStockPhoto

 

Dogs are ingesting, inhaling and otherwise being exposed to garden and lawn chemicals that have been associated with bladder cancer, according to a new study.

The paper, which will appear in the July issue of Science of the Total Environment, also found that wind could carry the chemicals to untreated properties. The researchers also found that dogs, once contaminated by the chemicals, can transfer them to their owners.

The chemicals are common herbicides containing the following: 2,4-dichlorophenoxyacetic acid (2,4-D), 4-chloro-2- methylphenoxypropionic acid (MCPP) and/or dicamba.

“The routes of exposure that have been documented in experimental settings include ingestion, inhalation and transdermal exposures,” lead author Deborah Knapp of Purdue University’s Department of Veterinary Clinical Sciences, told Discovery News.

“In the case of dogs,” she added, “they could directly ingest the chemicals from the plant, or they could lick their paws or fur and ingest chemicals that have been picked up on their feet, legs or body.”

Scottish terriers, West Highland white terriers, Shetland sheepdogs, beagles and wire hair fox terriers are all at particular risk, the researchers suggest, because these breeds have a high genetic propensity for bladder cancer.

Knapp and her colleagues first conducted an experimental grass plot study that involved spraying various defined patches with the chemicals under different conditions. These included spraying the herbicides on plots that were green, dry brown, wet or recently mowed. The researchers next measured how much of the chemicals remained on the grass up to 72 hours post treatment.

Co-author Angus Murphy, also from Purdue, explained that dead or dying plant material does not readily absorb the chemicals, “so the herbicide can remain longer on the surface of the plant.”

He continued, “If an excessive amount of herbicide is applied, then the capacity of the target plant to take up the compound may be overwhelmed.”

In a second experiment, the researchers analyzed urine samples of dogs from households that either used herbicides or didn’t. The majority of dogs from homes that used the chemicals were found to have these same herbicides in their urine. Some dogs from untreated homes also had the chemicals in their urine.

Knapp explained that wind could cause the herbicides to travel up to 50 feet away from the application site. Neighbors who use the chemicals might therefore impact other individuals in the area.

“There are industry guidelines for restricting lawn chemical application based on wind speed, although homeowners may not be aware of these,” Knapp said.

Once contaminated, dogs can pass the chemicals on to their owners and to others. The study only looked at dogs, but the researchers suspect that cats and other pets could also be affected.

“Dogs can pick up the chemicals on their paws and their fur,” Knapp said. “They can then track the chemicals inside the house, leaving chemicals on the floor or furniture. In addition, if the dog has chemicals on its fur, the pet owner could come in contact with the chemicals when they pet or hold the dog.”

John Reif, a professor emeritus of epidemiology at the Colorado School of Public Health, told Discovery News, “The paper presents important information since exposure to 2,-4-D, a widely used broad leaf herbicide, has been associated with increased risk of cancer in pet dogs and humans.”

Reif added, “This study has potentially important implications for human health since it demonstrates widespread exposure to pet dogs. The likelihood that children, who share the local environment with their pets, are similarly exposed to these chemicals is high and thus additional studies should be conducted to evaluate this possibility.”

The researchers suggest that if owners still must use herbicides, they should follow manufacturer guidelines, allow gardens and lawns to dry before allowing pets out, wash their dog’s feet each time the dog comes inside, and consider treating the back yard one week before the front (or vice versa) so that pets will have an area of less potential chemical exposure available to them.

Source:  Discovery.com

 

Barking characterizes dogs like voices characterize people

An international group of researchers has conducted a study on canine behavior showing that gender, age, context and individual recognition can be identified with a high percentage of success through statistical and computational methods of pattern recognition applied to their barking.

The results of the study have been published in the journal Animal Cognition.

This research aimed to understand the acoustic signals obtained from dog barking when the dog subjects are subjected to certain situations. The research was conducted through the development of a computational system based on statistic modeling that is able to recognize diverse characteristics of the dog (gender, age, individual, situation).

This diagram has been used to help ‘map’ the computing system behind the research:

Photo credit:   Universidad Politécnica de Madrid (UPM)

Photo credit:
Universidad Politécnica de Madrid (UPM)

The experiments were carried out in Budapest with eight Mudi breed dogs from Hungary, usually used as sheep-dogs—three males and five females. Each dog (aged between one and 10) registered 100 barks. A total of 800 barks was obtained by placing the dogs in seven different situations: (a) alone, after the owner tied the dog to a tree; (b) playing with a ball; (c) fighting, when a human pretended to attack the dog’s owner; (d) receiving their food ration; (f) in the company of a person who was foreign to the dog; and (g) preparing to go out with the owner. Each one of the 800 barks was characterized from 29 acoustic measurements.

By using the diverse computational models obtained from the collected data during the experiment, researchers successfully recognized the dog’s gender 85.13% of the time, while the age of the dog (recoded as young, adult and old) was classified without mistakes 80.25% of the time. The task of identifying the situation in which the dog was engaged was successful 55.50% of the time, while the recognition (among the eight dogs participating in the study) of the Mudi breed was successful the 67.63% of the time.

Whilst a highly technical bit of research, particularly for those of us who are challenged by computer programming and mathematics, there are applied uses for this research such as in assessing dog behavior.  Software programs using these models could help to identify fear, anxiety and levels of aggressiveness in a dog.

Source:  Phys.org