The Chug is not a purebred dog. It is a cross between the Chihuahuaand the Pug. The best way to determine the temperament of a mixed breed is to look up all breeds in the cross and know you can get any combination of any of the characteristics found in either breed. Not all of these designer hybrid dogs being bred are 50% purebred to 50% purebred. Many of the health problems in Chugs aren't apparent in puppyhood, but by adopting an adult dog, most of them can be ruled out. In addition, Chugs can live 15 or more years, so an adult dog will still be a part of your family for a long time to come. Puppy or adult, take your Chug to your veterinarian soon after adoption.