Small dogs live longer: scientists made an unexpected discovery
Small dogs live longer, and this is no longer a hypothesis but a proven fact. At least, that's what scientists from the University of Adelaide believe. They claim to have found the real reason for the shorter life expectancy of large breeds.
It's all about one of the most serious diseases to which large dogs are more prone. The Daily Mail provided more details.
Researchers from the University of Adelaide analyzed the most common causes of death in 164 dog breeds of different sizes. Larger animals have a higher predisposition to oncology.
"The natural defense against cancer does not keep up with the selective breeding of massive dogs. When we analyzed these datasets, we found that larger dogs are more likely to die of cancer at a younger age compared to small dogs," said study author Dr. Jack da Silva.
Everything is explained by a sad trend: the higher the average body weight of a dog, the higher the likelihood that the animal will get cancer.
"There is a theory that the connection between a dog's body size and its life expectancy may be caused by an evolutionary lag in the body's defense against cancer, which is unable to keep up with the rapid and recent breeding of larger dogs," da Silva said.
Some statistics: a Yorkshire Terrier with an average weight of 3 kg can live up to 16 years. The weight of the English Mastiff reaches 113 kg, and it usually lives for 6-10 years.
The study was published in The American Naturalist. The shorter life expectancy of large dogs is also explained by a higher metabolic rate and a tendency to serious illnesses. The larger the dog, the more likely it is to develop cancer at a young age.
Artificial breeding and the development of new breeds have led to animals evolving to large sizes faster than natural evolution could have allowed.
"If most of the body's resources and energy go into growth and reproduction, you can't also invest them in cellular repair and cancer protection. Big dogs did not have time to develop better cancer defense mechanisms," Dr. da Silva said.
Earlier, OBOZREVATEL told you about the rarest dog breeds that may soon disappear forever.