What breeds? I have grown up having both too (we are animal lovers), my mom has 4 dogs now and she has rescued and bought purebred. Health issues vary. It can definitely depend on the treatment of the animals, breeding standards, what breed it is (my dog has some skin issues but this is typical of her breed), luck of the draw. I definitely think if someone wants to buy from a breeder or rescue a dog they should do their research first, but like I said in my post, I won't push on others what they should do! Having a pet you love and take care of is awesome, however you got it.