Modern dog breeds genetically disconnected from ancient ancestors

ScienceDaily (May 21, 2012) — Cross-breeding of dogs over thousands of years has made it extremely difficult to trace the ancient genetic roots of today's pets, according to a new study led by Durham University.

An international team of scientists analyzed data of the genetic make-up of modern-day dogs, alongside an assessment of the global archaeological record of dog remains, and found that modern breeds genetically have little in common with their ancient ancestors.

Dogs were the first domesticated animals and the researchers say their findings will ultimately lead to greater understanding of dogs' origins and the development of early human civilization.

Although many modern breeds look like those depicted in ancient texts or in Egyptian pyramids, cross-breeding across thousands of years has meant that it is not accurate to label any modern breeds as "ancient," the researchers said.

Breeds such as the Akita, Afghan Hound and Chinese Shar-Pei, which have been classed as "ancient," are no closer to the first domestic dogs than other breeds due to the effects of lots of cross-breeding, the study found.

Other effects on the genetic diversity of domestic dogs include patterns of human movement and the impact on dog population sizes caused by major events, such as the two World Wars, the researchers added.

The findings were published May 21 in the scientific journal Proceedings of the National Academy of Sciences USA (PNAS). The Durham-led research team was made up of scientists from a number of universities including Uppsala University, Sweden, and the Broad Institute, in the USA.

In total the researchers analysed genetic data from 1,375 dogs representing 35 breeds. They also looked at data showing genetic samples of wolves, with recent genetic studies suggesting that dogs are exclusively descended from the grey wolf.

Lead author Dr Greger Larson, an evolutionary biologist in Durham University's Department of Archaeology, said the study demonstrated that there is still a lot we do not know about the early history of dog domestication including where, when, and how many times it took place.

Dr Larson added: "We really love our dogs and they have accompanied us across every continent.

"Ironically, the ubiquity of dogs combined with their deep history has obscured their origins and made it difficult for us to know how dogs became man's best friend.

"All dogs have undergone significant amounts of cross-breeding to the point that we have not yet been able to trace all the way back to their very first ancestors."

Several breeds, including Basenjis, Salukis and Dingoes, possess a differing genetic signature, which previous studies have claimed to be evidence for their ancient heritage, the research found.

However the study said that the unique genetic signatures in these dogs was not present because of a direct heritage with ancient dogs. Instead these animals appeared genetically different because they were geographically isolated and were not part of the 19th Century Victorian-initiated Kennel Clubs that blended lineages to create most of the breeds we keep as pets today.

The study also suggested that within the 15,000 year history of dog domestication, keeping dogs as pets only began 2,000 years ago and that until very recently, the vast majority of dogs were used to do specific jobs.

Dr Larson said: "Both the appearance and behavior of modern breeds would be deeply strange to our ancestors who lived just a few hundred years ago.

"And so far, anyway, studying modern breeds hasn't yet allowed us to understand how, where and when dogs and humans first started this wonderful relationship."

The researchers added that DNA sequencing technology is faster and cheaper than ever and could soon lead to further insights into the domestication and subsequent evolution of dogs.

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The above story is reprinted from materials provided by Durham University.

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Journal Reference:

G. Larson, E. K. Karlsson, A. Perri, M. T. Webster, S. Y. W. Ho, J. Peters, P. W. Stahl, P. J. Piper, F. Lingaas, M. Fredholm, K. E. Comstock, J. F. Modiano, C. Schelling, A. I. Agoulnik, P. A. Leegwater, K. Dobney, J.-D. Vigne, C. Vila, L. Andersson, K. Lindblad-Toh. Rethinking dog domestication by integrating genetics, archeology, and biogeography. Proceedings of the National Academy of Sciences, 2012; DOI: 10.1073/pnas.1203005109

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No fear of the 'big bad wolf:' Feeding habits of German wolves investigated

ScienceDaily (Mar. 19, 2012) — Scientists of the Senckenberg Research Institute in Görlitz have been investigating the feeding habits of wolves in the first eight years since their appearance in Germany. The results are reassuring: The proportion of livestock on the menu lies at less than one percent. The related study was published recently in the journal Mammalian Biology.

For a long time, wolves had been wiped out in Germany, now they are slowly getting back home. But not everyone is happy at the return of the wild animal. The feeding habits of Canis lupus are the subject of many legends and fables. Wolves that tear sheep apart, eat household pets and even attack people -- the return of the predators to German regions awakens fear and generates conflict amongst its inhabitants, hunters and farmers.

"The dietary habits of wolves has been the greatest point of contention with their return to Germany and it induced us to examine in closer detail the feeding habits of the wolves that migrated to Lusatia over ten years ago," explains Hermann Ansorge, head of the Zoology Department at the Senckenberg Museum of Natural History in Görlitz. "We took a look at what was on the menu for the wolves and how this has changed since the appearance of wolves in East Germany."

For this purpose the scientists collected over 3000 samples of wolf scat and tested them for undigested evidence of the animals' prey, such as hair, bones, hooves or teeth.

Using this information, supplemented by the findings of the remains of prey, it was possible for the Görlitz zoologists to determine the nutritional intake of the carnivores in detail. Wild ungulates accounted for over 96% of the wolves' prey, according to the investigation. The majority of these were roe deer (55.3%), followed by red deer (20.8%) and wild boar (17.7%). A small proportion of the prey was accounted for by the hare, at almost 3 percent.

"Less than one percent of the prey analysed was of livestock origins" adds Ansorge, continuing: "As long as sheep and other livestock are well protected and there is a sufficient supply of wild animals, the wolves will not risk confrontation with electric fences and guardian dogs."

The Görlitz zoologists investigated not only what the wolves are eating nowadays, but also how their feeding habits have changed over the years. Wolves are highly adaptable in terms of their dietary intake. For example, it is known from Canada that the wolf packs there feast on salmon in the autumn time.

"We were interested to find out how, why and how quickly the dietary composition of the wolf has changed in Saxony" explains Ansorge. The wolves in Lusatia came to Germany from Poland. There, the packs lived primarily on red deer, in contrast to the German wolves. During the early years of the study, the proportion of red deer eaten was considerably higher, whilst the ratio of roe deer was accordingly lower than in the subsequent five years. "We asked ourselves why the wolves changed their behaviour or whether the initial conditions had changed," the Görlitz zoologist continues.

In comparison to the Polish forests, those in Lusatia tend to be smaller and crossed by paths and fields. They offer the perfect expansive living space for roe deer and wild boar, whilst red deer tend to retreat to the more spacious wooded areas. Roe deer are therefore a simple and frequent prey from the wolves' perspective.

The shift in eating patterns therefore resulted from the change in the environmental conditions. The wolves quickly adapted -- they required less than two generations to become used to the new conditions of the landscape in East Germany.

Since the legal protection of wolves was introduced in 1990, it has taken more than ten years for the wolves in Germany to make themselves at home and bear pups on the Muskau Heath (a military training area). At the present time, nine wolf packs live in Lusatia with around 34 young. "The potential for conflict between man and wolf is very low" Ansorge sums up the results of the study. "There really is nothing standing in the way of the wolf returning."

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Carina Wagner, Maika Holzapfel, Gesa Kluth, Ilka Reinhardt, Hermann Ansorge. Wolf (Canis lupus) feeding habits during the first eight years of its occurrence in Germany. Mammalian Biology - Zeitschrift für Säugetierkunde, 2012; DOI: 10.1016/j.mambio.2011.12.004

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Herding sheep really are selfish

ScienceDaily (July 23, 2012) — Many animals spend time together in large groups not because they enjoy each other's company, but rather because it lowers their own chances of being eaten should an uninvited guest arrive on the scene -- or so the theory goes. Now, researchers who have strapped GPS-enabled backpacks to flocking sheep and a herding dog provide some of the first hard evidence that this "selfish herd theory" is true.

The findings appear in the July 24th issue of Current Biology, a Cell Press publication.

"We were able to track the movements of the sheep and the dog that pursued them on a second-by-second basis simultaneously," said Andrew King of The Royal Veterinary College, University of London. "In each case, we found that the sheep exhibit a strong attraction towards the center of the flock as the dog approaches," an effort to avoid the more dangerous fringe.

The selfish herd has long been a favorite explanation for grouping behavior, the researchers say. But tracking the concerted movements of many individual animals at once and predicting a predator's attack is not easy to do. As a result, there had been little semblance of proof.

The data now suggest that individual sheep under threat move continuously toward the center of the flock while the flock as a whole moves away from the threat. "It's kind of continuously folding in on itself," King says. The researchers were able to recreate that folding pattern using simple math.

Some members of the flock do seem to come out better than others, King added. Whether that's a matter of luck or ability the researchers can't yet say, though they are giving the sheep physical fitness and personality tests to look for predictable patterns. They also want to sort out the "rules" the sheep follow in order to move in such a remarkable and orchestrated way.

It turns out the new findings might even shed light on neurodegenerative diseases such as Huntington's, King says, noting that sheep are a popular model for the study of that devastating human condition. "We wanted to establish a baseline of 'normal' sheep social behavior, from which others can pinpoint the onset and progression of abnormal behaviors that may be associated with locomotor or cognitive deficits," King says.

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The above story is reprinted from materials provided by Cell Press, via EurekAlert!, a service of AAAS.

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Andrew J. King, Alan M. Wilson, Simon D. Wilshin, John Lowe, Hamed Haddadi, Stephen Hailes, A. Jennifer Morton. Selfish-herd behaviour of sheep under threat. Current Biology, 2012; 22 (14): R561 DOI: 10.1016/j.cub.2012.05.008

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Quality of life of obese dogs improves when they lose weight

ScienceDaily (Feb. 20, 2012) — Researchers at the University of Liverpool have found that overweight dogs that lose weight have an improved quality of life compared to those that don't.

It is estimated that approximately a third of the UK dog population is obese. Obesity is a serious disease and can lead to many other health disorders including diabetes, heart disease and arthritis.

A study of 50 overweight dogs, comprising a mix of breeds and genders was undertaken by scientists at the University in collaboration with the University of Glasgow, Royal Canin and the WALTHAM Centre for Pet Nutrition.

Owners completed a questionnaire to determine the health-related quality of life of their dog prior to weight loss. A follow-up questionnaire was completed by the owners of 30 dogs that successfully completed the weight loss programme, enabling changes in quality of life to be assessed. A range of life quality factors were scored, including vitality, emotional disturbance and pain. The quality of life of dogs which succeeded with their weight loss programme was also compared with those dogs that failed to lose weight successfully.

The results showed that the quality of life improved in the dogs that had successfully lost weight, in particular vitality scores increased and the score for emotional disturbance and pain decreased. Moreover, the more body fat that the dog lost, the greater the improvement in vitality.

The research also found that dogs that failed to complete their weight loss programme had worse quality of life at the outset than those successfully losing weight, most notably worse vitality and greater emotional disturbance.

Dr Alex German, Director of the Royal Canin Weight Management Clinic at the University, said: "Obesity is a risk for many dogs, affecting not only their health but also their quality of life. This research indicates that weight loss can play an important role in keeping your dog both healthy and happy."

Dr Penelope Morris, from the WALTHAM Centre for Pet Nutrition, added: "Strategies for combating obesity and keeping dogs fit and healthy include portion control, increased exercise and diets specifically formulated for overweight pets."

Established in 2004, the Royal Canin Weight Management Clinic at the University's Small Animal Hospital UK's is the world's first animal weight management referral clinic and was set up to help tackle and prevent weight problems in animals such as dogs and cats.

Veterinary surgeons from any general practice in the UK can refer overweight animals to the clinic. The patients receive a thorough medical examination, and are then given a specific dietary plan and exercise regime to follow over several weeks.

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A.J. German, S.L. Holden, M.L. Wiseman-Orr, J. Reid, A.M. Nolan, V. Biourge, P.J. Morris, E.M. Scott. Quality of life is reduced in obese dogs but improves after successful weight loss. The Veterinary Journal, 2011; DOI: 10.1016/j.tvjl.2011.09.015

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The Iberian wolf lives close to humans more for refuge than for prey

ScienceDaily (July 11, 2012) — The Iberian wolf lives in increasingly humanised landscapes, with limited food resources and its presence is not always welcome. But, according to Spanish researchers, food availability plays a secondary role compared to landscape characteristics, which can offer refuge and allow wolves to remain in human-dominated environments in Galicia.

The habitat of the Iberian wolf (Canis lupus signatus) varies greatly across the Iberian Peninsula and its diet revolves around what is available, ranging from wild animals to domestic waste. In contrast, this predator is able to survive in humanised landscapes where characteristics provide them refuge from humans.

"Although the wolf boasts highly adaptable strategies for survival, landscape is the factor we have analysed that best explains their distribution across Galicia," as explained by Luis Llaneza, researcher at Asesores en Recursos Naturales (A.RE.NA.) and lead author of the study published in the 'Diversity and Distributions' journal.

His research has allowed for the analysis of the relative influence of landscape attributes, human presence and food resources and the existence of wolves over an area of 30.000 km2 in the north-west of the Peninsula.

The scientists concentrated on indirect signs of the animal to identify their distribution in Galicia. In total, 1,594 excrement samples were analysed, which were then verified using DNA molecular analysis to locate them in the territory.

The results revealed that landscape properties are decisive in terms of animal safety at a level of 48%, whereas the presence of humans (buildings and roads) is influential at a level of 35% and food availability as 17%. Llaneza says that "as long as tolerated by humans, the wolf can be found in any place where there is refuge and food."

According to the scientists' model, the presence of wolves would increase if there were more semi-wild horses and wild ungulates. As the authors outline, "the amount of semi-wild horses in Galicia could be a key factor determining the presence of wolves in areas where wild prey or other food sources area not so abundant."

A safe refuge for the wolf

After studying the effect of altitude, land orography and refuge availability, researchers demonstrated that these mammals require their habitat to be a plant mosaic containing vegetation of more than 50 centimetres in height (bushes and shrubs) to hide in.

"These animals remain in Spain and little by little we are beginning to understand how they survive in human-dominated areas," says Llaneza. The study reveals that wolves choose high places that are difficult to access, such as areas where vegetation provides refuge from humans.

"The density of vegetation allows wolves to go unnoticed by humans," adds the researcher, who recalls that humans are the known cause of wolf death in 91% of instances. Some 65% of wolves are killed on the road, 20% by poaching and 6% by legal hunting.

With the participation of the University of Santiago de Compostela and the Doñana Biological Station (EBD-CSIC), the research team concludes that a set of variables and data analysed explains only 20% of wolf distribution in Galicia. Their next undertaking will be the study of other factors that influence wolf survival in humanised areas, such as the extent to which they are tolerated.

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Luis Llaneza, José V. López-Bao, Víctor Sazatornil. Insights into wolf presence in human-dominated landscapes: the relative role of food availability, humans and landscape attributes. Diversity and Distributions, 2012; 18 (5): 459 DOI: 10.1111/j.1472-4642.2011.00869.x

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Oral drops for dog allergies pass another hurdle

ScienceDaily (July 24, 2012) — A study reported July 24 at the World Congress of Veterinary Dermatology in Vancouver, British Columbia, shows that placing allergy drops under a dog's tongue can be as effective as allergy injections for controlling skin allergies.

In dogs, allergies to house dust, pollen, and mold cause atopic dermatitis, an itchy skin inflammation. Dogs, like people, can be desensitized through "immunotherapy" using shots or drops that deliver small doses of the allergen to "train" the immune system to tolerate foreign proteins.

Both technologies are now about a century old, but for humans and animals, allergy shots are more commonly used.

Chief author of the new study, Douglas DeBoer, a professor of dermatology at the University of Wisconsin-Madison School of Veterinary Medicine, sees several benefits emerging from the new study, which treated skin allergies in 217 dogs using allergy drops.

About 60 percent of the dogs improved significantly, DeBoer says. The drops were placed under the tongue twice a day, while allergy shots are injected every 14 days or so. Both drops and shots must be performed under a veterinarian's supervision, and their cost is comparable.

Because the drops apparently act through a different mechanism than allergy shots, they even helped dogs who had "failed" allergy shots, DeBoer says.

Dogs, like people, can rarely suffer a life-threatening anaphylactic reaction to allergy shots, resulting in collapse and shock. However, even those dogs treated in the study that had previously had such a dangerous reaction to an allergy shot did not have it with the under-the-tongue method. "Drops appear to be safer than shots in this respect," says DeBoer.

DeBoer was not always so enthusiastic about allergy drops for dogs, says Mary Morris, M.D., of Allergy Associates of La Crosse. In about 1967, her father, Dr. David Morris, started using allergy drops with increasing effect on his allergy patients. Some were farmers with severe mold allergies who suffered aching arms and swelling from allergy shots or could not find the time to visit the clinic for regular shots.

In 2006, Morris says, a clinic employee asked her to try allergy drops on a "poor little golden retriever that was losing most of its coat, scratching uncontrollably. Based on the human protocol we use at the clinic, I made my best guess at the formula for treating a dog, and it worked really well."

Intrigued with the idea of a rigorous study for the treatment on dogs, she searched for an expert in canine skin allergies and DeBoer's name was at the top of the list. He seemed a natural fit -- a world expert in the area who worked at University of Wisconsin-Madison, where both she and her father had gone to medical school.

Unfortunately, DeBoer "was extremely skeptical, and he basically told me no," she says. "I was very disappointed, and kept trying to persuade him this was a good research project." The two agreed on a pilot study of 10 dogs. "If it failed, it wasn't worth pursuing," she says. "But I think much to his surprise, it actually worked."

The outcome, Morris says, "was the study he is going to present in Vancouver."

Morris has licensed the technology to Heska Corp., whose CEO, Robert Grieve, is a former professor at the School of Veterinary Medicine.

With data in hand, DeBoer has overcome his skepticism. Although the drops must be given once or twice a day for at least several months, they have major advantages, he says. "A lot of owners are needle-shy, and would never consider giving allergy shots, and may not even have the dog evaluated for that reason. Now there is an option that is very user-friendly."

And what do the dogs think? "The drops have a slightly sweet flavor, so most dogs actually like them," says DeBoer. "Owners say their dogs consider them a treat and run toward them when they hear the bottle being opened. With the needle, they learn to run away."

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The above story is reprinted from materials provided by University of Wisconsin-Madison. The original article was written by David Tenenbaum.

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Nunavik sled dogs need first aid and care too

ScienceDaily (June 1, 2012) — In Nunavik, there are many dogs -- sled dogs, pets, and strays -- but no veterinarian, so the University of Montreal International Veterinary Group has given Andréanne Cléroux, a veterinary student, the mandate to design and deliver a first aid guide for dogs in northern Quebec. "The problem relates mainly to animal health care, immunization, and dog population control," Cléroux explains. "We wanted to create a guide that would provide basic tools for pet owners so they can provide care to their animal while waiting to contact the remote veterinary consultation service to get advice from a veterinarian at the CHUV (University of Montreal Veterinary Hospital)."

The initiative is part of the Support project in veterinary public health and animal health in Nunavik, which began in 2008 with the creation of the remote veterinary consultation service.

Last year, Cléroux spent a month writing the guide before flying to Nunavik. During her one-week stay, she presented a draft of her work to several inhabitants of the town of Kuujjuaq. She was accompanied by the junior college student Emaly Bibeau Jonas, who provided interpretation between Inuktitut and French. "Through their comments, I was able to rework the guide to make it more simple, concise, and user-friendly," says Cléroux, who was supervised by the Faculty of Veterinary Medicine's Dr. Denise Bélanger, Dr. Cécile Aenishaenslin, and Dr. Josiane Houle.

The challenge, she notes, was to produce a manual that would address both those unfamiliar with animal health care and those who already have more advanced knowledge, such as dog sled drivers. "Dog mushers are great for recognizing and treating all kinds of medical conditions," says Cléroux.

With accompanying photographs, the guide covers everything from vaccination schedules, drug administration, and care of newborns, to sterilization, zoonotic diseases, fractures, and bandaging methods.

Cléroux has also created a first aid kit that includes all the necessary material to provide the care described in the manual. "At the moment, there is only one kit available at the Makivik Corporation research center in Kuujjuaq. Our goal is to distribute one kit to each of the 14 communities in Nunavik." This month, she'll be travelling once again north of the 55th parallel to deliver copies of the official version of the guide to dog owners in Kuujjuaq. She will do the same in the communities of Quaqtaq and Puvirnituq, while providing first aid kits. "We will evaluate their use by the residents and then decide how to proceed with the other villages," she says. "I hope our work will increase people awareness of veterinary public health issues and animal health, and that our tools will encourage them to promote animal health and care."

Vaccination campaign Rabies is an often-cited problem in Nunavik. "It's an endemic problem. There are reported cases every year," notes Cléroux. The ministère de l'Agriculture, des Pêcheries et de l'Alimentation du Québec (MAPAQ) visits the communities in Hudson Bay and Ungava Bay to conduct annual vaccination campaigns. They provide basic and antirabies vaccines. Local vaccinators are also present at other times of the year. "There is still room for improvement, but we must recognize that vaccination is more widespread than before," says Cléroux.

She experienced this first hand during her stay. At the invitation of MAPAQ, she organized a vaccination clinic, which to her surprise, drew dozens of people. "We saw 120 dogs and two cats in one afternoon!" she recounts, still amazed. "The children were leaning over our shoulders to watch us work and each had a story to tell."

This experience was "extremely rewarding" for the student. "I would like to continue working in these communities. I could go there from time to time to participate in immunization clinics or other projects that focus on animal and public health."

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Too dog tired to avoid danger: Like humans, dogs engage in riskier behaviors when their self-control is depleted

ScienceDaily (Apr. 2, 2012) — Like humans, dogs engage in riskier behaviors when their self-control is depleted.

How do dogs behave when their ability to exert self-control is compromised? Are they more likely to approach dangerous situations or stay well away? According to a new study by Holly Miller, from the University of Lille Nord de France, and colleagues, dogs that have 'run out' of self-control make more impulsive decisions that put them in harm's way. The work was just published online in Springer's Psychonomic Bulletin & Review.

To avoid danger, people often exert self-control over their behavior. When they do not and they behave more impulsively, they may unintentionally put themselves in dangerous situations e.g. pedestrians jaywalk across busy streets, children stick objects into electrical outlets, and teenagers join dangerous gangs. Miller and colleagues' work is the first to demonstrate that this phenomenon of 'self-control depletion' also has significant behavioral implications in animals: mentally fatigued dogs do not think straight and are more likely to inadvertently subject themselves to risks that may result in physical harm.

The researchers recruited ten dogs and trained them to sit still for ten minutes, thereby exerting self-control; or not, by putting them in a cage where they were free to move around. Afterwards, the dogs were walked into a room in which a barking, growling dog was caged. The dogs spent a total of four minutes in the room but were free to choose where in the room they spent their time. Although approaching the other dog was the natural response for the dogs, it was also the riskier choice.

Those dogs who had exerted self-control by sitting still beforehand spent more time in close proximity to the aggressive dog compared with those dogs who had not exerted self-control (i.e. the caged dogs) -- 59 percent compared to 42 percent. These results show that initial self-control exertion results in riskier and more impulsive decision making by dogs.

Miller and team conclude: "The present research provides evidence that the phenomenon of self-control depletion, once believed to be uniquely human, can be found in dogs. Using work in animals may provide a greater insight into the physiological and neurobiological processes that affect self-control."

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Holly C. Miller, C. Nathan DeWall, Kristina Pattison, Mikaël Molet, Thomas R. Zentall. Too dog tired to avoid danger: Self-control depletion in canines increases behavioral approach toward an aggressive threat. Psychonomic Bulletin & Review, 2012; DOI: 10.3758/s13423-012-0231-0

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A number of environmental factors can affect the incidence of hip dysplasia in dogs

ScienceDaily (Mar. 26, 2012) — Hip dysplasia (HD) in dogs is affected to a larger degree than previously believed by the environment in which puppies grow up. It is particularly during the period from birth to three months that various environmental factors appear to influence the development of this disease. During the puppy stage, preventive measures can therefore be recommended with a view to giving dogs disposed to the condition a better quality of life.

Randi I. Krontveit's doctoral research has studied the incidence of HD in four breeds of dog in Norway and examined factors in the environment where the dogs grew up that can have an affect on the number of cases. HD is a genetic disease which also occurs in several other species. Dogs are not born with HD, but genetically disposed puppies can develop varying degrees of HD. The degree of HD has an affect on when the dogs show symptoms and on how long they live.

Five hundred privately owned dogs participated in the study and the four breeds investigated were the Newfoundland, the Labrador Retriever, the Leonberger and the Irish Wolfhound. The environment in which the dogs were born and grew up was registered by means of questionnaires filled out by the breeder and the new owner, and by examinations carried out by veterinary surgeons.

Findings from previous experiments and studies from other countries have indicated that rapid growth and a high body weight are factors that increase the likelihood of developing HD. Randi I. Krontveit's research has shown that rapid growth and high body weight in the first year of the puppies' life did not result in an increased risk of HD. On the contrary, she found that the breed that had the slowest growth rate -- the Newfoundland -- had the highest incidence of HD (36%). The Irish Wolfhound had the lowest incidence of HD (10%), yet had the fastest rate of growth.

Puppies usually live with their mother at the breeder's for the first eight weeks of their life. Several factors related to the living conditions at the breeder's were shown to have an influence on the incidence of HD. Puppies born in the spring or summer and at breeders who lived on a farm or small holding, had a lower risk of developing HD. After about eight weeks, the puppies began life with their new owner. The opportunity to exercise daily in parks up until the age of three months reduced the risk of HD, whereas the daily use of steps during the same period increased the risk. Overall, it would appear that daily exercise out in gently undulating terrain up until the age of three months gives a good prognosis when it comes to preventing HD.

The dogs in this study were followed up until they reached 10 years of age by means of annual questionnaires filled out by the owner. Dogs seriously affected by HD were put down earlier than dogs with a milder form of the disease. This was particularly the case for Newfoundlands and Leonbergers. HD did not have such a large affect on the longevity of Labrador Retrievers or Irish Wolfhounds. Serious and moderate degrees of HD increased the risk of symptoms such as limping and hip pain and these symptoms occurred earliest in Newfoundlands. The Labrador Retriever was the breed in which symptoms appeared latest in life. Varied exercise had a positive effect and dogs that exercised on a daily basis on a lead and running free in different types of terrain were free of symptoms longer than dogs that were less active.

Based on the findings of this doctoral research, preventive measures related to early canine life can be recommended. If HD in its most serious forms can be prevented, the life quality of dogs will be improved.

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Disagreeable people prefer aggressive dogs, study suggests

ScienceDaily (May 22, 2012) — Aggressive dog ownership is not always a sign of attempted dominance or actual delinquency. A study carried out at the University of Leicester's School of Psychology has found that younger people who are disagreeable are more likely to prefer aggressive dogs, confirming the conventional wisdom that dogs match the personality of their owners.

Researchers found that low Agreeableness was the best predictor of a preference for those dogs seen as more aggressive, such as bull terriers or boxers. Individuals low in Agreeableness are typically less concerned with others' well-being and may be suspicious, unfriendly and competitive.

However, the study found no link between liking an aggressive dog and delinquent behaviour, or the possibility that liking an aggressive dog is an act of 'status display' to show off or attract romantic partners.

Dr Vincent Egan, lead researcher on the study, said: "This type of study is important, as it shows assumptions are not the whole picture. It is assumed owners of aggressive dogs (or dogs perceived as aggressive) are antisocial show-offs. But we did not find persons who expressed a preference for aggressive dogs had committed more delinquent acts, or reported showing off more.

"However, we did find a preference for a dog with an aggressive reputation was related to being younger and being lower in Agreeableness (i.e., being less concerned with the needs of others, and being quicker to become hostile)."

The study looked at the reasons why some people prefer aggressive dog breeds. Professor Egan explained:

"A lot of human behaviour involves status display and dominance, and evolutionarily this helps with finding mates. Basic personality also influences a lot of our behaviour. By measuring both at the same time, we could see whether they each had an influence on liking aggressive dogs, or whether one was due to another.

"We were surprised mating effort did not have an influence here, but think it might be because we looked at a wider age range. A preference for a non-aggressive dog may also make a statement about a person; liking a pedigree Labrador or a clipped Poodle may be as much a statement as having a pit-bull with a studded collar."

In the study, participants indicated their preference for different types of dogs, and filled in personality tests. The dogs were independently rated according to how aggressive people perceived them to be. Bull terriers were rated as most aggressive, followed by boxers; retrievers and cocker spaniels were seen as least aggressive.

Analysing the findings, the research team found that certain personality factors indicated a preference for dogs perceived to be more aggressive. Low agreeableness and higher conscientiousness were related to a preference for aggressive dog breeds. Younger people were also more likely to prefer the aggressive breeds.

Surprisingly, the results indicated a small effect suggesting that those who liked aggressive dogs showed signs of conscientiousness - being careful, reliable and thoughtful about their actions. This contradicts the perception that owners of aggressive dogs are always irresponsible.

Dr Egan said: "These results with conscientiousness were unexpected, but the effect is a small one, and needs to be repeated in a different group of people. Studies of this kind tend to only look at a restricted age ranges, which may exaggerate findings which do not occur across the entire lifespan, so we believe a stereotype is always true, whereas it may only be true under certain conditions. Our study employed a broader age range.

"We were surprised to find a small association between a preference for aggressive dogs and greater Conscientiousness (i.e., valuing and following rules). However, dogs also prefer rules and firm boundaries themselves. We speculate that cheap dog-training classes would be enjoyable and beneficial for both dog and owner."

The findings were published last week in the journal Anthrozoos.

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Vincent Egan, Jason MacKenzie. Does Personality, Delinquency, or Mating Effort Necessarily Dictate a Preference for an Aggressive Dog? Anthrozoos: A Multidisciplinary Journal of The Interactions of People & Animals, 2012; 25 (2): 161 DOI: 10.2752/175303712X13316289505305

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Veterinarians find infections faster by monitoring blood compound; Blood test for dogs could lead to similar human test

ScienceDaily (Dec. 6, 2011) — In pets and people, the time it takes to diagnose an infection may mean life or death. Now, a University of Missouri veterinarian is identifying ways to diagnose pet infections in approximately a third of the current diagnosis time. The resulting test could be used eventually for humans.

"Infections can be difficult to diagnose, and many veterinarians have to send samples to a lab and wait three days or more as the lab attempts to grow a culture," said Amy DeClue, assistant professor of veterinary internal medicine in the MU College of Veterinary Medicine. "Meanwhile, the infection continues to spread each day that veterinarians wait on lab results, which is detrimental to the patient. In extreme infections, called sepsis, more than half of patients die. My group has been evaluating different blood biomarkers that could give a quick and accurate indication of infection, and we believe we've found a biomarker that will only require a simple blood test."

DeClue and her colleagues found that measuring the amount of the blood biomarker N-terminal portion of pro C-type natriuretic peptide (NT-pCNP) is a good indication of infection, and the same is true in humans. Working with collaborators at Veterinary Diagnostics Institute, DeClue hopes to develop a portable bedside test that veterinarians could use to quickly test patients for infection and ultimately target a better cure.

"In animal and human medicine, one goal is to reduce the amount of antibiotics used in treatment, to reduce bacterial resistance to antibiotics," DeClue said. "If successful, future tests could help veterinarians tailor treatment to the specific problem and reduce antibiotic use."

"The systems in dogs and people are very applicable to each other, so whatever biomarkers we find in dogs could also benefit people," DeClue said.

DeClue has tested several biomarkers for infection in dogs. "Evaluation of serum NT-pCNP as a diagnostic and prognostic biomarker for sepsis in dogs" was published in the May-June issue of the Journal of Veterinary Internal Medicine and "Plasma nitrate/nitrite concentrations in dogs with naturally developing sepsis and non-infectious forms of the systemic inflammatory response syndrome," was published in the November issue of the journal Veterinary Record. Co-authors include Kara Osterbur, a graduate student and emergency and critical care resident in the MU College of Veterinary Medicine.

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A.E. DeClue, K. Osterbur, A. Bigio, C.R. Sharp. Evaluation of Serum NT-pCNP as a Diagnostic and Prognostic Biomarker for Sepsis in Dogs. Journal of Veterinary Internal Medicine, 2011; 25 (3): 453 DOI: 10.1111/j.1939-1676.2011.0713.xK. Osterbur, Z. Whitehead, C. R. Sharp, A. E. DeClue. Plasma nitrate/nitrite concentrations in dogs with naturally developing sepsis and non-infectious forms of the systemic inflammatory response syndrome. Veterinary Record, 2011; 169 (21): 554 DOI: 10.1136/vr.d5137

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Saving dogs with spinal cord injuries

ScienceDaily (Jan. 19, 2012) — Dogs with spinal cord injuries may soon benefit from an experimental drug being tested by researchers at the University of California, San Francisco (UCSF) and Texas A&M College of Veterinary Medicine & Biomedical Sciences -- work that they hope will one day help people with similar injuries.

Funded through a three-year, $750,000 grant from the U.S. Department of Defense, the drug to mitigate damage has already proven effective in mice at UCSF. Now the Texas team will test how it works in previously injured short-legged, long torso breeds of dog like dachshunds, beagles and corgis, who often suffer injuries when a disk in their back spontaneously ruptures, damaging the underlying spinal cord.

About 120 dogs a year that develop sudden onset hind limb paralysis after such injuries are brought to the Small Animal Hospital of Texas A&M University, where they receive surgical and medical treatment similar to that for human spinal cord injury. Now, researchers will test whether the new treatment works on some of these dogs, with their owners' consent.

"It would be phenomenal if it works," said Linda J. Noble-Haeusslein, PhD, a professor in the UCSF departments of Neurological Surgery and Physical Therapy and Rehabilitation Science who designed the intervention. "We are in a unique position of being able to treat a dog population where there are simply no current therapies that could effectively improve their hind limb function."

The new treatment does not seek to regrow injured pathways in the spinal cord. Instead, it aims to mitigate damage secondary to the spinal cord injury. Most spinal cord injuries trigger a cascade of chemical reactions in the spinal cord that collectively damage nearby cells and pathways, contributing to functional deficits including hind limb function.

A few years ago, Noble and her UCSF colleague Zena Werb, PhD, showed how blocking the action of one protein found in the spinal cord of mammals can help mice recover from spinal cord injuries. This protein, called matrix metalloproteinase-9, can degrade pathways within the cord and cause local inflammation, leading to cell death.

The injured dogs offer a great opportunity to take the next step on this treatment because their injuries more closely mimic spontaneous human spinal cord injury and, as is the case with humans, no existing treatment has substantially reduced paralysis. Dog in medical device

Dog in medical device

Noble's co-investigator on the new study, Jonathan Levine, DVM, an assistant professor in neurology at Texas A&M University, will treat the dogs through injections of a protein-blocking drug. He will then help the dogs through rehabilitation and assess their recovery. Ongoing studies at UCSF focus on further refining delivery of the drug so as to optimize recovery.

Other researchers have shown that movement can be preserved if as little as 18 percent to 20 percent of the nerve fiber tracts in the spinal cord remain intact.

If successful, the trials in injured dogs may lead to the development of similar treatments for people who suffer spinal cord injuries, Noble said. These are among the most expensive injuries: every person with an injured spinal cord costs the health care system millions of dollars over his or her lifetime.

Such costs often are overshadowed by the tragic and devastating personal price of the injuries, which dramatically alter lives and most often occur in younger people, with long lives in front of them. According to the National Spinal Cord Injury Statistical Center, based at the University of Alabama, Birmingham, most of the 12,000 Americans who suffer spinal cord injuries are between the ages of 16 and 30.

As of this year, some 265,000 people in the United States are living with such injuries, according to the national center. This includes many wounded soldiers who have returned home from war zones.

UCSF is a leading university dedicated to promoting health worldwide through advanced biomedical research, graduate-level education in the life sciences and health professions, and excellence in patient care.

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New epilepsy gene located in dogs

ScienceDaily (Mar. 22, 2012) — A new epilepsy gene for idiopathic epilepsy in Belgian Shepherds has been found in the canine chromosome 37. The research of Professor Hannes Lohi and his group conducted at the University of Helsinki and the Folkhälsan Research Center opens new avenues for the understanding of the genetic background of the most common canine epilepsies. The research also has an impact on the understanding of common epilepsies in humans.

The research is published in the scientific journal PLoS ONE on March 23, 2012.

Epilepsy affects about 1-5% of the human population at some stage of live, and it includes a host of syndromes the age of onset, causes and prognosis of which vary significantly. Based on their basic mechanisms epilepsy syndromes are divided into genetic (idiopathic) epilepsies, structural / metabolic (symptomatic) epilepsies and epilepsies of unknown cause. Symptomatic causes refer to discernible external or structural change, whereas with idiopathic epilepsy there is a strong genetic background. A common denominator between the different syndromes are reoccurring epileptic seizures, which are divided according to an international classification into two main groups -- focal and generalized seizures -- based on clinical symptoms and research findings. About two thirds of the seizures in adults are focal in nature and one third generalized. In children and teenagers the occurrence of generalized forms of epilepsy is greater (ca. 50%).

Identification of the epilepsy gene on process

Genetic factors are estimated to play a role in the development of epilepsy in as many as 40% of epilepsy patients. Several genes affecting the development of symptomatic epilepsies have already been identified, but the genetic background of multifactorial idiopathic epilepsies often remain unknown. Both focal and generalized idiopathic epilepsies occur in Belgian Shepherds. The research group of Professor Hannes Lohi, working in collaboration with Danish, Swedish and American researchers in an EU-funded project, has made a major breakthrough by identifying a chromosome region associated with the most common form of epilepsy in dogs. By comparing the genome of dogs with epilepsy and healthy control dogs a gene region in chromosome 37 was discovered, which if homozygous, increases the risk of epilepsy seven-fold. In addition the research findings indicate that other, still unknown, genetic risk factors may be present in the breed.

The identified region has excellent neurological candidate genes for epilepsy and ongoing follow-up research is aimed to identify the specific gene causing epilepsy. Epilepsy genes have not previously been identified in this chromosome region, so the discovery will reveal an entirely new epilepsy gene in dogs and possibly also in humans. The type of epilepsy occurring in Belgian Shepherds is extremely common in also other breeds and thus the discovery may have an impact on the understanding of the epilepsies in different dog breeds.

"There are only few genes in the identified region and I believe that the ongoing analyses will help us to discover the specific epilepsy gene," says Professor Hannes Lohi who led the research. "This would give us a better understanding of the disease mechanisms and provide us with new diagnostic tools for the disease."

The Research group of Hannes Lohi has begun an extensive gene-sequencing project in which the entire identified chromosome region will be 'read through' with a next-generation sequencing method. By identifying the specific gene mutation an individual's epilepsy risk could be assessed, although the gene mutation may also be common in dogs that never become symptomatic of epilepsy.

Epilepsy is common among Belgian Shepherds

"The identified genomic region is likely to be the strongest single risk factor for epilepsy in Belgian Shepherds, and we are studying an interesting gene variant causing an amino acid change in the protein level. However, this homozygous amino acid change is also present in one fifth of healthy Belgian Shepherds. The research continues in the breed and aims to identify the specific mutation for genetic testing in this loci and possible in other chromosomes. The need for the gene test is urgent since as much as 20% of the dogs in this breed are estimated to have epilepsy," comments the first author of the article Eija Seppälä, PhD.

The age of onset of idiopathic epilepsy in Belgian Shepherds is on average 3 years, although the range varies greatly. A seizure often begins as a focal seizure, and the owner may observe abnormal movement, usually on only one side of the dog's body. At this point the dog often seeks out the owner, drools or vomits. With most Belgian Shepherds the seizure becomes generalized and is accompanied with loss of consciousness and irregular cramping in the limbs. The dog may also urinate or defecate involuntarily.

Earlier gene discoveries of the research group

Epilepsy is the most common disorder of the nervous system in dogs and different types of genetic epilepsies occur in dozens of dog breeds. The research group has previously identified the first epilepsy gene for symptomatic epilepsy, EPM2B, in Miniature Wirehaired Dachshunds, as well as more recently a gene, LGI2, associated with transient idiopathic epilepsy in Lagotto Romagnolos. The group has also participated in the discovery of a gene for symptomatic epilepsy in Tibetan Terriers. Lohi and his research group have built a canine DNA bank in Finland, which currently holds almost 40 000 samples from more than 250 different breeds. The DNA bank has played a major role in the execution of among others the current research to be published in March, 2012.

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Seppälä EH, Koskinen LLE, Gulløv CH, Jokinen P, Karlskov-Mortensen P, Bergamasco L, Baranowska Körberg I, Cizinauskas S, Oberbauer AM, Berendt M, Fredholm M, Lohi H. Identification of a novel idiopathic epilepsy locus in Belgian Shepherds. PloS ONE, 2012 DOI: 10.1371/journal.pone.0033549

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Fungus-induced neurological disease: An underestimated risk for animals and humans?

ScienceDaily (Dec. 15, 2011) — The mould fungus Penicillium crustosum occurs relatively frequently in food and animal fodder stored in temperate conditions. This mould produces powerful neurotoxins, for example penitrem A, which causes symptoms that are difficult to distinguish from those of other neurological diseases. Angel Moldes-Anaya's doctoral research has shown that penitrem A is capable of penetrating the blood-brain barrier and has unveiled the mechanisms behind the neurological effects of the toxin.

Earlier studies have shown that Penicillium mould often occurs in food and fodder stored in temperate conditions. In Norway, there have been examples of waste food considerably contaminated with Penicillium crustosum. This mould produces penitrems which can have serious toxic effects on the nervous system.

Little is known about how these substances affect the body, especially the brain. Even though there are documented cases of penitrem-induced neurological diseases in both humans and animals, diseases of this kind are probably underdiagnosed. This is because the observable symptoms can be mistaken for those of other neurological diseases, methods of analysis are poor and toxicological and pharmacological expertise is unavailable.

During recent years, more than 10 cases of dogs with attacks resembling epilepsy and impaired motor function have been reported at The Norwegian Veterinary Institute. The common denominator was that all the dogs had eaten food or food waste contaminated with the mould fungus Penicillium crustosum. Angel Moldes used chemical and mycological samples from these dogs in his doctoral project, which has studied the effect of penitrem A on the brain and what happens to the toxin in the body.

Angel Moldes has revealed that penitrem A can penetrate the protective blood-brain barrier and therefore reach the brain itself. Furthermore, he has shown that penitrem A is converted in the liver into more water-soluble metabolites which are easier to excrete from the body. These metabolites do not reach the brain and it is therefore probable that penitrem A is solely responsible for the toxic effect.

Moldes has also studied the mechanism underlying the neurological symptoms observed in both dogs and laboratory animals exposed to the toxin. He found that penitrem A has a substantial effect on GABAA receptors in the brain. GABAA receptors are the major therapeutic target of tranquilisers (diazepam) and anesthetics (barbiturates). Penitrem A may have a tranquilising effect on one part of the brain and a cramp-inducing effect on other parts. Moldes has revealed that oxidative stress can be related to the pathological changes found in animals exposed to penitrems, since these toxins increase the production of free radicals that can damage tissue.

Moldes has moreover isolated and determined the structure of a new substance similar to a penitrem which he detected in a biopsy from one of the affected dogs.

M.Tech. Angel Moldes-Anaya defended his doctoral thesis on 8th December 201 at The Norwegian School of Veterinary Science. The thesis is entitled: "Penitrem-induced neurological disease in Norway: clinical cases in dogs. Neuropharmacology and toxicokinetics of penitrem A. Structure elucidation of a novel penitrem analogue."

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New cerebellar ataxia gene identified in dogs

ScienceDaily (June 18, 2012) — Researchers at the University of Helsinki and the Folkhälsan Research Center, Finland, have identified the genetic cause of early-onset progressive cerebellar degeneration the Finnish Hound dog breed. The study, led by Professor Hannes Lohi, revealed a new disease mechanism in cerebellar degeneration. A mutation was identified in the SEL1L gene, which has no previous link to inherited cerebellar ataxias.

This gene find is the first in canine early-onset cerebellar degeneration, and has enabled the development of a genetic test to help eradicate the disease from the breed. At the same time, SEL1L represents a novel candidate gene in human early-onset degenerative ataxias.

The research was published in the scientific journal PLoS Genetics on June 14, 2012.

Inherited ataxias affect both humans and animals. In humans, the hereditary ataxias are a heterogeneous disease group, characterized by cerebellar degeneration and dysfunction. The cerebellum is a part of the brain that is involved in coordination of movement. Degeneration of the cerebellar structures causes ataxia, which is a neurological sign of defective motor coordination that can affect gait, balance, speech and gaze. Approximately 20 known disease-causing genes have been identified in both autosomal recessive and dominant ataxias in humans but the genetic background of canine cerebellar ataxias has remained largely unknown.

The clinical signs of Finnish Hound cerebellar ataxia are present by the age of two months. The affected puppies have difficulty in controlling their leg movements and keeping their balance. The disease progresses rapidly, and in the end eating becomes impossible because of uncontrolled head movements. There is no cure for the disease and affected puppies have to be euthanized.

The research conducted by Professor Lohi and co-workers revealed marked neuronal loss in the cerebellar cortex of affected Finnish Hound puppies. By comparing the genomes of affected and healthy dogs, the cause of the disease was pinpointed to a single nucleotide change in the SEL1L gene. The nucleotide alteration causes an amino acid change in the encoded SEL1L protein.

"The identified ataxia gene is the first early-onset degenerative cerebellar ataxia gene that has been identified in dogs," says professor Hannes Lohi. In addition to Finnish Hounds, cerebellar degeneration has been identified in several other dog breeds.

"The SEL1L gene has not been previously connected to cerebellar ataxias in any species and it represents a novel candidate gene for human early-onset ataxias," Lohi continues. "In fact, we have already screened a small cohort of human patients for possible disease-causing SEL1L mutations."

The gene identification in Finnish Hound dogs reveals a new disease mechanism, which will hopefully shed more light in to the pathogenesis of neuronal degeneration. The amino acid change in SEL1L hits an evolutionary conserved functional domain, and is very likely to affect the normal function of the protein. SEL1L functions in quality control of newly synthesized proteins, in a cell organelle referred to as the endoplasmic reticulum. A failure in the quality control system causes endoplasmic reticulum stress and eventually cell death.

"It is very interesting that although the SEL1L gene is expressed in several different tissues, we only saw pathological changes in the cerebellar cortex of affected dogs. It is known that certain neurons in the cerebellar cortex seem to be very sensitive to endoplasmic reticulum stress, which might offer some explanation to the cerebellum-restricted cell loss," tells M.Sc Kaisa Kyöstilä, the first author of the article. "We were also able to measure increased endoplasmic reticulum stress in the affected puppies' cerebellar cortex, which gives more support to SEL1L as the causative gene in Finnish Hound ataxia," Kyöstilä adds.

Finnish Hound ataxia is a single gene defect, inherited in an autosomal recessive manner. According to the research, 10% of Finnish Hounds carries the recessive ataxia mutation in their genome. A genetic test has been developed for breeding purposes. The test has enabled to identify disease carriers, and when mated with non-carriers, they too can be used in breeding programs. If all carrier dogs were excluded by breeders, the genetic diversity of the breed could be affected. The Finnish Hound ataxia test is offered by a DNA-test laboratory Genoscoper, and is the first test for a native Finnish breed developed by the research group.

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Kaisa Kyöstilä, Sigitas Cizinauskas, Eija H. Seppälä, Esko Suhonen, Janis Jeserevics, Antti Sukura, Pernilla Syrjä, Hannes Lohi. A SEL1L Mutation Links a Canine Progressive Early-Onset Cerebellar Ataxia to the Endoplasmic Reticulum–Associated Protein Degradation (ERAD) Machinery. PLoS Genetics, 2012; 8 (6): e1002759 DOI: 10.1371/journal.pgen.1002759

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Love of a dog or cat helps women cope with HIV/AIDS

ScienceDaily (Jan. 25, 2012) — A spoonful of medicine goes down a lot easier if there is a dog or cat around. Having pets is helpful for women living with HIV/AIDS and managing their chronic illness, according to a new study from the Frances Payne Bolton School of Nursing at Case Western Reserve University.

"We think this finding about pets can apply to women managing other chronic illnesses," said Allison R. Webel, instructor of nursing and lead author of the article, "The Relationship Between Social Roles and Self-Management Behavior in Women Living with HIV/AIDS," which appears in the online journal Women's Health Issues.

Webel set out to better understand how women manage their HIV/AIDS and stay on track to take their medications, follow doctors' orders and live healthy lifestyles. She conducted 12 focus groups with 48 women to find out what they did to stay healthy. The women had an average age of 42, about 90 percent had children, and more than half were single.

During the focus groups, six predominant social roles emerged that helped and hindered these women in managing their illness: pet owner, mother/grandmother, faith believer, advocate, stigmatized patient, and employee. All roles had a positive impact except stigmatized patient, which prevented women from revealing their illness and seeking out appropriate supports.

"Much information is available about the impact of work and family roles, but little is known about other social roles that women assume," Webel said.

Being a pet owner was an important surprise, added Webel, who collaborated with co-author Patricia Higgins, a professor of nursing at Case Western Reserve University.

"Pets -- primarily dogs -- gave these women a sense of support and pleasure," Webel said.

When discussing the effect their pets have on their lives, the women weighed in. "She's going to be right there when I'm hurting," a cat owner said. Another said: "Dogs know when you're in a bad mood…she knows that I'm sick, and everywhere I go, she goes. She wants to protect me."

The human and animal bond in healing and therapy is being recognized, Webel said, as more animals are visiting nursing homes to connect to people with dementia or hospitals to visit children with long hospital stays.

Being a pet owner is just one social aspect of these women's lives. "We found the social context in which this self-management happens is important," Webel said.

Another strong role to emerge was advocate. Participants wanted to give back and help stop others from engaging in activities that might make them sick, the researchers report.

While roles as mothers and workers are well documented, "less-defined social roles also have a positive impact on self-management of their chronic illness," Webel said.

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If your dog is aggressive, maybe it is in pain

ScienceDaily (June 13, 2012) — Dogs can sometimes suffer sudden episodes of aggression without their owners understanding why. But, in many cases, the cause of these attacks can be pain that has never been diagnosed or treated. For the first time the study describes the characteristics of this irritability, which can make dogs violent and increase aggression in already conflictive individuals.

There are many factors that explain aggression in dogs: the conditions of the mother during gestation, the handling of the puppy in the neonatal phase, the age at weaning, the experiences of the animal during the socialising phase, diet, exercise, genetics and learning techniques based on active punishment during adulthood. However, aggressive behaviour also arises from the presence of pathologies and pain in the dog.

Between 2010 and 2011 a team of researchers from the department of Animal and Food Science at the Autonomous University of Barcelona (UAB) in Spain analysed the aggression problems of 12 dogs (Giant schnauzer, Irish setter, Pit-bull, Dalmatian, two German shepherds, Neapolitan Mastiff, Shih-tzu, Bobtail, Catalan Sheepdog, Chow-chow and Doberman) who were brought to the UAB's Veterinary Hospital by their owners.

"All (eleven males and one female) were diagnosed as having aggression caused by pain. Out of the 12 studied, eight had suffered a hip dysplasia," as was outlined by Tomás Camps, lead author of the study that was published in the Journal of Veterinary Behavior and researcher at the Animal Nutrition and Welfare Service of the UAB.

Scientists identified the most frequent circumstances in which dogs were aggressive, the most characteristic positions, the most frequent target of attacks and if they were impulsive or, in other words, whether or not they showed signs before an imminent attack.

The study shows that dogs that were already aggressive for other reasons before the onset of pain attacked their owners more intensely and frequently when food was taken away, when they were moved from their rest area or when they were made to do something. Animals displayed aggression in the same situations (or nearly) as those that were already aggressive.

On the other hand, "dogs that had never been aggressive before the onset of pain began to behave in this way in situations were an attempt is made to control them," points out Camps.

In addition, the study shows that those dogs were more impulsive or, in other words, attacked with no prior warning in the form of growls, for instance. The research team states that "if the pet is handled when in pain, it will quickly act aggressively to avoid more discomfort without the owner being able to prevent it."

Diagnosing hip dysplasia

Canine hip dysplasia affects more than 40% of Golden Retrievers, Labradors and Rottweillers and is a hereditary and degenerative bone disorder that affects the joint connecting the hip and the femoral head. In general, it can affect any breed of large dog but is less frequent is small breeds.

The new study suggests that the pain produced by hip dysplasia is a key factor in the risk of large dogs becoming aggressive. But the problem begins when the dog experiences periods of little pain and the illness is not diagnosed on time.

The researchers have reassessed the importance of diagnosis and treatment of pain since, according to Camps, "it can cause aggression or worsen aggression problems."

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Tomás Camps, Marta Amat, Valentina M. Mariotti, Susana Le Brech, Xavier Manteca. Pain-related aggression in dogs: 12 clinical cases. Journal of Veterinary Behavior: Clinical Applications and Research, 2012; 7 (2): 99 DOI: 10.1016/j.jveb.2011.08.002

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Dogs read our intent

ScienceDaily (Jan. 5, 2012) — Dogs pick up not only on the words we say but also on our intent to communicate with them, according to a report published online in the Cell Press journal Current Biology on January 5.

The findings might help to explain why so many people treat their furry friends like their children; dogs' receptivity to human communication is surprisingly similar to the receptivity of very young children, the researchers say.

"Increasing evidence supports the notion that humans and dogs share some social skills, with dogs' social-cognitive functioning resembling that of a 6-month to 2-year-old child in many respects," said József Topál of the Hungarian Academy of Sciences. "The utilization of ostensive cues is one of these features: dogs, as well as human infants, are sensitive to cues that signal communicative intent."

Those cues include verbal addressing and eye contact, he explained. Whether or not dogs rely on similar pathways in the brain for processing those cues isn't yet clear.

Topál's team presented dogs with video recordings of a person turning toward one of two identical plastic pots while an eye tracker captured information on the dogs' reactions. In one condition, the person first looked straight at the dog, addressing it in a high-pitched voice with "Hi dog!" In the second condition, the person gave only a low-pitched "Hi dog" while avoiding eye contact.

The data show that the dogs were more likely to follow along and look at the pot when the person first expressed an intention to communicate.

"Our findings reveal that dogs are receptive to human communication in a manner that was previously attributed only to human infants," Topál said.

As is often the case in research, the results will undoubtedly confirm what many dog owners and trainers already know, the researchers say. Notably, however, it is the first study to use eye-tracking techniques to study dogs' social skills.

"By following the eye movements of dogs, we are able to get a firsthand look at how their minds are actually working," Topál said. "We think that the use of this new eye-tracking technology has many potential surprises in store."

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The above story is reprinted from materials provided by Cell Press, via EurekAlert!, a service of AAAS.

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Erno Téglás, Anna Gergely, Krisztina Kupán, Ádám Miklósi, József Topál. Dogs' Gaze Following Is Tuned to Human Communicative Signals. Current Biology, 2012; DOI: 10.1016/j.cub.2011.12.018

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Gene therapy cures retinitis pigmentosa in dogs

ScienceDaily (Jan. 23, 2012) — Members of a University of Pennsylvania research team have shown that they can prevent, or even reverse, a blinding retinal disease, X-linked Retinitis Pigmentosa, or XLRP, in dogs.

The disease in humans and dogs is caused by defects in the RPGR gene and results in early, severe and progressive vision loss. It is one of the most common inherited forms of retinal degeneration in man.

"Every single abnormal feature that defines the disease in the dogs was corrected following treatment," said lead author William Beltran, assistant professor of ophthalmology at Penn's School of Veterinary Medicine.

"We were thrilled," said senior author Gustavo Aguirre, professor of medical genetics and ophthalmology at Penn Vet. "The treated cells were completely normal, and this effect resulted from introducing the normal version of the human gene into the diseased photoreceptor cells."

The similarities between humans and dogs, in terms of both eye anatomy, physiology, disease characteristics and positive response to this gene therapy, raise hope for a clear path to human therapies.

Beltran and Aguirre collaborated with Artur Cideciyan and Samuel Jacobson at the Scheie Eye Institute, part of the University of Pennsylvania's Perelman School of Medicine. This achievement results from more than 10 years of close collaboration between the scientists at Penn's veterinary and medical Schools and the University of Florida.

In addition to others at Penn Vet, Scheie and Florida, researchers at the universities of Michigan and Massachusetts and the National Eye Institute at the National Institutes of Health contributed to the research.

The study will be published in the journal Proceedings of the National Academy of Sciences.

The gene therapy approach used takes advantage of a viral vector -- a genetically modified virus that doesn't cause disease and is unable to divide -- to deliver the therapeutic RPGR gene specifically to diseased rods and cones. In the absence of treatment, these cells malfunction and progressively die.

The research team has previously successfully applied a similar approach to two other heritable vision disorders that occur in both humans and dogs: Leber congenital amaurosis and achromatopsia. The present study was more challenging, as it was necessary to target both main classes of photoreceptor cells.

While the exact disease mechanism of the RPGRform of XLRP is still unknown, the researchers were able to successfully treat dogs with two different RPGR mutations. The mutations disrupt photoreceptors in different ways, but both ultimately cause them to become useless for vision. While this form of blindness is rare in dogs, it is common in humans. Patients with XLRP usually begin to lose night vision as children and become almost totally blind by middle age.

This is the first proof that this condition is treatable in an animal model; a single subretinal injection administered to the diseased dogs led to functional and structural recovery. The dogs' recovery was assessed using a variety of methods that are used clinically in patients, such as electroretinography and optical coherence tomography.

The researchers feel the results are promising and relevant for translation to the clinic.

"We are intervening to treat both classes of photoreceptor cells, rods and cones, and that has never been done before in a large animal model," Beltran said. "And not only can we prevent the disease onset but also restore the remaining photoreceptors cells to normal once the disease is ongoing."

While the ability to repair both rods and cones was itself a first, the research team went further, showing that its treatment also repaired the photoreceptor connections to other retinal neurons that eventually send visual signals to the brain, another first.

"This not only provides hope for reversing XLRP but potentially for any form of photoreceptor degeneration," Aguirre said. "Altered inner retinal wiring is a common feature for these diseases that has been considered irreversible.

"The study required a combination of genetic tools and surgical technique to make sure the therapy targeted only the diseased cells. The viral vector had to be injected in the sub-retinal space so as to be in close proximity to the photoreceptors. Likewise, you need to ultimately deliver the therapy to the right location of the retina," Aguirre said.

"In the human disease, careful characterization of the areas of the retina that need to be treated is going to be critical for therapy to succeed in the clinic," Cideciyan said.

The genetic aspect of the viral vector used in this study involved a double safeguard. The first safety feature was to use a viral vector that is known to predominantly target both rods and cones but not other cells. The second safeguard involved attaching the healthy RPGRgene to a "promoter," a piece of genetic code that would "switch on" the gene only if the virus penetrated the correct cell.

Selecting the right promoter was critical; the lead researchers at the University of Florida, William W. Hauswirth and Alfred S. Lewin, had to find one that that would be turned on exclusively in rods and cones. This way, even if the virus made its way to a non-photoreceptor cell, that cell would not start activating the RPGR gene.

That both the promoter and the RPGRgene it activates are taken from humans is a strong sign that the treatment may be translatable to patients.

"While there is still much work to do to assess long-term efficiency and safety with this approach, there is hope that this vector and knowledge could be used in a few years to treat the many patients losing vision from XLRP," Jacobson said.

In addition to Beltran, Aguirre, Cideciyan, Jacobson and Hauswirth, the research was conducted by Sem Genini and Simone Iwabe of Penn Vet; Alejandro J. Román, Malgorzata Swider, Alexander Sumaroka and Tomas S. Alemán of Scheie; Alfred S. Lewin, Diego S. Fajardo, Vince A. Chiodo, Wen-Tao Deng and Sanford L. Boye of Florida; Hemant Khanna of Michigan and Massachusetts; and Anand Swaroop of Michigan and the National Eye Institute.

The research was supported by the National Institutes of Health, the Foundation Fighting Blindness, a Fight for Sight Nowak family grant, the Midwest Eye Banks and Transplantation Center, the Macula Vision Research Foundation, the Van Sloun Fund for Canine Genetic Research, Hope for Vision, and Research to Prevent Blindness.

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William A. Beltran, Artur V. Cideciyan, Alfred S. Lewin, Simone Iwabe, Hemant Khanna, Alexander Sumaroka, Vince A. Chiodo, Diego S. Fajardo, Alejandro J. Román, Wen-Tao Deng, Malgorzata Swider, Tomas S. Alemán, Sanford L. Boye, Sem Genini, Anand Swaroop, William W. Hauswirth, Samuel G. Jacobson, and Gustavo D. Aguirre. Gene therapy rescues photoreceptor blindness in dogs and paves the way for treating human X-linked retinitis pigmentosa. PNAS, January 23, 2012 DOI: 10.1073/pnas.1118847109

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Ancient domesticated dog skull found in Siberian cave: 33,000 years old

ScienceDaily (Jan. 24, 2012) — A 33,000-year-old dog skull unearthed in a Siberian mountain cave presents some of the oldest known evidence of dog domestication and, together with an equally ancient find in a cave in Belgium, indicates that modern dogs may be descended from multiple ancestors.

If you think a Chihuahua doesn't have much in common with a Rottweiler, you might be on to something.

An ancient dog skull, preserved in a cave in the Altai Mountains of Siberia for 33,000 years, presents some of the oldest known evidence of dog domestication and, together with equally ancient dog remains from a cave in Belgium, indicates that domestication of dogs may have occurred repeatedly in different geographic locations rather than with a single domestication event.

In other words, man's best friends may have originated from more than one ancient ancestor, contrary to what some DNA evidence previously has indicated.

"Both the Belgian find and the Siberian find are domesticated species based on morphological characteristics," said Greg Hodgins, a researcher at the University of Arizona's Accelerator Mass Spectrometry Laboratory and co-author of the study that reports the find.

"Essentially, wolves have long thin snouts and their teeth are not crowded, and domestication results in this shortening of the snout and widening of the jaws and crowding of the teeth."

The Altai Mountain skull is extraordinarily well preserved, said Hodgins, enabling scientists to make multiple measurements of the skull, teeth and mandibles that might not be possible on less well-preserved remains. "The argument that it is domesticated is pretty solid," said Hodgins. "What's interesting is that it doesn't appear to be an ancestor of modern dogs."

The UA's Accelerator Mass Spectrometry Laboratory used radiocarbon dating to determine the age of the Siberian skull.

Radioactive carbon, or carbon-14, is one of three carbon isotopes. Along with naturally occurring carbon dioxide, carbon-14 reaches the surface of Earth by atmospheric circulation, where plants absorb it into their tissues through photosynthesis.

Animals and humans take in carbon-14 by ingesting plants or other animals that have eaten plants. "Carbon-14 makes it into all organic molecules," said Hodgins. "It's in all living things."

"We believe that carbon-14 production is essentially constant over time," said Hodgins. "So the amount of carbon-14 present in living organisms in the past was similar to the levels in living organisms today. When an animal or plant dies, the amount of carbon-14 in its remains drops at a predictable rate, called the radioactive half-life. The half-life of radiocarbon is 5,730 years."

"People from all over the world send our laboratory samples of organic material that they have dug out of the ground and we measure how much carbon-14 is left in them. Based on that measurement, and knowing the radiocarbon half-life, we calculate how much time must have passed since the samples had the same amount of carbon-14 as plants and animals living today."

The researchers use a machine called an accelerator mass spectrometer to measure the amount of radioactive carbon remaining in a sample. The machine works in a manner analogous to what happens when a beam of white light passes through a prism: White light separates into the colors of the rainbow.

The accelerator mass spectrometer generates a beam of carbon from the sample and passes it through a powerful magnet, which functions like a prism. "What emerges from it are three beams, one each of the three carbon isotopes," said Hodgins. "The lightest carbon beam, carbon-12, bends the most, and then carbon-13 bends slightly less and carbon-14 bends slightly less than that."

The relative intensities of the three beams represent the sample's carbon mass spectrum. Researchers compare the mass spectrum of an unknown sample to the mass spectra of known-age controls and from this comparison, calculate the sample's radiocarbon age.

At 33,000 years old, the Siberian skull predates a period known as the Last Glacial Maximum, or LGM, which occurred between about 26,000 and 19,000 years ago when the ice sheets of Earth's last ice age reached their greatest extent and severely disrupted the living patterns of humans and animals alive during that time. Neither the Belgian nor the Siberian domesticated lineages appear to have survived the LGM.

However, the two skulls indicate that the domestication of dogs by humans occurred repeatedly throughout early human history at different geographical locations, which could mean that modern dogs have multiple ancestors rather than a single common ancestor.

"In terms of human history, before the last glacial maximum people were living with wolves or canid species in widely separated geographical areas of Euro-Asia, and had been living with them long enough that they were actually changing evolutionarily," said Hodgins. "And then climate change happened, human habitation patterns changed and those relationships with those particular lineages of animals apparently didn't survive."

"The interesting thing is that typically we think of domestication as being cows, sheep and goats, things that produce food through meat or secondary agricultural products such as milk, cheese and wool and things like that," said Hodgins.

"Those are different relationships than humans may have with dogs. The dogs are not necessarily providing products or meat. They are probably providing protection, companionship and perhaps helping on the hunt. And it's really interesting that this appears to have happened first out of all human relationships with animals."

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The above story is reprinted from materials provided by University of Arizona. The original article was written by Shelley Littin, NASA Space Grant intern, University Communications.

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Nikolai D. Ovodov, Susan J. Crockford, Yaroslav V. Kuzmin, Thomas F. G. Higham, Gregory W. L. Hodgins, Johannes van der Plicht. A 33,000-Year-Old Incipient Dog from the Altai Mountains of Siberia: Evidence of the Earliest Domestication Disrupted by the Last Glacial Maximum. PLoS ONE, 2011; 6 (7): e22821 DOI: 10.1371/journal.pone.0022821

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Dogs succeed while chimps fail at following finger pointing: Chimpanzees have difficulty identifying object of interest based on gestures

ScienceDaily (Feb. 8, 2012) — Dogs are better than chimps at interpreting pointing gestures, according to a study published in the online journal PLoS ONE.

Katharina Kirchhofer, of the Max Planck Institute for Evolutionary Anthropology in Germany, led a team in the investigation of 20 chimps and 32 dogs presented with the same task: retrieving an object the experimenter wanted, as indicated by the experimenter pointing. The researchers found that the dogs performed well, but the chimps failed to identify the object of interest.

These results emphasize the difference in chimp response to human gaze, which they have been shown to be good at following, versus gestures.

"The fact that chimpanzees do not understand communicative intentions of others, suggests that this may be a uniquely human form of communication. The dogs however challenge this hypothesis. We therefore need to study in more detail the mechanisms behind dogs' understanding of human forms of communication," says Dr. Kirchhofer.

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Katharina C. Kirchhofer, Felizitas Zimmermann, Juliane Kaminski, Michael Tomasello. Dogs (Canis familiaris), but Not Chimpanzees (Pan troglodytes), Understand Imperative Pointing. PLoS ONE, 2012; 7 (2): e30913 DOI: 10.1371/journal.pone.0030913

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