I guess I want to comment on a couple things, but this is a sensitive subject and I believe people can easily take things wrong or read more into what is being said... I only hope I can be concise enough that that won't happen with this post.

When people talk about health problems and unknown bloodlines, they generally are talking about purebred dogs who are particularly prone to things, such as German shepherds being prone to hip dysplasia and collies prone to eye problems for example, and when they talk about avoiding this possibility by getting a puppy from a reputable breeder, they are doing that because a lot of these breed-inherent problems tend to be hereditary and passed down through genes and bad breeding. A reputable and responsible breeder will breed to prevent these things as well as certify that they have been tested for that breed-specific problem. It is no guarantee of course that the dog will always be healthy, but there is less a chance of it than getting an unknown purebred pup whose parents may have been from a puppymill and had generations of hereditary disease. I truly don't think anyone actually feels that a shelter or rescue dog is automatically less healthy, and mutts especially are known to be more vigorous! I'm pretty sure Tommy was originally from a puppy mill and I used to worry a lot if he'd have any of the myriad health problems goldens can be prone to come up, but so far he has had a pretty clean bill of health .

I admire and applaud anyone who adopts from a shelter or rescue, my two are both rescues, but I completely understand and have nothing against those who choose to go to a responsible breeder, though I hope they do their homework and make sure the breeder truly is responsible. Glacier stated well what I would consider to be responsible breeding.

In a perfect world there would only be purebred dogs responsibly bred, all with forever homes lined up before leaving their mother's side. I'd sure miss mutts though, I must admit, even though any mutt is the result of irresponsibility. There will always be careless, ignorant, and irresponsible breeders and dog owners though, and a great many of us working hard to keep the dogs from paying the price of their actions. As opposed to these irresponsible, ignorant, or greedy puppymillers, responsible breeders are the ones doing things the RIGHT way in their breeding.

For me, it all comes down to each person has to follow their heart and do what they feel is best for their family and the dog based on their particular situation.