Tag Archives: Uppsala University

Dog ownership linked to lower mortality

Posted on November 18, 2017 | 3 comments

A team of Swedish scientists have used national registries of more than 3.4 million Swedes aged 40 to 80 to study the association between dog ownership and cardiovascular health. Their study shows that dog owners had a lower risk of death due to cardiovascular disease or to other causes during the 12-year follow-up.

A total of more than 3.4 million individuals without any prior cardiovascular disease in 2001 were included in the researchers’ study linking together seven different national data sources, including two dog ownership registers. The results are being published for the first time in Scientific Reports. The goal was to determine whether dog owners had a different risk of cardiovascular disease and death than non-dog owners.

An elderly couple walks their dalmatian dog. Credit: © Myroslava / Fotolia

“A very interesting finding in our study was that dog ownership was especially prominent as a protective factor in persons living alone, which is a group reported previously to be at higher risk of cardiovascular disease and death than those living in a multi-person household. Perhaps a dog may stand in as an important family member in the single households. The results showed that single dog owners had a 33% reduction in risk of death and 11% reduction in risk of myocardial infarction during follow-up compared to single non-owners. Another interesting finding was that owners to dogs from breed groups originally bred for hunting were most protected,” says Mwenya Mubanga, lead junior author of the study and PhD student at the Department of Medical Sciences and the Science for Life Laboratory, Uppsala University.

In Sweden, every person carries a unique personal identity number. Every visit to a hospital is recorded in national databases, accessible to researchers after de-identification of data. Even dog ownership registration has been mandatory in Sweden since 2001. These scientists studied whether being registered as a dog-owner was associated with later diagnosis of cardiovascular disease or death from any cause.

“These kind of epidemiological studies look for associations in large populations but do not provide answers on whether and how dogs could protect from cardiovascular disease. We know that dog owners in general have a higher level of physical activity, which could be one explanation to the observed results. Other explanations include an increased well-being and social contacts or effects of the dog on the bacterial microbiome in the owner,” says Tove Fall, senior author of the study and Associate Professor in Epidemiology at the Department of Medical Sciences and the Science for Life Laboratory, Uppsala University.

“There might also be differences between owners and non-owners already before buying a dog, which could have influenced our results, such as those people choosing to get a dog tending to be more active and of better health. Thanks to the population-based design, our results are generalisable to the Swedish population, and probably also to other European populations with similar culture regarding dog ownership,” says Tove Fall.

The study was conducted by researchers at Uppsala University, Karolinska Institutet, Stanford University and the Swedish University of Agricultural Sciences.

Source: Uppsala University media release

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Posted in Dogs, research

Tagged cardiovascular health, mortality, Scientific Reports, Uppsala University

Early contact with dogs linked to lower risk of asthma

Posted on November 4, 2015 | 1 comment

A team of Swedish scientists have used national registries encompassing more than one million Swedish children to study the association between early life contact with dogs and subsequent development of asthma.

The new study found that children who grew up with dogs had about 15 percent lower risk of asthma than children without dogs.

Tove Fall is Assistant Professor in Epidemiology at the Department of Medical Sciences and the Science for Life Laboratory.
Photograph: Mikael Wallerstedt

A total of more than one million children were included in the researchers’ study linking together nine different national data sources, including two dog ownership registers not previously used for medical research. The results are being published for the first time in JAMA Pediatrics. The goal was to determine whether children exposed to animals early in life are at different risk of asthma.

‘Earlier studies have shown that growing up on a farm reduces a child’s risk of asthma by about half. We wanted to see if this relationship also was true also for children growing up with dogs in their homes. Our results confirmed the farming effect, and we also saw that children who grew up with dogs had about 15 percent less asthma than children without dogs. Because we had access to such a large and detailed data set, we could account for confounding factors such as asthma in parents, area of residence and socioeconomic status’ says Tove Fall, Assistant Professor in Epidemiology at the Department of Medical Sciences and the Science for Life Laboratory, Uppsala University. She coordinated the study together with researchers from Karolinska Institutet in Stockholm, Sweden.

In Sweden, every person carries a unique personal identity number. Every visit to a specialist physician and every prescription made are recorded in national databases, accessible to researchers after de-identification of data. Even dog ownership registration is mandatory in Sweden since 2001. These scientists studied whether having a parent registered as a dog-owner or animal farmer was associated with later diagnosis or medication for childhood asthma.

’These kind of epidemiological studies look for associations in large populations but do not provide answers on whether and how animals could protect children from developing asthma. We know that children with established allergy to cats or dogs should avoid them, but our results also indicate that children who grow up with dogs have reduced risks of asthma later in life. Thanks to the population-based design, our results are generalizable to the Swedish population, and probably also to other European populations with similar culture regarding pet ownership and farming‘ says Catarina Almqvist Malmros, senior author of the study, Paediatrician at Astrid Lindgren Children’s Hospital and Professor in Clinical epidemiology at Dept of Medical Epidemiology and Biostatistics at Karolinska Institutet, Stockholm.

Source: Uppsala University media release

In 2012, I wrote about another study linking childhood asthma and dog ownership in Of dogs, house dust and asthma…

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Posted in research

Tagged asthma, epidemiology, Sweden, Uppsala University

Using GPS to understand sheep herding

Posted on September 13, 2014 | Leave a comment

Dr Andrew King of Swansea University has used GPS technology to understand how sheepdogs do their jobs so well.

He fitted a flock of sheep and a sheepdog with backpacks containing extremely accurate GPS devices designed by colleagues at the Royal Veterinary College, London. Daniel Strömbom of Uppsala University and colleagues then used data from these devices, together with computer simulations, to develop a mathematical shepherding model.

The team found that sheepdogs likely use just two simple rules: to collect the sheep when they’re dispersed and drive them forward when they’re aggregated. In the model, a single shepherd could herd a flock of more than 100 individuals using these two simple rules.

Andrew King explained, “If you watch sheepdogs rounding up sheep, the dog weaves back and forth behind the flock in exactly the way that we see in the model. We had to think about what the dog could see to develop our model. It basically sees white, fluffy things in front of it. If the dog sees gaps between the sheep, or the gaps are getting bigger, the dog needs to bring them together.”

Daniel Strömbom said, “At every time step in the model, the dog decides if the herd is cohesive enough or not. If not cohesive, it will make it cohesive, but if it’s already cohesive the dog will push the herd towards the target.”

King believes that the research team’s model will have many applications for tasks like crowd control, herding of livestock, and keeping animals away from sensitive areas. The algorithm developed could be used to program robots for these tasks.

Source: Natural Environment Research Council media release

Risk factors for bone cancer in dogs

Posted on December 13, 2013 | Leave a comment

Bone cancer in dogs is affected by a variety of genetic risk factors, researchers from Uppsala University and the Broad Institute have found. They’ve published their results in the journal Genome Biology.

Osteosarcoma, a type of bone cancer, is similar in humans and dogs – although in dogs it is more common. In the current study, the researchers compared the genome of sick and healthy dogs from three different breeds to find inherited risk factors for the disease.

“The key is that we find many different risk factors within each breed. We already knew that Greyhounds, Rottweilers and Irish wolfhounds are at increased risk of developing bone cancer and our results explain much of the increased risk”, said Emma Ivansson, scientist at SciLifeLab and Uppsala University.

The study demonstrated that each breed has its own risk genes, but these genes converge in common disease mechanisms.

“Our results show that the pathways involved in bone formation and growth are important for the disease. Because of the great similarities between bone cancer in dogs and humans, we believe that our findings may contribute to an increased understanding of how bone cancer develops in humans”, said Kerstin Lindblad-Toh, professor at Uppsala University and Co-Director of the SciLifeLab and Director of Vertebrate Genome Biology at the Broad Institute.

Researchers identify gene associated with eczema in dogs

Posted on May 18, 2013 | Leave a comment

A novel gene associated with canine atopic dermatitis has been identified by a team of researchers led by professors Kerstin Lindblad-Toh, Uppsala University and Åke Hedhammar, SLU, Sweden. The gene encodes a protein called plakophilin 2, which is crucial for the formation and proper functioning of the skin structure, suggesting an aberrant skin barrier as a potential risk factor for atopic dermatitis.

Details appear in the open-access journal PLoS Genetics.

Atopic dermatitis (or eczema) is an inflammatory, relapsing non-contagious skin disease affecting about 3-10 percent of dogs. The skin of a patient with atopic dermatitis becomes easily irritated by various allergens such as certain types of food, pollens or house mites. Such irritation causes very strong itching which leads to scratching, redness and flaky skin that becomes vulnerable to bacterial and yeast infections.

Despite many scientific efforts, little has been known about the genetics of the disease. In their study, researchers from Uppsala University, SLU and Broad Institute, compared DNA samples from a large group of German shepherd dogs affected by atopic dermatitis with DNA coming from healthy dogs to reveal the specific DNA segment associated with the disease.

“With the help of pet owners, we have managed to collect a unique set of DNA samples from sick and healthy dogs which allowed us to gain insight into atopic dermatitis genetics,” said first author Katarina Tengvall, Uppsala University.

Purebred dogs such as German shepherds have been selected for specific physical features for several generations. Selection led to an inadvertent enrichment for disease-risk genes in certain breeds. Moreover, the resulting architecture of canine DNA makes it easier to pinpoint segments that carry these disease risk-genes. This helped the researchers to reveal the genetics of atopic dermatitis. They found a region associated with the atopic dermatitis containing the gene PKP-2, which encodes Plakophilin-2, a protein involved in the formation and maintaining of the proper skin structure.

“The finding that certain variants of the PKP-2 gene may increase the risk of developing the disease opens new possibilities in understanding the disease mechanism leading to atopic dermatitis,” continues Katarina Tengvall.

These findings will not only lead to better understanding of the disease, which may lead to better treatment strategies long term. It also opens up the possibilities of development of a genetic test for the disease.

“Our study suggests that plakophilin-2 and an intact skin barrier is important to avoid atopic dermatitis”, says senior author, Kerstin Lindblad-Toh, professor at Uppsala University and Director of SciLifeLab Uppsala. “Another gene involved in the skin barrier has recently been linked to human atopic dermatitis emphasizing the similarity between canine and human atopic dermatitis” said Kerstin Lindblad-Toh.

Source: AlphaGalileo Foundation media statement

Hug me, I need the oxytocin

Posted on April 7, 2012 | 1 comment

Oxytocin is a mammalian hormone that is released during the act of touching and hugging. For these reasons, the hormone is often referred to as ‘the cuddle hormone’ or ‘the love hormone.’ (The hormone is also released during childbirth, by the way).

As a dog owner, your relationship with your dog is likely to involve you and your dog triggering the release of oxytocin in one another. Temple Grandin, animal behaviourist and autism researcher, has found that ‘A dog’s oxytocin levels rise when his owners pet him and petting his dog raises the owner’s oxytocin too.’ In other words, this hormone plays a role in the human-animal bond.

In 2003, J.S.J. Odendaal and R.A. Meintjes of the Life Sciences Institute at Pretoria published research into the blood levels of endorphins, oxytocin, prolactin, B-phenylethylamine and dopamine (all associated with pleasure response or relaxation) and cortisol (a known stress hormone) in people and dogs both before and after they interacted with each other. The researchers compared levels of the neurochemicals under three scenarios: 1) after people petted their own dogs 2) after they petted unfamiliar dogs and 3) after they sat quietly and read a book.

In both humans and dogs, the levels of the pleasure-response chemicals rose after 5 to 24 minutes. At the same time, cortisol levels in humans fell as they spent time with their pets. The increase in oxytocin was highest in the group where people interacted with their own dogs, as opposed to dogs that were unfamiliar to them.

In 2008, Miho Nagasawa’s research team in Japan showed that only eye contact was necessary between dogs and their humans to increase oxytocin levels. After 30 minutes of contact with their dog, owners showed an increase in oxytocin levels.

Dr Kerstin Uvnäs-Moberg from Uppsala University, studies oxytocin and its effects. Her 2010 study showed that women and their dogs experienced increases in their oxytocin levels after only 10 minutes of contact. When compared to a survey of the women, their oxytocin response was in direct correlation with the quality of the bond they felt for their pet.

For those of us who have experienced this bond during our lives, it is probably not surprising that there is a scientific reason for our feelings and that it is hormone-related. But it’s nice to have science on our side.

For those of you raising puppies, these studies show that there is a good scientific reason to ensure your puppy is socialised. It is not surprising that dogs involved in hoarding cases or puppy mills are withdrawn and in many cases frightened of humans. They aren’t accustomed to the positive effects of oxytocin release and in many cases have suffered other traumas.

Hey Daisy, give me a hug…I need the oxytocin.

Have you hugged your dog today?

Kathleen Crisley, specialist in dog massage, rehabilitation and nutrition/food therapy, The Balanced Dog, Christchurch, New Zealand

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Posted in dog ownership, Dogs, research

Tagged autism, cortisol, cuddle hormone, dog ownership, hug, In Defence of Dogs, J.S.J. Odendaal and R.A. Meintjes, John Bradshaw, Kerstin Uvnäs Moberg, love hormone, Miho Nagasawa, oxytocin, Temple Grandin, Uppsala University