 uh... we've already discussed the large breed dogs don't live as long and if we did a study in ducks and chihuahua mixes we'd be around for twenty years waiting for to see if there was an effect so it's true that uh... from our own research we found that the purebred dogs as Celine mentioned uh... in fact are about on average live about a year shorter than the mixed breed dogs that's not to say that everybody should go out and get a mutt