Some people believe mutts are the ultimate health beasts while others insist only purebreds should be allowed to breed.
The biggest venture into this minefield has been undertaken by the University of California-Davis which has investigated over 100,000 purebreds & mutts over a 15-year period (1995-2010).
While this study makes a great effort to understand predispositions of genetic health disorders and tries to compare crossbreeds to purebreds, some aspects would make some statisticians cry.
Strays are often mixed breeds and rescue dogs are rarely screened until something happens in their senior years. Furthermore, irresponsible designer dog breeders often don't perform health testing.
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