Mrs. GWN and I have had rescue's most all our lives but just recently we were introduced to pure bred pups. It all started with a male Boerboel that had the "wrong" color toe nails so he didn't sell. I was gifted him after we lost our dog & now we have two new ones, another Boerboel and a Beagle.
I really can't tell the difference in their affection or loyalty - as much as we want to believe dogs "know" they were rescued I'm not so sure.
Our current pack loves us unconditionally (as long as I fill those food bowls twice a day
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) and that's good enough for me.