Don't be fooled- they only get their puppies from puppy mills- please do your research, good breeders do not sell to pet stores!
A puppy mill is a large-scale commercial dog breeding operation where profit is given priority over the well-being of the dogs. Unlike responsible breeders, who place the utmost importance on producing the healthiest puppies possible, breeding at puppy mills is performed without consideration of genetic quality. This results in generations of dogs with unchecked hereditary defects.
Puppy mill puppies are typically sold to pet shops—usually through a broker, or middleman—and marketed as young as eight weeks of age. The lineage records of puppy mill dogs are often falsified.
http://www.aspca.org/fight-animal-cruelty/puppy-mills/what-is-a-puppy-mill.aspx
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