>Several studies have shown that mixed-breed dogs have a health advantage over pure-bred dogs. A German study finds that "Mongrels require less veterinary treatment".[20] Studies in Sweden have found that "Mongrel dogs are less prone to many diseases than the average purebred dog"[21] and, referring to death rates, “Mongrels were consistently in the low risk category”.[22] Data from Denmark also suggest that mixed breeds have higher longevity on average compared to purebreeds. [23] A British study showed similar results but a few breeds (notably Jack Russell Terriers, Miniature Poodles and Whippets) lived longer than mixed breeds.[24]
>In one landmark study, the effect of breed on longevity in the pet dog was analyzed using mortality data from 23,535 pet dogs. The data were obtained from North American veterinary teaching hospitals. The median age at death was determined for pure and mixed breed dogs of different body weights. Within each body weight category, the median age at death was lower for pure breed dogs compared with mixed breed dogs. The median age at death was "8.5 years for all mixed breed dogs, and 6.7 years for all pure breed dogs" in the study.[25]
>In 2013, a study found that mixed breeds live on average 1.2 years longer than pure breeds, and that increasing body-weight was negatively correlated with longevity (i.e. the heavier the dog the less its lifespan).
Mongrel power.
