The average life expectancy of a dog breed is influenced by numerous factors. Even though race-specific diseases play a role, the reason for a shorter or longer life seems to be far more obvious. Thus, when considering different breeds, smaller dogs usually live much longer than large ones. Researchers from the USA have now cast a glance behind this observation and provide a convincing explanation.
Fast growth causes stress
At Colgate University in New York, researchers Alex Ionescu and Josh Winward focused on the life expectancy of different breeds of dogs. At the center of her work was the question of why big dogs die much earlier than their little relatives. To find out, the researchers examined tissue samples from a total of eighty dogs. Among the animals were both puppies and adult quadrupeds. In the analysis of the tissue samples, the researchers focused mainly on free radicals and those metabolites that point to oxidative stress.
While the content of free radicals in adult dogs was similar in both small and large specimens, there were marked differences in puppies. So the cells of puppies of large dog breeds contained like Irish Wolfhound or mastiff significantly more free radicals than those of Chihuahuas or Pinschers, According to Ionescu and Winward, the reason for this is the faster growth of large breeds. As the metabolism of large dogs is driven to peak performance due to the greatly accelerated growth, oxidative stress, which in turn causes the cells within the body to develop dogs body damaged.