Category Archives: research

Treating heart disorders in dogs

A novel therapy tested by University of Guelph scientists for treating a fatal heart disorder in dogs might ultimately help in diagnosing and treating heart disease in humans.

Ontario Veterinary College (OVC) professors Glen Pyle and Lynne O’Sullivan have also identified potential causes of inherited dilated cardiomyopathy (DCM) or “weak heart.”

The groundbreaking study was published this month in the American Journal of Physiology.

Cardiology exam

“The cardiovascular systems of dogs and people are very similar,” said Pyle, a professor in OVC’s Department of Biomedical Sciences and a member of U of G’s Centre for Cardiovascular Investigations.

“It allows us to do comparative investigations that can advance understanding of this fatal condition.”

In both dogs and people with DCM, the weakened heart muscle becomes unable to pump blood around the body. The cause of the problem is often unknown, although it’s common to involve genetics.

Researchers suspect malfunctioning muscle proteins cause the heart to weaken, allowing it to dilate like an overfilled balloon.

DCM is the second leading cause of heart failure in dogs, and it’s especially common in large breeds. Dogs typically show no symptoms until the disease is well-advanced.

The condition is often inherited; up to 60 per cent of Doberman Pinschers are affected during their lifetime.  Other breeds such as Irish wolfhounds and Great Danes also have high rates.

In people, 30 to 50 per cent of DCM cases are hereditary.

The end result of DCM is congestive heart failure. While medical advances have reduced deaths from congestive heart failure by 40 per cent in the past decade, the condition still afflicts hundreds of thousands of Canadians, and the five-year mortality rate remains high.

Aging populations worldwide are likely to cause dramatic increases in the rate of heart failure in the upcoming decades, Pyle said.

“The cause of a substantial percentage of DCM cases remains unknown,” he said.  “This is why it’s urgent to develop novel agents that can improve heart function.”

For the study, Pyle and O’Sullivan, a clinical cardiologist in OVC’s Health Sciences Centre, worked with researchers at the University of Washington to test a novel therapy in diseased heart cells.

 The therapy involves introducing a molecule involved in muscle contraction. In heart cells from dogs with DCM, it restored normal function. The next step is developing a gene therapy that would allow the molecule to be produced in heart muscle cells in patients with DCM.

“This suggests it’s a promising therapeutic approach worth further investigating for the treatment of DCM,” said O’Sullivan. One of 10 board-certified veterinary cardiologists in Canada, she runs OVC’s Doberman DCM screening program.

The researchers also discovered some problems in the heart muscle that likely contribute to DCM.  “This may shed light on the mechanical impairment in failing hearts,” Pyle said.

The Guelph scientists are also working with researchers in Finland on DCM genetics and proteins. That work might lead to development of therapies for targeting specific proteins, said Pyle.

Both researchers belong to U of G’s Centre for Cardiovascular Investigations, one of a few centres worldwide studying heart disease from single molecules to clinical applications.

Source:  University of Guelph media release

It’s safe to cuddle when you’re sick

This winter, when you are home sick with the cold or flu cuddling with your dog or cat may feel like just what the doctor ordered.

A Vanderbilt infectious disease expert, while stopping short of actually prescribing in-home “pet therapy” for colds or flu, says that if having your companion by your side makes you feel better, go right ahead. Pets won’t catch or spread human viruses.

Izzy, greyhound, uin bed and ready to cuddle
“The pet is a comfort, not a hazard,” said William Schaffner, M.D., professor of Preventive Medicine at Vanderbilt University Medical Center. Even somebody who pets the dog or cat after you is unlikely to catch your virus that way, and “you can’t get a cold or the flu from your dog or cat,” Schaffner said.

While pets are pretty much off the hook, Schaffner says the true hazard in catching a virus comes from fellow two-legged creatures.

“Flu is transmitted person-to-person through close personal contact. If you get within my breathing zone, within three feet, I can transfer the influenza virus to you. I breathe it out, you breathe it in, and you can be infected,” Schaffner said.

Colds and flu can also be transmitted by hand—handshaking extroverts take note—or via some surfaces, such as when a sick person touches a doorknob, for example, and somebody else touches the same surface, and then touches his or her face.

“People should wash their hands often and use hand sanitizer,” Schaffner said. “Also, when flu is rampant in the community, greet friends with an elbow bump rather than a handshake.”

People and their pets have this in common: the best way to avoid getting sick is to be immunized—with pets it’s their vaccinations, and with people it’s a flu shot.

Source:  Newswise media release

Study shows dogs can recognise human emotions

Dogs can recognise emotions in humans by combining information from different senses – an ability that has never previously been observed outside of humans, a new study reveals.

For the first time, researchers have shown that dogs must form abstract mental representations of positive and negative emotional states, and are not simply displaying learned behaviours when responding to the expressions of people and other dogs.

The findings from a team of animal behaviour experts and psychologists the University of Lincoln, UK, and University of Sao Paulo, Brazil, are published in the Royal Society journal Biology Letters.

The researchers presented 17 domestic dogs with pairings of images and sounds conveying different combinations of positive (happy or playful) and negative (angry or aggressive) emotional expressions in humans and dogs. These distinct sources of sensory input – photos of facial expressions and audio clips of vocalisations (voices or barks) from unfamiliar subjects – were played simultaneously to the animals, without any prior training.

The team found the dogs spent significantly longer looking at the facial expressions which matched the emotional state (or valence) of the vocalisation, for both human and canine subjects.

Dogs and emotions study

The integration of different types of sensory information in this way indicates that dogs have mental representations of positive and negative emotional states of others.

Researcher Dr Kun Guo, from the University of Lincoln’s School of Psychology, said: “Previous studies have indicated that dogs can differentiate between human emotions from cues such as facial expressions, but this is not the same as emotional recognition.

“Our study shows that dogs have the ability to integrate two different sources of sensory information into a coherent perception of emotion in both humans and dogs. To do so requires a system of internal categorisation of emotional states. This cognitive ability has until now only been evidenced in primates and the capacity to do this across species only seen in humans.”

Co-author Professor Daniel Mills, from the School of Life Sciences at the University of Lincoln, said: “It has been a long-standing debate whether dogs can recognise human emotions. Many dog owners report anecdotally that their pets seem highly sensitive to the moods of human family members.

However, there is an important difference between associative behaviour, such as learning to respond appropriately to an angry voice, and recognising a range of very different cues that go together to indicate emotional arousal in another. Our findings are the first to show that dogs truly recognise emotions in humans and other dogs.

“Importantly, the dogs in our trials received no prior training or period of familiarisation with the subjects in the images or audio. This suggests that dogs’ ability to combine emotional cues may be intrinsic. As a highly social species, such a tool would have been advantageous and the detection of emotion in humans may even have been selected for over generations of domestication by us.”

Source: AlphaGalileo media release

New twist in tale of dogs’ origins

The origin of dogs has inspired a lingering controversy in academia. Where and when did dogs first split off from wolves? One of the top dogs in this dispute, population genetics expert Peter Savolainen of Sweden’s KTH Royal Institute of Technology, isn’t about to roll over. He hopes his latest research will finally settle the matter.

Some researchers say canines first split off from wolves in the Middle East; others say it happened in Europe. But Savolainen has long held that dogs originated in South East Asia alone, and he says his team has compiled new evidence that confirms his earlier findings.

The study concludes that the split with wolves occurred about 33,000 years ago.

Savolainen’s earlier studies were based on analysis of mitochondrial DNA. But recently other researchers have used data from nuclear DNA to refute those findings, arguing that dogs originated in the Middle East, Central Asia or Europe.

But apparently, those researchers were thrown off the scent, according to Savolainen. The data they relied on did not include samples from South East Asia, he says. So if, as Savolainen says, dogs did indeed come from South East Asia, these studies would not have been able to detect it.

Photo by IStock

Photo by IStock

“Which is why we analysed the entire nuclear genome of a global sample collection from 46 dogs, which includes samples from southern China and South East Asia,” he says. “We then found out that dogs from South East Asia stand out from all other dog populations, because they have the highest genetic diversity and are genetically closest to the wolf.”

Savolainen says this provides strong evidence that the dog originated in South East Asia, which confirms his earlier studies of Mitochondrial DNA.

“We also found that the global dog population is based on two important events: the dog and wolf populations first began to split off about 33,000 years ago in South East Asia. The global spread of dogs followed about 18,000 years later.

He says one explanation for the split between dogs and wolves 33,000 years ago could be that the wolf population became divided and the south Chinese wolf developed into dogs. In that case, it is possible the global spread of dogs out of South East Asia is associated with domestication.

“The dog’s story thus appears to have begun 33,000 years ago, but the exact path to the fully-domesticated dogs that spread throughout the world 15,000 years ago is not yet clear,”

Savolainen, along with 14 other scientists, recently published the scientific article “Out of Southern East Asia: The Natural History of domestic dogs across the world.

Source:  AlphaGalileo media release

Dogs give friends food (prosocial behavior in dogs)

A readiness to help and a positive attitude toward others are considered foundations of human relationships and human cooperation. But not only humans cooperate and support each other, animals do so, too. A group of ethologists from the Messerli Research Institute at the Vetmeduni Vienna have shown for the first time that dogs also behave prosocially toward others – provided that they know the other dog. The results were published in Nature’s Scientific Reports.

Compared to the rest of the animal kingdom, the human capacity for cooperation is something quite special. Cooperating with one another requires a certain amount of prosocial behaviour. This means helping others without any direct personal benefit.

“Dogs and their nearest relatives, the wolves, exhibit social and cooperative behaviour, so there are grounds to assume that these animals also behave prosocially toward conspecifics. Additionally, over thousands of years of domestication, dogs were selected for special social skills,” explains study director Range. For this reason, Range and her colleagues Mylene Quervel-Chaumette, Rachel Dale and Sarah Marshall-Pescini studied 16 dogs to test their readiness to benefit familiar versus unfamiliar partners.

The researchers studied the prosocial behaviour of the animals using a bar-pulling task in which the dogs had to pull trays and decide whether a second dog would receive a treat or not. In the test, the donor dogs used their mouths to pull a string to bring a tray toward a second dog. They could choose either an empty tray or a tray containing a treat on the partner’s side.

The donor dog (right) can pull a tray and donate food to the receiver-dog (left). (Photo: Mylène Quervel-Chaumette/Vetmeduni Vienna)

The donor dog (right) can pull a tray and donate food to the receiver-dog (left). (Photo: Mylène Quervel-Chaumette/Vetmeduni Vienna)

Dogs donate to familiar partners more often than to unfamiliar ones

Whether the donor dogs knew the recipient made a difference. Donor dogs pulled the giving tray more often for familiar dogs than for unfamiliar ones. “Dogs truly behave prosocially toward other dogs. That had never been experimentally demonstrated before. What we also found was that the degree of familiarity among the dogs further influenced this behaviour. Prosocial behaviour was exhibited less frequently toward unfamiliar dogs than toward familiar ones.

Prosocial behaviour put to the test

In the bar-pulling task, the donor dogs decided whether another dog would receive a treat or not. The donor dog itself did not get the treat. The only purpose of the task was to benefit the other dog. By conducting several control tests, the researchers excluded the possibility that the dogs were simply pulling the trays for the fun of it. Donor dogs were reserved in pulling the tray when an unfamiliar dog was in the next enclosure.

At the end of each test run, the researchers conducted another test to show that the donor dogs knew what pulling the tray meant. They allowed the donor dogs to pull on a tray to give themselves a treat, and all dogs did just that. “This control excludes the possibility that the dogs did not pull on the tray out of fear of the unfamiliar dogs. Given the same situation, the dogs gladly gave themselves a treat,” says Range.

“We were also able to disprove the argument that the dogs pulled the string less frequently because they were distracted by the unfamiliar partner during the test. Only rarely did a donor dog interact with the unfamiliar dog,” Range explains.

Source:   Vetmeduni Vienna media release

Dogs may be sloppy drinkers…but they get the job done

Researchers at the Virginia Tech College of Engineering can tell the story of dog lapping.

Using photography and laboratory simulations, researchers studied how dogs raise fluids into their mouths to drink. They discovered that sloppy-looking actions at the dog bowl are in fact high-speed, precisely timed movements that optimize a dogs’ ability to acquire fluids.

Old dog drinking

They have published their research in the Proceedings of the National Academy of Sciences.

Researchers also compared what they learned about how dogs drink with what they knew from previous studies of cats. The scientists discovered that even though feline and canine mouths structurally are similar, their approaches to drinking are as different as — cats and dogs.

“We know cats and dogs are quite different in terms of behavior and character,” said Sunghwan “Sunny” Jung, an associate professor of biomedical engineering and mechanics. “But before we did fundamental studies of how these animals drink fluids, our guess was dogs and cats drink about the same way. Instead we found out that dogs drink quite differently than cats.”

Dogs and cats are biting animals and neither have full cheeks. But without cheeks, they can’t create suction to drink — as people, horses, and elephants do. Instead they use their tongues to quickly raise water upward through a process involving inertia.

Both animals move their tongues too quickly to completely observe by the naked eye. But dogs accelerate their tongues at a much faster rate than cats, plunging them into the water and curling them downward toward their lower jaws, not their noses.

They quickly retract their tongues and a column of water forms and rises into their mouths, but they also curl the underside of their tongues to bring a tiny ladle of water upward.

Dogs precisely bite down to capture the water. In an instant they reopen their mouths and immerse their tongues back into the water.

Cats, on the other hand, lightly touch the surface of the water with their tongues, usually never fully immersing them, according to previous imaging by Jung and other researchers. When their tongues rise into their mouths, liquid adheres to the upper side, forming an elegant water column.

When dogs accelerate their tongues upwards, the latest research reveals a water column rising, but some water remains in the ladle of the tongue and is tossed to either side of the dog’s mouth or it falls downwards.

Although dogs do not use their tongues to actively scoop water into their mouths, it is possible that the scooped liquid has some positive effect on the water column dynamics below the tongue, the researchers said.

“Dog drinking is more acceleration driven using unsteady inertia to draw water upward in a column, whereas cats employ steady inertia,” Jung said.

In all, 19 dogs of various sizes and breeds were volunteered for filming by their owners. Thirteen of the dogs were filmed outdoors at their owners’ residences in the Blacksburg, Virginia, area. The remaining six were filmed at the Virginia Tech campus.

“This was a basic science study to answer a question very little was known about — what are the fundamental mechanics of how dogs drink?” said Sean Gart, a graduate student in biomedical engineering and mechanics who filmed the dogs. “Cats tend be viewed as neater, dogs are messier, but dogs really have to accelerate their tongues to exploit the fluid dynamics of the water column.”

The researchers measured tongue motion, recorded water volumes, and generally measured lapping in the dogs. They used the results to generate a physical model in the laboratory of the tongue’s interaction with the air-fluid interface, according to Jake Socha, an associate professor of biomedical engineering and mechanics at Virginia Tech.

Source:  Newswise media statement

Can your dog boost your sex appeal?

Yes, according to a new study published in Anthrozoös,  a multidisciplinary journal of the interactions of people and animals.

Dogs and dating

Photo courtesy of http://www.DogChannel.com

In collaboration with the pet store chain PetSmart, the researchers recruited 1,210 single pet owners through the online dating service Match.com. In the pool of participants, 60% were women and 40% were men; 72% were dog owners and 42% cat owners.

The subjects took a 21-question online survey about how pets entered into their dating lives and 35% percent of women and 26% of men said they had been more attracted to someone because they owned a pet.

Dogs won 500 of the 600 votes for the sexiest pet a guy could own.

Author of the recently published article entitled ‘The Roles of Pet Dogs and Cats in Human Courtship and Dating’ Peter Gray, said: “The direction of these patterns in results was toward cats being exploited less often than dogs as “social tools” in the dating world”.

So if you want to increase your dating chances, get a dog.

Source:  Taylor & Francis media release

The Roles of Pet Dogs and Cats in Human Courtship and Dating, Peter B. Gray et al, Volume 28, Issue 4, 2015, Anthrozoös: A multidisciplinary journal of the interactions of people and animals.

Read the full article online:http://www.tandfonline.com/doi/pdf/10.1080/08927936.2015.1064216