Well now i think im inclined to agree with you.
I have been defining it as a true chicken is the animal that came from the egg and reproduces the same animal in egg form.

But if you were to say instead that the final mutation that created the gentically distinct animal we call a chicken, would still be that animal regardless of how it was created.
Similar to if a chain of self replicating robots is traced back to the origonal unit, its still a self replicating robot even if the first was built by hands.