“In recent years, the dog has become one of the most important animals for researchers seeking to understand the biological background of complex traits,” said Dr. Enikő Kubinyi, an ethologist at Eötvös Loránd University in Budapest, Hungary. Previously, dogs were not considered a good model for studies on animal behavior, as they were thought to be an “artificial species” that had been shaped by humans. But this view has changed in the last 25 years, says Dr. Kubinyi. A key factor has been his university’s Family Dog Project, founded in 1994 on the principle that the family home is the natural environment of dogs due to their adaptations over many thousands of years to living with people.
Now one of the largest canine research groups in the world, the initiative was expanded in 2016 with the Elder Family Dog Project, or EVOLOR, to specifically look at cognitive aging. And Dr. Kubinyi, who is a principal investigator on the project, says that dogs have a number of key advantages as a model of aging for humans over apes and traditional laboratory animals like rodents. To begin with, living with people means that dogs experience nearly identical social and environmental influences on a daily basis. They are also susceptible to many similar age-related diseases, such as a form of Alzheimer’s-like dementia, that mice do not develop naturally.
Additionally, the rapid rise of big data and citizen science, in which the general public contributes to scientific projects, means that it has become much easier to get people to volunteer their pets to participate, says Dr. Kubinyi. , and EVOLOR has collected data through behavioral tests and surveys on more than 20,000 dogs. “When we started the project, we established a group of devoted owners who promised to come to the lab several times a year, and we collected longitudinal data on those dogs,” he said.
Aging
Although the final data is still being analyzed, findings during the project further supported the usefulness of dogs as a broad source of information on aging. “Our results support the dog’s potential as a model of cognitive aging and provide insights to improve the quality of life for dogs and owners,” he added. “We found age-related differences in brain activity, cognition, personality, gut microbiome, gene expression, and genetic variants in various aspects similar to human aging …”.
Analyzing behavioral changes in a recent study of 217 Border Collies aged between six months and 15 years, the team, together with the Clever Dog Lab in Austria, found similarities to humans in the dogs’ possession of personality traits. both malleable and stable as they age, along with variable trajectories between traits. For example, dogs’ interest in problem solving tended to increase until middle age, approximately three to six years, before stabilizing, while the search for novelty changed little until middle age and then steadily declined. In contrast, as in humans, personality traits remained fairly stable among dogs: for example, young dogs that were more active tended to remain that way when they were older.
The team has also found that older dogs seem to experience a similar “positivity effect” as older people, reacting less to negative sounds like crying than positive sounds like laughing. “I have a 13 1/2 year old Lab, and when I say ‘come here’, he just doesn’t listen to me. But when he hears me moving his food box, he comes immediately, “Dr. Kubinyi said.” Old dogs seem to hear what they want to hear … In humans, the elderly are more attuned to positive emotions and less attuned to the negatives “.
Genetic links
In addition to analyzing the behavioral aspects of aging, the project analyzes processes at the molecular level and establishes a basis for understanding the specific underlying neural and genetic links with aging, including through methods such as EEG (electroencephalography), fMRI (functional magnetic resonance imaging). magnetic) and genetic testing. One study supported the analysis of activity patterns in the brain of sleeping dogs as a biomarker of cognitive aging in all species; another found that dogs that performed better on memory tests tended to have lower levels of certain actinobacteria in the gut, mimicking some observations in people with Alzheimer’s disease.
“This is preliminary research, but again there were parallels with human research,” Dr. Kubinyi said, adding that it could also shed light on the best types of diet to keep dogs healthy as they age. And on the genetics side, looking at the complete genome sequence of two 22 and 27 year old mixed breed canines, much older than the average lifespan of a dog of approximately 10 to 13 years, and nicknamed ‘Methuselah dogs’ by the biblical figure of long life. – Researchers identified more than 80,000 novel genetic mutations compared to 850 dogs with a normal life expectancy.
Original article
This article was originally published in Horizon, the EU Research and Innovation Magazine
