Science still doesn’t know exactly how long a dog lives on average, because the number varies so much. However, what is known is that large dogs tend to live less than small ones. To better understand the reason behind this, a team of researchers conducted a study that was published in the scientific journal American Naturalist.
The study, conducted by scientists at The University of Adelaide (Australia), suggests that large breeds are more susceptible to cancer, precisely because of selective breeding for size. In all, 164 races were analyzed so that the team could arrive at this discovery.
In practice, the group realized that as the average body weight of the breed increases, the incidence of cancer increases as well. There is still no concrete statement of the reason behind this, but one of the theories is that this relationship may come from an evolutionary delay in the defenses against cancer, unable to keep up with the selective breeding of large dogs.
“The development of breeds larger and smaller than the ancestral gray wolves occurred through changes in the initial growth rate. This may explain the age-dependent minimum mortality rate increasing with breed body size and therefore higher mortality.” age-dependent throughout adult life. The main cause of this mortality is cancer”, points out the study.
The idea of the research is to contribute to studies on aging in humans. In the USA, scientists are currently conducting a project called the Dog Aging Project, which consists of monitoring thousands of elderly dogs to understand whether a drug called rapamycin can help them live longer or if, at least, the drug is capable of keeping these animals longer. healthy and fit as they age.
Source: American Naturalist
